Lost Frogs of Panama

After the trips

2010-04-05T07:23:00.000-07:00

As we analyzed the data following the trip, we found that the tadpoles were 95% gone. Given what had happened at other sites where the disease had already hit, it was clear the few remaining frogs would be mostly lost. Eventually, when they came down from the trees and came in contact with the infected water or other infected organisms they would succumb to the disease. The algae looked more abundant but in science, impressions are not good enough. We analyzed our samples and this confirmed our impression, the algae had increased by a couple hundred percents. My computer models of the metabolism (essentially the breathing rate) of the stream showed this had probably altered as well.

We received word from Heidi and Edgardo that there was going to be a dam built upstream of our field site on Rio Maria. This alteration in flow would really make an enormous change in the stream with vast disruption of flow and very likely huge amounts of sediment entering the stream channel from construction. The developer who promised two years before that the valley would not be developed did not stand by this statement. Rio Maria would never be the same, and Amanda’s next visit confirmed the dam had been installed and the damage to our study reach was extensive.

Matt, Scott and Karen keep giving talks on the disappearance of the frogs to scientific and general public crowds. Many don’t know about what has happened there, in spite of the fact that we are losing so many species.

Heidi and Edgardo continue their unending work at the El Valle Amphibian Rescue Center. They have added at least 7 new species to their collection since I was down there, and the public exhibits are now open. They have hosted several international film crews interested in the frog extinction issue. The initial flood of press that occurred immediately after word came out of the disease reaching El Valle is over, but there continues to be interest in the topic. Some money is coming in, but more is always needed. There is no end to the need for work and resources required to care for and propagate the frogs that lived in the wild around El Valle. People who want to contribute to their work can do so through the Houston Zoo’s website.

Matt and I continued on our other projects. One of our aims in the US is to conserve and manage prairie streams, and there is lots of work to do on this, and little known about these streams. Issues such as expansion of trees and shrubs into grasslands, grazing, and water pollution from agriculture all are threatening one of the most endangered types of streams in North America, and the more we can find out about them the better. Emma and Bob keep working on the Grand Canyon and how to keep the ecosystem natural in spite of the Glen Canyon dam and other upstream impoundments altering the discharge. Cathy keeps working on other tropical sites including the island of Trinidad where she works with a group studying how environment interacts with evolution of the unique guppy species found there. Alex has his focus on tundra streams in Alaska and Iceland and ultimately the influence of global warming on those streams. Life goes on and there are other battles to fight. Still, losing the frogs at El Valle took part of me away that will never be returned.

In spite of the loss of the frogs, I want to return to El Valle. The area is beautiful and the people are fantastic. The loss of the frogs and then the quality of Rio Maria has left me as determined as ever to help document what people are doing to the environment around them, and how we can mitigate the negative effects we have. It also has helped me appreciate what we have in the natural world, and taught me to appreciate it today, because it may be lost tomorrow.
I still don’t know how to react to the lost frogs of Panama. It is a sad topic, and it keeps going around in my mind. It is like losing a loved one; you never forget but the time might dull the pain.

This cannot be a story with a happy ending. It is the way the world is going. Humans are spreading out and taking more per person, and most of the species on earth are hurting as a result. I hope my childrens’ children have the possibility of seeing a place like Rio Maria or other biologically rich areas in the tropics, on coral reefs, or near their own homes. Protection will only happen if people today want it to happen. As a biologist, my job now is to let others know about what is being lost, and document what is happening as it is.

The last days in El Valle

2010-03-29T07:51:00.000-07:00

Before we left we all took a last look at the site. I am usually sad when I leave a research site, but was more affected this time. I had become attached to the stream. The frogs were gone and this was a huge blow. The impending construction led me to believe that much of what made this stream special would be gone if I ever made it back again. We drove up the bumpy dirt road each lost in our own thoughts.

When we reached the point where the pavement began I got out to turn the locks off on the hubs from four wheel drive. I noticed the front tire was low so we started back to town to get it filled up. Just before we made it to the gas station where it could be repaired the tire went completely flat. When they realized our tire was flat, a couple of men immediately ran over to help. We all knew how to do it, but they were so enthusiastic that we allowed them to do most of the work. In the US people are generally a bit less willing to help a stranger. It is possible that they did so for hopes of a tip, but they did not seem to expect anything for their attention.

We finally got back to the hotel, and by 7:00 that evening had processed most of the samples and made some progress on analyzing the data collected from the electronic probes we had in the field over the last week. We cleaned out the back of the trucks and found out that Cathy had left several pairs of dirty socks. This was certainly expected.
Our first look at the data suggested that the reason for the dense algal growths in the stream really was the lack of frogs. The discharge of the stream and other basic properties were almost identical to what we had measured two years ago; temperature was within a half degree Celsius. The tropics are remarkably constant relative to many temperate habitats.

Piet had collected some samples for Emma that required centrifugation. We took some time off for dinner, and after we got back Piet worked on samples until about midnight. Heidi brought over a guitar for Alex and I played harmonica with him for awhile. We turned in relatively early because the next day we would leave for Panama City and we had a lot to get done before we could leave. Amanda would stay behind and continue sampling at the experiment site. I lay in bed contemplating the loss of the frogs and the construction on the site.

I was concerned about Amanda’s financial condition and left her some money. She had some problem with money being transferred into an account in the states, and had very little to live on for her next month in Panama. This was paying it forward in a way.

When I was a student traveling in Costa Rica, Dan Janzen was staying in the hotel we were using. Janzen is probably the best known living tropical ecologist in the world. He has dedicated his life to studying and conserving the tropics. He has since been elected a member of the US National Academy of Sciences and received the half million dollar McArthur Fellowship (the “Genius” award). He is one of my scientific heroes.

The hero bit was cemented given his response to an overheard phone conversation with my parents about wiring money to Guatemala. I was going there next by bus, and they had not received an earlier request from me to wire money to Costa Rica. When I got off the phone he asked me how much money I had. I told him I had $50, and he immediately gave me $100 more. He knew it possible to be refused entry into many Central American countries if you were not carrying enough money and I could be stranded at any of the four border crossings between Costa Rica and Guatemala. That was a good bit of money to give a stranger in 1977. I had to bother him for an address to send the money to repay him, and have been an admirer ever since. My admiration has only increased due to his untiring work to preserve tropical biodiversity, including helping establish the National parks of Costa Rica, and habitat restoration in that country.

Packing the next day took a long time. We not only had our own gear, but many boxes of scientific equipment that needed to be organized and packed and moved into our one remaining room. I took a brief walk up the stream that flows by the hotel and noticed a large raiding party of army ants on the trail. Thousands were spread out in one area, and columns of them were racing along a cleared trail across the forest floor. Many were carrying insect parts and others were carrying eggs and larvae.

I made the mistake of mentioning this to Alex when I returned and he grabbed his camera and ran out of the room. He returned later with a grin and a number of bites from the soldier army ants. Packing took all morning and took longer without Alex. We finally went to grab lunch with Heidi and Edgardo. After lunch, we threw our gear in the back of the truck and headed out of town. The remainder of the trip was unremarkable. This was good because riots were still occurring in Panama City. The only evidence we saw of them was a large line of army personnel with machine guns standing guard around a building as we drove to the airport at 6:00 am. Evidently the rioters kept more civilized hours.On the plane I reflected on how out of kilter my second trip to Panama seemed relative to my first. Foremost, was the disappearance of the frogs. Second, was the development entering the valley of Rio Maria. Finally, all the little things, getting sick, the stolen computer, the flat tire, the malfunctioning gear, Matt being worried about his animals, and concern over the riots in Panama City, that had happened this time but not the last .

The end of the experiment

2010-03-22T08:33:00.001-07:00

We returned to the hotel and analyzed our samples for nitrogen. We were done around 4:00 in the afternoon and decided to drive down to the beach. Alex opted to stay behind. He needed to teach a lecture to his class the morning after he got home. His notes for it were on the disappeared laptop. He borrowed one of our computers, planted himself with two pillows propped behind his back on his bed and got to work re-writing his lecture.

Not 15 minutes after we left, he heard a sound at the window. One of the maintenance men from the hotel was climbing up a stepladder to the window. Looking quite startled to see Alex in his room, he continued climbing and did something right above the window.

He left rather quickly and a short time later another hotel worker came and took the ladder. Alex went out to look at what the maintenance man was doing but saw nothing other than a concrete sill and the top of the window. Nothing looked changed or worked on; there was essentially nothing to work on there.
It all seemed very suspicious given that Alex’s laptop had disappeared from two rooms down, and the thief hand entered through the same window. We decided Edgardo was probably correct about who had taken the computer earlier, but had no way to do anything about it.

The next day was our last field day and we needed to collect samples of all the organisms in the stream so that we could determine where the nitrogen tracer had ended up. We collected algae from rocks, rotting leaves (filled with fungi and bacteria), and fine sediments both at the water surface and from the stream bottom. These are the primary food sources for the few remaining tadpoles, and many of the invertebrate larvae, freshwater crabs and few freshwater shrimp in the stream.

The other animals still in the stream are predators, such as the large (half inch long) vicious dragonfly larvae with extendable jaws that flip out and jab prey, and the dark brown hellgrammites as long a pinky finger with massive pinching jaws. A little caution is necessary with the hellgrammites because their jaws can draw blood. Amanda collected the animals because she had the collection permits from the Panamanian government, such permits are not necessary for leaves, sediment, and algae.

We pulled all our electronic probes out of the stream and attempted to download the data. I went to get the light meters from a clearing on the hill and walked down the new road carved over the last few days into the hillside above our research site. It went to an area along the hill about half way up our experimental reach.

The new road had broad areas of dirt that had been exposed. At the top of the cut, it was easy to see that the jungle soil has a thin black layer that sits on a very poor mineral soil beneath. In the US, this type of construction would require that materials be placed over the open sediments to stop erosion from allowing the sediments to pollute the nearby streams. No such requirements are in place in Panama, or if they were, they were not being enforced. Luckily, sediments from the construction had a hundreds of feet to go through the forest and densely vegetated side channels before reaching our stream. The rapid regrowth might cover the open sediments before the rainy season came and erosion began in earnest.

The sediments would not influence our results from this week. However, once all the houses were built in the marked lots, it looked very likely to me that the portion of Rio Maria we were studying would become severely degraded. This was sad, but being a researcher, thoughts of coming back to document the effects also occurred to me. Just recently ecologists have started studying urban and suburban streams in the US, but little work has been done elsewhere in the world. With our extensive background data, we would be able to detect any changes that occurred in the stream. This seems to be the way than many scientists deal with bad things, they study them.

Upon my return to the stream with the light meters, I learned that one of the instruments had malfunctioned, but we had a duplicate, so this was not a problem. The pump that had been used to release the tracer was turned off. As we carried the last of the sampling gear and electronics it started pouring rain. The group joke was “Dry season? This is a heck of a way to run a rain forest”. Not a great joke, but it had rained every day and this was an unusually wet dry season .

Truck swap and the cloud forest

2010-03-17T08:05:00.001-07:00

Later that evening we continued processing samples and preparing containers for the next day of sampling. Procedures for dealing with samples mostly consisted of filtering, but a lot of care was required not to cross-contaminate samples. Samples were dried if possible and frozen if not. Frozen samples were difficult to transport back to the US, but it could be done with a cooler and the maximum of 4 pounds of dry ice that was allowed to be checked in luggage. It makes sense not to allow more, the dry ice can release a large amount of carbon dioxide, and if this occurs in a confined area could possibly cause suffocation.

The next day the four early departures left for Panama City and the rest of us went to the field. After a typical day at Rio Maria, we finished our sampling and drove back. Just as we got to the hotel, Amanda’s phone began to ring. When she dug it out, we found out that Matt had taken the wrong truck to Panama City, and the people at the Smithsonian Research Institute were insisting that the correct truck be returned. This was frustrating because the trucks were the same make and the same age. They insisted on the one we had so Amanda and Alex had to drive to Panama City to exchange them. They drove down and back (4 hours) while Bob and I worked on the data we had collected. They finally retuned at 1:30 am. At least they got a good dinner at our favorite Peruvian seafood restaurant in the city while they were there.

The next morning as we traveled to the field site, I started to feel the pounding of the road. It was not as bad as during our previous trip because about half of the road had been paved since then. Still, the two steepest hills were rough clay roads with ruts, and we all mentioned how we were beginning to feel it. It is amazing that there are truck and bus drivers that take the lower half of this route all day every day.

The day was a short sampling and experiment day. We started experiments and then waited three hours to read the results. Alex had broken the edge off a termite nest attached to a tree and we watched them repair the damage as Alex narrated with infectious and perhaps slightly deranged entomological zeal.
When their nest is damaged, termite soldiers swarm out to protect it. This species of termite had soldiers with nozzle heads. The heads release a sticky excretion that clogs up any predator. After the initial disruption, the colony settled down and the workers started moving to the edge of the damage and placing bits of masticated wood or soil and then turning around and cementing them in with secretions from their abdomens. Within a day the edge of the nest was sealed off.

Termite nests are most commonly preyed upon by raiding ants. The first defense is a strong wall on the nest, the second the soldiers gumming up the ants with their adhesive. The social insects in the jungle are either constantly at war with others, or under the threat of pirate-like attackers that literally are out to eat and or enslave their prey.

While termites are a nuisance to homeowners because they eat wood, they are a vital part of tropical ecology. They break down dead wood and release locked up nutrients much more rapidly than would occur otherwise. Termites have specialized microbial communities in their guts that break down cellulose and make the carbon available to the termite. Fallen wood does not last very long on a jungle forest floor in large part because of termites and the fact that their activities increase rates of bacterial and fungal breakdown of wood in this warm moist habitat.

Interestingly, termites are one of the larger sources of methane in our atmosphere. The bacteria in their gut release the gas into the atmosphere. This is an important greenhouse gas that contributes to global warming. The first estimates of release rates were too high because they did not account for the presence of other bacteria in the walls of the mound that eat much of the released methane before it escapes into the atmosphere.

On our trip back from Rio Maria to El Valle that afternoon we stopped at the highest point in the road and hiked up a trail to an overlook. Hiking the trail was very strenuous; it was only a half mile, but it was very steep. We had all our most valuable equipment (computers and cameras) with us because of the lack of security at the hotel, and the inability to properly secure items in the trucks. The hike was made a bit more difficult with the packs we needed to carry. Impressively, the trail had many concrete steps. The concrete had to be packed in on the narrow trail. The last bit of the trail to the top was wooden stairs, and they were steep and slippery.

At the top of the trail was a true cloud forest with what appeared to be primary growth trees. Clouds poured over the high mountains and the ridge we were on. A continuous mist permeated the air. The forest was dripping wet and mosses grew on every surface that did not have higher plants on it. The trees were not extraordinarily tall, presumably because of the fierce winds that pummeled the ridge during the many tropical storms in the area. Each tree was covered with hundreds of species of epiphytic plants. Their sides were enveloped with vines, and their branches supported numerous bromeliads and orchids.

The flowers were sturdy and apparently pollinated by bees or hummingbirds. In colder areas, smaller pollinating insects cannot move well enough to fly. Bees can thermoregulate to some degree by moving their wings to increase their body temperature. Their relatively large bodies do not lose this heat as quickly as those of their smaller relatives. Hummingbirds, of course, are warm blooded. To some extent the large bees, and certainly the hummingbirds can fly up the steep hills from the warmer lower elevations in a matter of minutes.

The view from the top was spectacular, as clouds moved rapidly across the mountains and others opened temporarily nearby allowing us glimpses of pieces all around us. Immediately across the nearest valley, the large pinnacle of rock (the remains of the core of an old volcano) had a lake right at its base. Called a Marr lake, it had formed when a steam explosion underground made a perfectly round hole. Behind us, El Valle nestled in its 6 mile wide crater, was formed in a similar (albeit substantially more catastrophic and impressive) fashion. Thirty miles away, the ocean was visible and the steep gradient of moisture between it and us was apparent.

The cloud forest we were in gave way to a less stunted forest first, then eventually to a dry seasonal forest. Since this was the “dry” season, many trees on the lower slopes of the mountain had dropped their leaves and were now brown. They would grow new ones once the wet season started again. But for now, the transition from green, to brown, to the blue ocean was brilliant.

We could see the development encroaching on the entire watershed of El Valle. Tropical forest was being bulldozed to make half million dollar homes. The cul-de-sacs were evident from miles away. These cul-de-sacs looked just like those in any new subdivision in suburban US.

The stolen computer

2010-03-08T06:29:00.000-08:00

Other than the fact that the frogs were gone, the trip was going well. However, the first signs of something less than a smooth trip came up that night. I started getting sick with both a cold and a case of Montezuma’s revenge (or, as referred to in Panama, Noriega’s revenge). Matt got word from home that a large ice storm had taken the power out at his house.

His family was safe and they had a fireplace, but it was not enough to keep the over one hundred snakes, lizards, frogs, and tortoises warm. Matt had a large collection, and if the power was out for a sustained period of time many of these animals could be lost. Matt spent a lot of time on the phone with his wife planning how to protect the animals. The temperate ones would be ok if it did not freeze so they were moved into the basement. The tropical species could die if they even got cold, so they were moved as close to the fireplace as possible. Matt’s wife is a good sport, but she no doubt did not want to deal with being stuck at home in a massive ice storm with no power. Matt felt guilty and worried.

The next morning things got a bit better when Matt found out that power had been restored at home, and we once again went up to the stream to do research. We needed to collect our electronic sensor data. When Alex went to do that we found that the commands to start the electronics had been entered incorrectly and we had no data from the previous collection. Fortunately, we had several more days to collect data so we proceeded with experiments to find out how the invertebrate insect larvae, fish, and crabs would respond to the lack of tadpoles competing for the food that they also ate.

That evening we walked to a nice new restaurant nearby and had a fantastic dinner. While wandering home we got a bit lost. We were in a good mood when we got back to the hotel and planned to chat over drinks. Then Alex discovered that his laptop computer was not in his room, and suddenly things did not look so good. His first concern was not the value of the computer, but what data were on it that had not been backed up. Fortunately, all the data from Panama were backed up, and the rest of Alex’s possessions (particularly his passport) and our lab gear were still there.

Unfortunately, Alex had just returned from a winter sampling trip on the North Slope of Alaska near Prudhoe Bay, and all his photographs from that trip were lost. Photos from Rio Maria were also gone, but they could be re-taken.

The police were called and we ascertained that the thief had entered through a window. Edgardo suspected that someone from the hotel was responsible, but we were not so certain.

The only amusing moment of the night was when Matt went out and around to the window to see how easy it was to reach into where the laptop had been. He had his head and body in the window and was reaching down toward where the computer had been when the police, who had just arrived, walked into the room. Matt turned very red and the police eventually understood what was going on, but it looked a bit suspicious at first. We had returned at 10:00 and the police were there for 3 hours before they left.

The next morning we woke up and realized we needed to reassess our approach to security and decide if we wanted to stay in the hotel. We could not afford the time it would take to move, so decided to stay put. We fashioned bars to put in the windows and figured out hiding places for our valuables. Most valuables we either needed to take with us or leave somebody behind to guard the rooms. This was not too difficult that day because we had a number of samples that needed to be processed in our laboratory/ hotel rooms, so some of the group stayed. Alex went with Edgardo to the town an hour away where the police report needed to be filed with the detectives. We knew that this was a lost cause, but Edgardo wanted to document the string of problems that had occurred at the hotel.

The research project, at least, was only coming up against minor hitches and seemed to be going well. We returned from our field day and went to dinner as a group. While we were out we heard that police had shot a labor protester in Colon, the Panamanian city on the north (Caribbean) side of the Panama Canal. The riots from Colon had spread to Panama City. The police had arrested 500 people and Panama City was being shut down. Matt, Karen, Kathy and Emma needed to leave soon and we started feeling concerned about getting out smoothly and safely. El Valle was safe, but we needed to travel through Panama City to get home.

The Disease

2010-03-01T07:33:00.001-08:00

That evening we had several discussions about the disease and the decline and loss of frog species. This was fascinating to hear because Karen is a world expert on it and Heidi and Egardo are local experts on methods of culturing and modes of disease. Both have dedicated their professional lives to different aspects of the disease.

Not much is known about how the disease propagates and why it kills some species and not others. The thought is that the fungus is centered on the streams and when adult frogs come in contact with the stream or infected animals they contract the disease. Some tadpoles can withstand the disease, but others loose their mouthparts and become unable to feed. The mode of disease transmission explains why there were still some tadpoles in Rio Maria. Adult frogs can live for many years and do not necessarily breed every year. If a frog stays out of the stream and has no contact with infected individuals, it may live through the first wave of disease. Eventually, however, the frog mates or contacts another frog with the disease and contracts the disease.

The frog-to-frog transmission also makes sense with respect to the rate of spread of the disease. The disease spreads through the lowland tropics without killing most species. Apparently at the higher temperatures, the fungus is less deadly to amphibians found Central America. Models of the rate of the disease spread based on animal-to-anima contact are consistent with the observed rates of spread. The wave-like movement of the disease front is also consistent with an amphibian contact route. If the disease was spread by wind or carried around by birds or flowing water, the rate of spread and geographic pattern of disease spread would be very different.

Karen also mentioned recent research indicating that the cause of the spread of the disease is not well known. Recent results suggest that the African Clawed Frogs are not the source of the disease because genetic analysis indicates the strain of fungus originated in New England.

However, the disease was reported in samples of Clawed Frogs taken in Africa as early as 1938, the approximate time when international trade of the species began. The presence of the disease was determined in museum specimens. Nobody knew about this disease in the 1930’s when the sample was collected. However, modern techniques can isolate DNA from preserved samples, amplify it with the polymerase chain reaction method, and analyze the sample for genes that are only found in the chytrid fungus that causes the disease. This is the same procedure used to exonerate criminals in rape or murder cases that are many years old; the biological samples from the crime are analyzed for the DNA left in them. Biologists trying to reconstruct genetics of the past now analyze tiny bits of samples preserved in museums.

The difficulty with pinning down an exact source of the frog disease is that many species of frogs are moved around the world all the time, and other species can carry the disease as well. Indiscriminate movement of species can have very negative unforeseen consequences. The end result is the same regardless of exactly where the disease came from; the disease is in Central America and causing numerous extinctions. The moral for the future is that we should be very careful about moving biological materials around the globe.

Regardless of the exact original cause, the disease has spread around the world and is endangering species in many places. The disease was first recognized in Australia, where it has caused many frog deaths and spread to New Zealand and Tasmania. Only a few realized the problems the disease caused in the US because it spread in the mid 1900’s when people were unaware of the issues or and frog populations were not carefully documented. Now people are becoming aware of the disease in the US. For example, it is harming salamanders in the Southeastern part of the country.

With so many people and animals moving around, the spread of the disease is inexorable. In South America, separate infections were initiated in several distinct areas and now it has spread through much of the northern part of the continent.

The Amphibian Rescue Center

2010-02-22T07:35:00.000-08:00

That afternoon we visited the El Valle Amphibian Rescue Center that Edgardo and Heidi were running. The facility is located in El Níspero Zoo and Botanical Garden. This is a beautiful facility. The buildings are nothing special, but he grounds have fantastic gardens with a huge diversity of plants.

The zoo and garden are quite different from those found in the US. It was originally a private animal collection before the owner decided to open it to the public. The zoo breeds animals for sale to the public, including some very valuable fighting cocks. The animal rights politics are obviously different in Panama than in the United States, where no zoo would breed and sell fighting animals.

The botanical garden propagated and sold plants. There were rows of tropical ornamental vegetation. Many of these are common houseplants in temperate areas, but they were huge and showey growing outside here.

The zoo is also involved in a conservation effort trying to rehabilitate tapir populations in Panama. The tapir was extirpated by hunting in Panama, and now they were breeding animals to re-introduce into the wild. They have large outside exclosures where the tapirs are held. Tapirs are large (adults are 6-7 feet long) and look like giant pigs with a short elephant-like prehensile snout. They are related to horses and rhinoceroses, and all species are endangered. They were not very active when we were there, being a nocturnal animal.

The Rescue Center is at the back of the zoo in a new building that is being outfitted as a public display on one side and an area to grow frogs on the other. They had recently received a large donated shipment of aquaria for the displays. The aquaria were five or six feet wide, the same height, and a couple feet deep. The aquaria were shipped from the US and Edgardo had to spend some time negotiating with customs to get them without paying thousands of dollars in taxes. They were obviously worth a good amount of money, and the customs officials needed to be convinced they were for a non-profit organization.

The aquaria had been hauled to El Valle and now Edgardo was doing the back-breaking work of opening each large shipping container. The aquaria were somewhat delicate so they needed to be moved into the display area gently. While Edgardo had some help, it is obvious that he is not afraid of hard work and does not use the title of director of the center to avoid unpleasant jobs.

The display area is a large room within a room. The inner room, where the public visitors will be, has cutout walls that will hold the aquaria and the area outside the inner room forms a corridor in a ring around the building where the keepers can access the cages. The inner walls had newly finished murals of jungle life painted by a volunteer artist from the US. I am told that now it is finished, it is a very nice display. The paintings range from lowland to highland Panama and depict native species. The idea of the display is to educate visitors about not just the frogs, but also the habitats that they are found living in.
Next we went to the culture rooms. Before entering these rooms, we removed our shoes and put on bleached sandals. This was one of many steps necessary to keep the fungal disease out of the facility.

Two completed smaller rooms already had dozens of aquaria with frogs. These rooms were off of a central large room with twice as many aquaria as the two smaller rooms. This room was not yet finished, but was almost ready for use. Installing all the lighting, the misters to keep the humidity as high as it needs to be for the frogs to thrive, and access to all the aquaria required a huge amount of preperation.
The amount of work done to construct the facility in less than a year was amazing. It was very ambitious to make both the display area and the animal rearing facilities at the same time. This work was completed while also caring for frogs, going on collecting trips to areas the disease had not yet reached, and working with a large number of zoo personnel from the US and elsewhere.

The frog deaths in El Valle had led to international news exposure and Edgardo gave numerous interviews and had several news stories and documentaries written about him. He also took a tour of some zoos in the US to talk about the frog declines and the Panamanian projects. All of these various talks and interviews demanded time.
Initially, food was collected from the wild. This took a huge amount of time every day. Now, there were several insect cultures to feed the frogs. However, some food was still taken from the wild. The termites that some species of frogs eat were lured into buried fake logs, and then after the colony was established the larval termites removed and fed to the frogs. Learning how to grow the different types of food for the frogs took a good bit of time.

We viewed adults, young and tadpoles of the 15 target species that the center was working with. Heidi was obviously proud of each of these beautiful frogs and their ability to keep them alive. In spite of the year and a half of 15 hour work days she and Edgardo had put in, she was enthusiastic and energetic. She showed us every species of frog they had, and commented on what they ate, or how successful they had been in getting them to reproduce.
The most important objectives were to keep the frogs in the center free of disease and to figure out how to propagate the frogs. Some of the species have never been raised in the wild, and finding the appropriate conditions for the frogs to breed took a good amount of experimentation with temperature, moisture, food, and habitat variations.
There is a quarantine room, with the entrance from the outside, separated from all the others, where untreated frogs can be housed. The sick frogs, if they are not too far gone, are dosed with chemicals to cure the disease and held until it is fairly certain they do not carry it any more. This set up allows the frogs to be cleared of the disease before they enter the main rearing facility.

The clean rooms have several levels of protection. Entering water goes through filters with such a fine retention that the microscopic fungus cannot pass through them. Two local workers were working in gloves to work on aquaria. They were noting the condition of each frog, giving them the appropriate food, and cleaning the cage. Workers continuously spray disinfectant, and change gloves between working on each tank. The room that houses the higher elevation frogs is cooled, and every tank is regularly misted with an automatic system. The center has a large generator to deal with any power outages. Power outages are common in this part of the world, and a lack of power for any length of time could lead to untreated water entering the system and spreading disease, warming of the cool areas above the temperature tolerances of the frogs, and loss of the few remaining individuals of each of the species.

The center is successfully breeding frogs that would be completely gone otherwise. Their ultimate goal is to reintroduce the frogs into the wild. Frogs grown in zoos from many countries could not be used for this because they may transfer other exotic diseases to the Panamanian frogs. The short-term goal is to propagate enough animals to preserve the species and then to populate exhibits. The long-term goal is also to become established as a research center for veterinarians and scientists studying the frogs and the disease.

Ocelot tracks and colored beetles

2010-02-15T07:12:00.000-08:00

As always the jungle is fascinating, and every time you go, there are new things. Beetles as large as a thumbnail with bright yellow and black stripes were eating bright white shelf fungi that were growing on a log that had fallen over the stream. The color contrast was stark and beautiful. Nothing subtle about this bit of natural history. A river of leaf cutter ants used the same log with the beetles and fungi as a bridge to carry leaves back to their nest. Army ants swarmed across a nearby log.

At one point I thought I saw a frog jump away from my foot. When I finally located the moving animal, it turned out to be a lizard with its head shaped like a leaf. The lizard was so cryptically colored that it took me 5 minutes to point it out to Bob, even though we were a few feet away from it. We saw a number of other lizards and skinks during the day that apparently had not been killed by the disease.

That evening we were able to visit Heidi and Edgardo in their new house. The place was much better than the old lab they had been living in. They had a nice dog, and a yard now, and were within a short walk of the Rescue Center. It was fortunate they had found a good place to live, the real estate market was very tight in El Valle. The demand for second homes and tourist accommodations had led to first world prices in a developing country. Given that the rescue center paid very little, finding this house really made it possible to do the work they needed to do.

The next day we took a short trip to collect a few samples and check that the experiment was running properly, including changing the solution that we were dripping into the stream and measuring the pump rate. Everything was going smoothly. Once that was done we had some time to take a walk upstream. There were occasional tadpoles and I found the only adult frog of the day. It was no bigger than a dime that looked more like a moss than a frog. I only spotted it because it jumped when I stepped near it.
On our way back downstream we saw a track in the sand which we photographed. Electronics have made this a very small world. We sent an email of the picture to a world expert on mammal tracks, and he confirmed that it was an ocelot track. This was interesting news since we had seen no other evidence of large animals. The monkeys, peccaries, and other large animals that would have been in a pristine jungle in this area had been hunted out, but somehow this large cat was holding on.

The next day Alex found some scat, a ropelike pile of feces on a rock in the center of the stream. This is the habit that ocelots have when they excrete feces. We got back fairly early and Karen Lips and her student had arrived from other sites in Panama where they had been surveying for frogs and lizards the past few days.

This was the first time I had gotten to talk to Karen Lips. She is petite with short, dark stylish hair, a quick smile and large brown eyes. Going into the field with her, I was impressed that she was better dressed than most field ecologists and somehow managed to stay clean even though she was working her way through a muddy jungle. Her life revolves around study of frogs and she spends 3 months in the tropics most years. If you want to start Karen talking, frogs are the topic guaranteed to get her going. She doesn’t just talk about frogs, she is animated and strongly opinionated about any controversy in the world of amphibian science.

The frogs at El Valle were really gone.

2010-02-08T07:14:00.000-08:00

When we reached the stream, I hopped out. I walked to the streams bank and started scanning for tadpoles. The pool at the road crossing had a few small ones on the sand bar, but far fewer than our last trip. There were none of the large species that attached to the rocks in the faster moving parts of the streams.

Strikingly, bright green filamentous algae covered the bottom of the pool where very little had been two years before. My first guess was that the increased algae was related to the decreased grazing by tadpoles. Without the herbivorous species of tadpoles at high densities, particularly the large ones that attached to the rocks and moved across them eating the algae, the algae attached to the rocks was able to increase dramatically. This is exactly the effect that Karen had describe to Matt occurring at other sites where the frogs had disappeared that got Matt started thinking about the whole-system consequences of the frog die offs. The system, even at first glace, was obviously different from 2 years ago.

As I walked up the stream there were no adult frogs at all. This same trail had so many that their calls were constant and it was difficult not to step on them two years ago. I had been dreading this since leaving the site two years before. The sound of heavy machinery in the distance had replaced the calls of the frogs that previously had filled the air along the jungle trail. The group did not talk about it. Some our group had not been there before, so could not truly understand the changes. The rest of us just did not talk about it but went about our work.

We took some samples to the truck and Edgardo drove up to help. Heidi was back at the Rescue Center and had no time to help with the research. Heidi and Edgardo had a new vehicle from their work with the North American zoos. I gave Edgardo a hug and we looked each other in the eyes. I knew he understood what I was thinking. I mentioned how depressing the loss of the frogs was. His reply was “You have no idea”. Of course I had no idea. He had worked on these frogs for years. He had dedicated is life to them.

We took a few background samples and put in some monitoring equipment. Then we drove back to the hotel and started preparations for the big field day the next morning. I got into Amanda and Piet’s room and started cleaning up the lab area. I don’t really care how people keep their personal space, but dirty and cluttered lab space leads to disorganization and lost and contaminated samples. The room was so bad otherwise that Amanda started taking showers in Matt’s and my room. The one in her room was filthy.

Cathy Pringle had arrived seperately at the hotel while we were gone. She asked if the frogs were really gone. Piet had emailed earlier that some were left. We all wanted to believe that Rio Maria would not be hit as hard as the other sites. I had seen the stream, and it was obvious what had happened. I told her how sparse they were and she shook her head.

Alex briefly talked to me about the frogs being gone, he was obviously upset. Bob did not seem as upset, but he does not share feelings, so it was difficult to tell for sure. At the time he seemed more concerned about cocktail hour. Maybe it was displacement behavior. Matt and I were rooming together and talked before we went to sleep that night. He mentioned that when he had gone through this at a previous site, he had hoped in the back of his mind that Karen Lips’ predictions about when the disease would hit and how it would decimate the frog populations, would be wrong. But she had been right. We had gone through the same thing at Rio Maria. Intellectually I knew they were gone, but the reality was not easy to bear. This time Matt knew what to expect and was not as shocked. The drinks that evening had done nothing to lift my spirits, and the mood was somber as we fell asleep.

The next morning it took us a few hours to get our gear together and head up to the stream. We got there around 10:00 am and started to work. There were 9 of us and we worked until 6:00 pm. We only heard 3 frogs calling and saw one living frog. Heidi and Edgardo grabbed it and took it to try to culture it and treat it for the disease. It would be placed in the quarantine area of the Rescue Center.

It was a long and exhausting day, and the changes in the stream became obvious as we sampled. We were moving up and down the banks of the stream using the trail that had been cut by machete two years ago. Of course the jungle regrows rapidly, and a good amount of vegetation needed to be removed to make it possible to move up and down the trail with all the equipment we had. The observation of more algae was borne out as we took more quantitative samples. There were more fish, and more invertebrates that eat algae. Some of the invertebrate larvae that relied upon the activities of the tadpoles were gone. The diversity of the tropical forest was as startling as ever, with the exception of the frogs.

Back to El Valle

2010-02-01T07:27:00.001-08:00

The trip down to Panama was uneventful. Most of us met in the Atlanta airport to catch our flight. Matt and I sat in a bar in the airport and went through figures on the textbook we were writing. We also started planning the logistics of the next round of experiments. We continued the work on the plane in spite of Matt’s propensity to air sickness. We arrived in Panama City, again the blast of tropical air getting off the plane and a late night trip into the city center.

Piet and Amanda met us in the airport. Amanda Rugenski is a graduate student in Matt’s lab. She has a brown ponytail, a husky voice and an athletic bearing. I found out later that she is into outdoor recreation and enjoyed hard core skiing, rock climbing, back packing and mountain biking. Amanda is very smart, quick on the uptake, and turned out to be very good in the field. She told us a story about getting a guy to but dinner her the night before and then ditching him, and I decided that maybe she was not very cautious. Apparently her personal approach to life was exemplified by the extreme sports she was engaged in.

This trip, my luggage and everyone else’s made it. The drill was the same as the previous trip. Matt ran to the Smithsonian to check in and prepare chemicals and get vehicles. We drove out of the city and picked up supplies. We had a difficult time deciding which aged rums to buy to try. By the next afternoon we had made it up to El Valle, checked into our hotel rooms, and got our gear ready for our first quick trip to the stream. We needed to get a few samples collected and start some equipment running. Piet launched into questioning me about the experiment immediately.

The Hotel Campestre was in obvious disrepair. The large lobby and one wing of the rooms had been completely torn down and only partially rebuilt. It had been only two years but the grounds were less well kept and the jungle was creeping back in.

The building we had used for a lab and housing 2 years before was not available and Amanda and Piet had only one room/ lab to use. The room was a wreck with equipment and dirty clothes everywhere. They had not had any maid service so there was a peculiar smell in there. The large amount of water filtering had led to some spills. Apparently, neither was willing to clean if the other did not, and neither did. I initially felt bad for the hotel staff who would ultimately end up cleaning up the mess, but these feelings lessened as events unfolded.
The road to Rio Maria was quite a bit better than before. It was paved up to the first steepest hill. Some of the pavement was not great because it was covered with gravel and almost as slippery as a muddy road. The top of the road was as bad as ever, there had been a landslide across it and it was very muddy and rough.

As we went over the lip of the volcano and down into the Rio Maria valley the most striking thing was the new paved roads and fresh gashes through the forest to construct dirt roads. A housing development was being constructed across the valley very near the stream. As we approached the stream the road widened and had obviously been improved. A hundred feet of jungle had been bulldozed out on either side of the road. It looked like development on both sides of the Rio Maria was going to happen in spite of the fact that there were assurances that the watershed would be preserved only two years ago. Obviously the developer/ land owner was not telling Edguardo and Heidi the truth earlier.

frogs, bison, overkill, and extinction

2010-01-25T11:55:00.000-08:00

I left home and drove through the Flint Hills of Kansas on my way to the airport to catch my flight to Panama City. It was a frigid morning, and the tallgrass prairie was starkly beautiful. The sun was rising and the light gave a slight orange/pink hue the wind-burnished patches of snow clinging to the northern slopes of the rolling hills. The old big bluestem grass stalks were buffeted by the winds. This was the kind of morning that made me glad not to be living as the indigenous people did during this inhospitable time of year. This was the type of morning where the Native Americans, and later the European settlers that invaded the area, would have stayed inside till the sun took the bite off the bitter windy cold. The icy landscape was stark contrast to the tropical mountain rainforest that I was headed to.

As I drove through these prairie hills, my mind started worrying on the idea of extinction, ecological loss, and the modern world. Only a fiftieth of tallgrass prairie remains in the North America, much of it in the Flint Hills of Kansas and Oklahoma. As I drove to the east, and out of the Flint Hills, the land was taken over by croplands. In a few minutes I was witnessing the transition that altered the vast North American prairies when Europeans broke the sod in the 1800’s. Much of the Midwest’s productive cropland was once a sea of grass.
The Flint Hills only retain grassland by lucky accident. The shallow rocky soils make them better for raising cattle than cropland. The ranchers burn yearly to keep the trees at bay and the cattle simulate the herds of grazing bison that historically roamed the prairie. Where fire has been suppressed, the trees invade. Prairie is becoming more imperiled in the Flint Hills because of the human influence changing the natural fire frequency that occurred. This effect is particularly pronounced in areas with higher population densities where people have built their houses out in the country… an effect that we will see has parallels in Panama.

Bison (popularly referred to as buffalo) are a “keystone” species that shaped prairie ecology, and their loss from the prairies could be considered analogous to the loss of the frogs in the jungle streams. The researchers I work with in Kansas have found that bison are key in maintaining the very high diversity of plants found in tallgrass prairies. There are literally hundreds of species of plants in a healthy prairie. The bison stimulate this productivity by grazing the main grasses that would outcompete the forbs (leafy plants). They also leave fertilizer packets (dung and urine) that stimulate plants that require higher nitrogen conditions. Bison disturb areas with their hoof-prints, their wallows where they take dust baths, and the trails they cut through areas as the herd moves across the landscape. The tadpoles, in the streams, do analogous things. They graze selectively, they disturb some areas more than others, and they excrete and enrich areas with their fecal pellets.

As impressive as the accounts were of massive bison herds on the prairies, there were once much more impressive herds of large mammals that roamed the prairies. Humans were responsible for even move extensive alteration of the natural ecosystems of North America. Before the end of the last ice-age approximately 10,000 years ago, the plains and forests of North America once were home to an astounding diversity of large animals. When tribes of hunter-gatherers that ultimately became the Indians of North America crossed the land bridge and spread across North America, they found a land of plenty.
The diversity of North America rivaled that of the plains of Africa. Camels, horses, huge bison, ground sloths, saber-tooth cats, giant beavers, giant armadillos, mammoths and mastodons were here. These large animals had no evolutionary experience with humans, and within a few human generations they were hunted to extinction.

Similar extinctions of large animals occurred in Central and South America as people swept in from Siberia, through North America and to the south. The America’s are not unique. In Australia, New Zealand, Madagascar and many other smaller islands the archeological and fossil record is unequivocal. When humans arrive, the large animals disappear. Marsupials disappeared from Australia, giant flightless birds were slaughtered in New Zealand, giant birds and lemurs were hunted to extinction in Madagascar. People are consistent in their heavy-handed environmental presence. We are the most successful species because we shape each environment we enter to meet our own needs.

The ecological effects of the extinction of the large herbivorous mammals and their predators are not well understood, but they were probably significant. Some species of plants remain that have large fruits with seeds that are only dispersed successfully over any distance when they pass thought the guts of large animals. The animals ingest the large fruits and carry the seeds within them substantially away before depositing the seeds with a packet of fertilizer. But, animals large enough to pull down tree limbs and graze the crowns of trees no longer range across the landscape.

One difference between historic extinctions and the ongoing disappearance of the frogs of high-elevation Central American habitats is that we can study the ecosystem effects of the removal of an entire taxonomic group in Panama. Perhaps these studies will help us understand the unintended ways that humanity is influencing global ecology and aid in mitigating or minimizing future impacts. At least it could help document some of the negative consequences that could come about from extinctions or extirpations of species.

Getting the team back to Panama

2010-01-18T07:53:00.001-08:00

Now, I was starting to see the direct evidence of the die off as it came through, provided by my colleagues on the ground as the disease wave passed. Scott sent photos of dying frogs around to the group. Alex had videos of dying frogs. The frogs look duller skinned and are lethargic. Their skin is sloughing off of their bodies. The frogs that are not quite dead are not able to right themselves when turned on their backs.

During the die off, the Scott and the other researchers that were there collected as many dead frogs as they could find. He sent a picture of gallon pickle jars full of preserved dead frogs. The frogs in the jars will be identified, but not all species are collected before they decompose.

The species apparently contract the disease when they contact other sick frogs or come in contact with the stream. Some of the species in the trees might avoid contact for some time, but eventually, they will become infected. Thus, the die off is fairly concentrated, but some obscure species might hold on for a few weeks or months after the main epidemic sweeps through the jungle. Some of the species of frogs will probably never be known to science and will be lost in nature before they are described. Watching these videos and seeing these pictures made me even more apprehensive about returning to El Valle.

This group was to be slightly different from the last. Matt, Bob, Alex, Piet, and Cathy all were coming. In addition Karen Lips was going to be able to participate (if her luggage made it this time). Emma Rosi-Marshall from Loyola University is a professor who had been working with Bob on the effects of flooding and other influences of the dams in Grand Canyon. She had also been involved with the nitrogen tracer work our groups were doing in the U.S. She was interested in advanced techniques to separate the nitrogen label from the sediments.
Emma’s recent project with Matt on the effects of genetically engineered corn on stream invertebrates had generated considerable interest in the press. The paper she wrote for the Proceedings of the National Academy of Sciences with her colleagues documented how the toxin engineered in corn to kill the corn borer can enter agricultural streams where it could harm caddis fly larvae. Caddis larvae are important members of the stream community. The agribusiness community was extremely unhappy with her results, and she was attacked for them.

The tactic is familiar. Rachael Carson wrote the famous book, Silent Spring, that brought to light the problems with pesticide use. She was attached personally after critics could not rebut her scientific reporting. Tommy Edmondson, a professor at University of Washington, documented the decline of Lake Washington from sewage pollution generated by cities in the Seattle area. He carefully presented the scientific facts and left the politics out of his public statements. His critics could not assail the science, so resorted to attacks on his character. Emma had experienced a similar backlash.

Emma had strong expertise on stream food webs, and was a welcome addition to the project. Emma is a very boisterous and enthusiastic woman who loves to talk and argue science. She is an original thinker, and driven to do the best research that can be done. She is a tireless worker who is difficult to keep up with. I can see how she complements Bob, because he is the typical absent minded academic, and Emma is organized and gets down to business. Now we had the benefit of this dynamic duo.

Matt’s new graduate student Amanda, was also participating; she and Piet were already down in Panama working and she would stay and do the long term work after the rest of us returned to the US. As I would find out, Amanda was quite the character and had fantastic experience doing field work in streams.

A fantastic array of frogs

2010-01-11T07:47:00.000-08:00

What is it about frogs and popular culture? They seem to be a very fashionable small animal. Unlike insects or snakes, almost everybody likes frogs. It could be that there is not a natural aversion toward frogs because they will generally not bother you if you don’t bother them. Human’s evolutionary history does not include natural selection for avoidance of frogs like it does for avoidance of snakes. A frog jumping underfoot seen out of the corner of the eye catches attention. A snake slithering through the grass underfoot caught with the corner of the eye causes me to jump. Some princesses are even willing to kiss frogs (not a snake or a rat, but a frog, yes).

Some species of frogs have extremely potent toxin in their skins (the legendary poison dart frogs), but it is only dangerous if you eat or touch them. So, while we have a long evolutionary history of avoiding more aggressive toxic snakes and spiders, there is no similar danger from frogs through human history. Frogs have big eyes, and seem mostly un-threatening. Better yet, there are fantastically colored and shaped frogs that are fascinating to anybody who appreciates the natural world. Frog enthusiasts may not be as common as bird lovers, but there are plenty of them out there.

This attraction to frogs makes it all the more ironic that they are disappearing from under our very noses. If all the ticks and chiggers were disappearing, I would have difficulty working up as much emotion over it.

I asked Scott Connelly to send me pictures of frogs from the El Valle forests, and those that were dying from the disease in Panama. I had not seen many of these frogs when I was in Panama before because some are quite rare or active in other seasons. Still, I was curious about what was being lost. Scott is also deeply affected by the extinctions. He takes any chance he can to give public lectures using his extensive collection of photographs. He is surprised by how few people know about these frog extinctions, including other biologists. My experience parallels his on this score.

What Scott finds most amazing about these frogs is the astonishing diversity of form and function. For example reproductive strategies vary widely among species. Some frogs simply lay their eggs and leave, others care for the young. Male poison dart frogs of some species keep the eggs they fertilize on leaves wet by bringing water from nearby pools or tree holes. When the eggs hatch these males then transport the tadpoles on their backs to a suitable small pool and release them there to mature. Some frog species live in trees, others only on the ground. They all have different diets or other variations in their way of life.

Bufo coniferous is the green climbing toad found in El Valle. The adult looks like a typical warty (but attractive) greenish toad, but as a juvenile, it has brilliant red dots on its “warts”. Another member of the same genus, Bufo haematiticus is the blackbelly toad. This toad is light tan or grey on top and dark brown on bottom, with an attractive mottling of dark and light brown on the inside of its legs. It is thought to be abundant and not in much threat of extinction, but the chytrid was recently found to infect this species in high altitude areas.

Then there is Cochranella euknemos, the San Jose chochran frog. It is a pleasing, small, light green frog with all black eyes and a body covered with tiny neon yellow dots. This frog lives near streams in the vegetation and its populations are declining according to the Global Amphibian Assessment.

And there are more- Eleutherodactylus musous is a small, green, splotched frog that has protrusions of green and brown all over its body, and looks more like a clump of moss than a frog. Up to now this adaptation has aided the species survival because the camouflage helps it escape predation. This adaptation will do it no good against the chytrid. This frog only lives in the mountains of Panama and will probably go extinct from the disease. One cousin of this frog, Eleutherodactylus bufoniformis, the rusty robber frog, is an inch long round bodied animal that lies very flat to the ground. It has a splotchy skin that makes it look like a rock in the bottom of the stream or in the forest where it sits completely camouflaged.

There are even more colorful frogs. Rana warszewitchii, the brilliant forest frog, lives close to streams in forested areas and its tadpoles develop in the streams. It has a short trilled soft call. This forest frog is slender and brown with bright green splotches on its back, a yellow stripe in its groin and two bright yellow spots on the backs of its upper hind legs. One side of the bottom of each back leg is brown with black spots and the other side is pinkish red. It truly is a brilliant forest frog.

The coronated tree frog, Anotheca spinosa has striking strips of silver and pearl on its sides. It looks like a cross between a grey zebra and a triceratops dinosaur. It is three or four inches long, with bone spines on its neck; supposedly these spines are used to fight other male frogs to defend breeding holes high in the trees. After breeding, the female continues to return to the hole and lay additional eggs. The earlier batch of larvae consumes the eggs that the female lays. Presumably the purpose of the later eggs is to feed the earlier tadpoles.

Hemiphractus fasciatus is a 3 inch, buff, tan-colored, horned tree frog, with a flat five-pointed head. It has irregular splotchy bumps over its body. This frog looks more like a leaf than an animal. Initially scientists could not keep it alive in culture until they figured out it only eats other frogs. The habit of eating other frogs explains why it is only found in areas with high densities of other frogs. This frog does not need standing water to breed, although it is found in extremely humid forests, because the eggs are carried on the back of the female.

The jungle around Rio Maria is also the habitat of Dendrobates auratus, the green and black poison dart frog. These frogs have active males that sing a trilling note while perched on twigs or rocks above the ground. If multiple females are attracted they wrestle each other to mate with the male.

This is a personal favorite because we have some as family pets in aquaria at home and at work. We purchased frogs that were bred by a co-worker in the US, but unwittingly contributed to pet frog collection just by buying them. It is possible that much of the spread of the chytrid disease is caused by the pet trade in frogs. Furthermore, some species of frogs have been collected toward extinction for the pet and zoo trade. While this may be a way to preserve species, rarely are adequate records kept of collection location and breeding lines, so the genetics of the frogs is not preserved.

Dendrobates minutus, is the blue-bellied poison frog. This tiny frog is one of the few poison dart frogs that is not collected for the pet trade. It is a beautiful frog with alternating yellow and black stripes along its entire body. It has bright blue spots on its lower belly.

The above are only a few of the more than hundred species of frogs that could be found at El Valle. The main remaining species of frogs from this area now are in quarantined aquaria or have populations that also occur in lower, warmer elevation areas where the disease apparently is not fatal.

Lessons from extinctions

2010-01-06T08:39:00.000-08:00

Frog extinctions from the chytrid fungus are particularly troublesome because there is literally nothing that be done to stop them. Helplessness is a bad feeling, particularly for a scientist. Generally, a scientist thinks that we can control much of our world through knowledge. Species out of the wild can be propagated. If there is no way for them to survive in the wild, then they are doomed to be caged creatures. Somehow, animals in zoos do not seem the same to me.

I have mixed feelings about captive animals. A recent visit I made to an aquarium with extensive coral reef fish exhibits illustrates the paradox. I was thinking how much more I enjoyed seeing fish in the wild by scuba diving or snorkeling. Then it occurred to me that the resources used for me to travel to a coral reef were tremendous, and that the environmental damage would be immense if each of the visitors to the aquarium traveled to see all these fishes in their native habitat. The educational value of having these fish available for public viewing is high. Still, an animal or plant that only exists in zoos or botanical gardens seems more like a collector’s item than anything relevant to the natural world. For many of the frog species that are threatened by the chytrid disease, life in captivity is the only way the species will avoid complete extinction.

The El Valle Amphibian Rescue Center is attempting to save 1000 animals from 40 species. They are concentrating on 15 priority species now, and building capacity to save more. The center started in the same hotel (Campsetre) where we stayed. Heidi and Edguardo felt they had to do something, and rented rooms to set up aquaria in them. They collected frogs from areas where the disease had not invaded. They experimented with ways to kept the caged frogs from getting the disease, including washing with Clorox solutions, and heavy use of disinfectants of any materials that entered the area from outsize.

Since then, the El Nispero Zoo at El Valle de Antón and a number of US zoos (notably the Houston zoo and the Atlanta zoo) and conservation agencies have supported building a center to house the animals. The Houston Zoo manages contributions to frog conservation efforts.

In captivity, each frog must be kept quarantined from any materials that might bring the disease into their cages and as far as is known can never be released into the wild. To make the job even more difficult, it is not possible to maintain just a few frogs of each species because a minimum amount of genetic diversity is necessary to save a species. So, many individuals of each species must be housed. Furthermore, little is known about the mating and food requirements for many of the species, so research into these details is required.

Edgardo and Heidi were the first local collaborators (they became closer collaborators when they got married) on the conservation project, and now several zoos have pitched in to consult and provide financial support. Many hours of work a day at the Rescue Center are required to keep the frogs healthy including collecting the insects that each species needs to survive. Before the Rescue Center gained the ability to culture them in the lab, these insects had to be collected from the wild.

The golden frogs like termites, and many of the other frogs like cicadas, crickets, or other insects. The very small frogs need fruit flies or other tiny insects. A huge amount of work goes into cleaning cages, treating sick frogs, quarantining frogs that have been collected, keeping track of where each frog came from and recording breeding activity. This last is important to avoid inbreeding on one hand and to avoid breeding what might be distinct sub-species from different areas on the other.

Videos were coming out on the frog extinctions and the rescue center. I saw interviews of Edgardo, and pictures of the facilities and Heidi and Edgardo collecting insects to feed the frogs. Soon I would be able to visit and see for myself.

What are the lessons from the Panamanian frog extinctions? One is that diseases can wipe out species before people can find a cure. We are part of the natural world and are not exempt from the generalization. A disease could arise that kills much or all of humanity. With rapid air travel, pandemic’s are more likely. With more contact with wild animals, the probability increases that an animal disease will jump to humans. When people live in close contact with livestock (particularly pigs and waterfowl) development of diseases is particularly likely. It is not impossible that one of these diseases will be lethal enough to sweep through humanity causing mass mortality. If it can happen to frogs, it might happen to us.

Another lesson from the frog extinctions is that we need to preserve the species we can because we will lose many anyway from the unintended consequences of human activity. As already stated, humans are causing massive extinctions. If some of those can be avoided, the unintended extinctions we cause will have less of an overall impact on the planet’s diversity.

A third lesson is that we should not introduce species to other habitats (such as the African Clawed Frog) because there is always the potential for unintended harm. Species introductions have caused damage to numerous species and are in important factor in endangerment of many species. The chitryd and the frogs may be the most extreme example of a single introduction leading to extinction of 10’s to 100’s of species, but the lesson is an important one. These lessons still seem to me to be small comfort in the face of the loss of hundreds of frog species from our planet.

Extinction

2009-12-29T10:44:00.000-08:00

Dealing with extinction is difficult. All this was written because of my despair over the extinction of the frogs at El Valle, yet most of the writing dances around the actual issue. As the second trip approached, my dread at seeing Rio Maria without frogs increased. As a scientist the response is often to study the problem. Take for example cancer researchers that start a career because someone close to them is affected. Describing the science is like working harder to avoid thinking about the death of a loved one, it is ducking the fact that the frogs will never been seen in nature by people again.

The harsh reality, to me, is that most people do not care much about extinction of other species. In my introduction to biology course I ask a class of 80 students about this issue. I describe a local species that is going extinct, a small fish that is spiny and non-descript (the Topeka Shiner). I ask the class to raise their hand if they think the fish should be saved. Most of the class puts their hand up. Then I tell them to leave their hand up if saving the fish would be worth it if it required some personal expense to them. Over half the people in the class put their hand down.

A man has a business that removes gravel from some of the streams where Topeka Shiners still remain. He argues, in public hearings, that he is strongly against listing the species as endangered. He thinks that his right to make a living one particular way is greater than the right of that species to exist. He asks the crowded room, “what is more important, people or fish?” Many in the room nod in agreement with his arguments.

How willing are people to actually pay to save species? Is the life of a single person more important than the existence of an entire species? Is there a monetary value to a species? In a recent paper I wrote with my students we attempted to answer this question. The US requires recovery plans to be filed when species are listed as endangered. The average recovery cost was $732,000 per year. Some species cost much more to replace. Tens of millions of dollars have been spent on recovery of the black footed ferret. Total costs of recovery for the California Condor are in excess of $35 million over the last half century. Clearly some species are thought to be very valuable. However, putting a monetary value on species is dangerous. This sets up a situation where somebody could simply pay to be allowed to do an activity that threatens or causes extinction of a species.

Evolution is slow and mutation is random so that once a species has gone extinct, there is essentially zero probability it will ever return. The potential exception to this in the future is the technology for sequencing and synthesizing DNA is growing so rapidly that we might be able to completely recreate a species if the sequence of its entire genome is known. Scientists have already done this for bacteria. It is possible because bacteria have very simple genomes. It is not completely impossible that a complete genome could be synthesized and inserted into an egg of a similar species, allowing for recreation of an entire species. That is not possible for most species now, and probably for decades it will not be possible. For now, extinction is forever.

Current rates of extinction are thousands of times greater than rates of evolution of new species. It has taken 3.5 billion years for life to reach its current level of complexity. Over half the existing species are predicted to be gone in most of our lifetimes. Extinction is one of the major global environmental trends occurring during our lifetimes. We are living in unusual times where one species, us, can influence the entire planet. For the majority of species, we are a disaster. The reasons for this global trend and others are described more fully in my book, “Humanity’s Footprint”.

The fate of most species is to go extinct. As a scientist, I know that 99% of all species that ever existed on earth do not exist now. That fact does not make me feel better about humans destroying over half of all species on earth now.

In Douglas Adams’s science fiction novel “Hitchhiker’s Guide to the Galaxy” the planet Earth is destroyed to make way for an intergalactic bypass. The lead character escapes right before the destruction. He laments the loss of his entire planet but nobody from other planets seems to care much. The lack of interest by most people in extinction is similar; people who care about the plants and animals of the earth and are educated as to what is actually happening to them have a difficult time conveying the urgency of saving species. So many issues are deemed more important by most people, that preserving species ends up very low on the list.

I have dedicated my entire scientific career to studying ecology because I have always been fascinated by the natural world. I am a tree hugger. It is deeply saddening, both intellectually and emotionally, to know these losses are occurring.

It is curious to think about why people grieve. When a close loved one is lost, the feeling is physical. It is such intense emotion that it sweeps all else away. Yet, we know that people are dying all the time around the world, of hunger, disease, violence, and it has almost no emotional effect on most people. I think grief has deep evolutionary roots and leads to people protecting those who are related to them. That is why grief is so physical.

Little evolutionary advantage has existed for our species to protecting other species from extinction, just as there has been little evolutionary advantage to protect people we do not know well. Grief over loss of other species is intellectually driven emotion. Still, it is grief.

Utilitarian arguments for conserving diversity are good ones; species are the glue that holds ecosystems together. The next cure for cancer or some other disease may be found in an exotic organism or in the mold that grows in the dirt under your feet. Still, someday we could cure cancer some other way or find replacement species to keep ecosystems working in ways that provide benefits to humans. The ability to engineer ecological systems to perform functions for humanity does not, in my mind, make the extinctions acceptable.

The nitty gritty of science between trips

2009-12-21T07:42:00.000-08:00

Now that Matt had secured funding for a second research trip, we had a lot of preparation to do. One of the most pressing issues was the need to analyze the results from the first experiment. This work required analysis of thousands of samples. Many hours of work to be done included the tedious processing, grinding and weighing of samples. Samples needed to be submitted for analysis and when the results were received, the data entered. Once the data were entered, we need to use the computer models I had created to calculate the results. Given the fact that I am not the world’s best modeler, the calculations were time consuming and required a good bit of data manipulation. The results of this complex modeling would tell us the flux rates of nitrogen through the ecosystem before the tadpoles were extinct.

We needed to finish this modeling and analysis in order to be able to conduct the second large experiment correctly. A romantic picture of field biologists who spend all their time tramping about exotic locales is not accurate for many of us. The reality is that we spend more hours behind computer screens than we do outdoors. The further along the career of an academic, the more time spent writing and administering. A horrible fate, being a department head or, God forbid, a dean, will suck the life out of a research career and eliminate research trips to the field for serious science.

Understanding how nitrogen moves through ecosystems provides one avenue to understanding the way the stream works to support the life that is found there, and how it influences the rivers and oceans downstream. Many scientists had originally considered streams as gutters that simply transport everything that enters them downstream. The research that I have been involved with disputes that view. The science demonstrates that it does matter what happens in the stream with respect to what moves downstream. This understanding has assumed great importance in the US because nitrogen transported out of the Mississippi River into the Gulf of Mexico is causing major environmental problems.

This nitrogen pollution that originates in runoff from cropland moves through the streams and fertilizes the waters of the Gulf. The fertilizer stimulates growth of the microscopic plants that live in the surface waters where there is light. These microscopic algae photosynthesize, grow, and eventually die and sink to deeper, darker waters. When they reach this area, the bacteria that live there decompose the sunken microscopic corpses, and in the process use up the oxygen that is dissolved in the water. Most animals absolutely require abundant dissolved oxygen to survive. Fishes can swim away from the low-oxygen water, but the invertebrates that serve as food to the fishes do not swim so well will die in the low oxygen waters. The pollution is thought to cause substantial economic damage.

Stream ecologists such as myself, Bob Hall and a group of others have determined that what happens in the small streams determines how much of the nitrogen makes it down into the Gulf of Mexico. We, therefore, need to account for how much nitrogen is held back in each stream. This is part of the reason that the methods we were using in Panama were developed.

The second reason is that the way the nitrogen is used in the system alters the ability of different animals to exist in the food webs found in the streams. Thus, nitrogen allows us to characterize properties of the stream relevant to conservation of stream organisms. This conservation has the goal of maintaining the biotic integrity of the stream. Again, the methods developed in general would be useful in the specific case of the Panama streams.

I wrote a computer model to analyze the data. Matt and Bob checked it, and Piet started running it on the data we had. He had lots of questions about the model, and some of them were related to errors he found. After hours of re-programming and discussions with Piet and Matt about how to use the model, Piet was finally able to get some results. A true picture of the importance of the tadpoles in the stream began emerging. Piet’s work with the modeling confirmed that the tadpoles were central to how the ecosystem of Rio Maria functioned. The open question was what would happen once the frogs were gone.

Now Matt had funding and the group’s preparations needed to begin for our next trip to El Valle and Rio Maria. Matt made the arrangements to fly, ordered materials, and Edgardo started working on local arrangements. Matt needed to find some new students to replace the ones who had graduated. The ball was rolling toward the next trip.

Hustling for funds to get back to Panama

2009-12-15T07:13:00.000-08:00

The frog extinctions were starting to generate professional and public interest. Matt published results from his Panama studies done on the trips before ours in a very high profile, non-technical, ecological journal (the publicity magazine for the Ecological Society of America) and other more specialized papers from the group were coming out in the peer reviewed literature. Meanwhile Karen and Matt were receiving numerous invitations to speak at universities across the country where they would tell the story of the disappearing frogs of Panama and how the effects of these extinctions were reverberating through the ecosystems.

The research group also continued to make presentations at scientific meetings. Such meetings are great places to share scientific ideas and results with hundreds of others who are working on related issues. They provide the one time where scientific specialists are not the oddballs; nerd talk is the norm.

Matt and I attend a meeting of stream scientists every year and room together. Rooming with me may not be the most pleasant experience, but it is one way we could both use our grant money more efficiently. The day starts at 8:00 with scientific presentations till 5:00. Dinner is followed by a boisterous mixer in the meeting hall with hundreds of people discussing and arguing science. As with any large group of talking people, the volume increases to a roar. This makes for a long day, and after this Matt and I would lie in our beds and talk about science, our colleagues, and the state of the world.

Often our conversations would turn to the frogs in Panama. We kept trying to think of ways to strengthen the research. As in all science, every experiment leads to more experiments. In addition, the impending extinction of the frogs was something to worry about, even if we could do nothing to stop it. One thing we learned early on from rooming together at meetings, earplugs are essential.

One of the gaps in our research after our trip to Panama, and an issue Matt and the rest of us worried about for the next proposal, was measuring how much nitrogen is excreted by tadpoles. The tadpoles could be what we refer to as “ecosystem engineers”. Ecosystem engineers are organisms that have a disproportionately large effect on the environment and this effect cascades to the other species. Beavers that fill valleys with their dams, hippopotami grazing in fields and bringing nutrients they excrete back to the water, alligators digging water holes in the Everglades that last through the dry season, and bison eating dead grass and recycling the nutrients locked up in the grass available for the new growth of grass, are all examples of ecosystem engineers.

The tadpoles at El Valle were abundant and active enough that they could be major nutrient contributors to their streams. We were concerned with what happens when these potential ecosystem engineers in streams are lost. Some species of the tadpoles break down the organic material that falls into the stream in the form of leaves, and others clean the algae off the rocks. An interesting feedback is that the leaves become better to eat and the algae grow better when supplied with nitrogen. The tadpoles excrete nitrogen, and it actually stimulates production of their food. This excretion may also stimulate the microbes that serve as the food source for many of the tadpoles, insect larvae, shrimps, and fish in the stream. There were so many tadpoles in the streams that their effect had to be large, but how large was what we wanted to know.

Nitrogen excretion measurements were made while we were in the field with live tadpoles collected directly from the stream. The animals were placed in test tubes and then removed and released back into the stream. The amount of ammonia (the form of nitrogen excreted by the tadpoles) left after the tadpoles were removed was used to estimate the rate of their excretion. We did quite a few of these experiments streamside on the first trip with the samples returned to our rooms in Hotel Campestre for late night analyses. Our initial experiments indicated the rates of excretion were very high over the first few minutes and then decreased over time.

Bob argued that the tadpoles quit eating when they were placed in the experimental tubes and their excretion rates were slowing after a few minutes because of that. Alex and I thought that maybe stress was causing them to excrete more at the beginning of the experiment. Matt, being the diplomatic group leader, and a fine scientist to boot, suggested experiments were needed to settle the argument. This is the scientific processes. Our speculations formed hypotheses and now we needed the experiments to test them.

These discussions led Matt and Alex to run a series of experiments on tadpoles from the Midwestern US that are taxonomically-related to the tadpoles dominant at Rio Maria. These experiments proved that the higher excretion rates at the beginning were from the stress of being handled and put into a tube. Excretion rates from later in the experiment were more applicable to what the tadpoles were doing in the stream. Matt and Alex proved that handling tadpoles and putting them in large test tubes literally scared the piss out of them. These results were written up and submitted for publication in the scientific literature. They also strengthened the next proposal and would guide our experiments if we got funded to go back to Panama.

Another five months went by and the proposal was rejected again. This was extremely disheartening because once again, the reviews were fabulous. Matt called the program officers at the National Science Foundation to try to figure out how to get the proposal funded. The funding situation was getting dire because Piet’s and several graduate students’ salary depended upon continued funding.

We had agreed to fund the follow-up experiments in Panama out of our own pockets if need be, but we could not expect post-doctoral researchers or graduate students already living on poverty-level salaries to do the same. Luckily the program directors at the National Science Foundation agreed to some stop-gap funding to keep the project going and allow Matt time to apply for funding in the next round. One of the investigators on the grant actually paid Piet’s salary out of her personal funds for awhile. Scientists generally don’t enter the field of ecology to get rich, and many are quite generous with their time and resources, but this was exceptional. There is a long tradition of using personal funds for research; Charles Darwin had to pay his own way as naturalist on the Beagle.

Scientists through the years have had to scrape for external funding and we were no exception. Matt and the rest of us had to strategize on how to make the proposal sexy, compelling, and stress how imperative it was to fund the research immediately. We needed to write the proposal so well that the agency simply could not justify declining to fund it. Matt worked with the group on the best way to sell the research, and the proposal was submitted yet again.

The third time was a charm. I received an email from Matt telling me to plan to travel to Panama the following February. This was very good news and just in the nick of time. Matt had scouted out one site not far from the other side of Panama City where there were still frogs and additional experiments could be conducted as part of this new grant. If the disease spread much further into Panama the work would be finished for good. The remote Darien rainforest between Panama City and Columbia presumably contains the last areas the disease has not reached, but the eastern part of it is inhabited by drug runners and rebels and is not a safe place to work without an entire protective army. Going to the Darien was out of the question; we had a hard enough time getting funding, but getting support for a private protective army was out of the realm of possibility.

The disease, and getting more resources to study it

2009-12-07T10:40:00.001-08:00

While all the causes described above are factors in global declines of amphibians, the chytrid fungal disease is primary cause of the current cascade of extinctions in higher altitude regions throughout Central America. Every place that still has a diverse amphibian diversity associated with intact jungle is losing species of frogs.

Dr. Karen Lips has been the main scientist who has described this loss in Central America. By 2007, she had worked west of El Valle, at El Cope, Fortuna, and in Costa Rica for over a decade. She studied frogs intensively at these sites, and collected and identified as many species she could.
Karen was working on her dissertation in Costa Rica when the frogs suddenly disappeared. She was at Fortuna in Panama and the frogs vanished there. There was no obvious cause of mortality. The Fortuna site is old growth jungle, minimally impacted by humans.

Perhaps the most intense experience Dr. Lips had was in the forest at El Cope in 2004 when the disease front swept through the site. In a period of a couple of weeks most of the adult frogs died. Dead frogs were literally falling from the trees. She found species that she had never described before dying on the jungle floor. This was the first time she had seen these species because they spent all or much of their lives up in the trees where they were extremely difficult to collect.

The dying frogs all had the telltale sign of chytrid infections, sloughing skin. It is difficult to imagine how Karen felt in this situation. This was an area she had been studying for years, and she was watching the animals she had dedicated her career to die in front of her. Many people would have simply given up at this point. Karen kept going. She took samples and sent them out to experts to confirm that the chytrid was indeed present and causing the infection.

As time went on, Dr. Lips mapped the spread of the infection. It killed frogs in the high altitude rain forests in a wave of infection spreading generally from north to south in Central America (but from west to east in Panama because of the orientation of the country). The disease apparently can infect, but not kill lowland species. It is not lethal but can spread through these populations in warmer areas. When the disease is passed to the next mountain range where the temperatures are lower, the disease becomes fatal and extinctions begin again as it sweeps through populations of susceptible frogs.

There is no known cure for the fungal disease in the wild, but infected individuals can be treated with chemicals in the lab if they are not too far gone. Presently, the only way to save susceptible species from extinction is to collect them and grow them in aquaria where they are not exposed to the disease. Tadpoles have been re-released into the wild a few years after the disease has killed all the adult frogs. They die from the disease when they metamorphose and emerge as adults. Apparently, once an area is infected by the chytrid, the deadly fungus remains even if the frogs that it infects are gone.

Karen was a colleague of Matt’s at Southern Illinois University and she got Matt interested in the ecosystem consequences of the loss of these species. She knew the Central American frogs as well as anybody, but did not have the expertise in stream ecology to assess the effects on the other plants, animals and microbes in the streams.

Matt had the expertise in stream ecology, and his lifetime interest in herpetology (he has kept poisonous snakes since college) drew him into the project. Matt takes vacations to the deserts of Arizona and New Mexico to see snakes and lizards; his idea of a good time is turning over rocks to see what is under them. Even after he got bit (tagged) by one of his “pet” rattlesnakes he still kept them as pets. It was not until he had children that he thinned back his considerable collection of venomous snakes.

In one of their discussions, Karen told Matt how the rocks at Fortuna had gotten slippery and greener after the disease hit. At that point a light bulb went on and Matt realized that the loss of the extremely high density of tadpoles that occurred naturally in the streams could have important ecosystem consequences. Karen got Matt to go down to Panama and see her sites, and Matt cooked up the idea of assessing the ecosystem consequences of frog extinctions.

All researchers involved with this phenomenon realize the necessity of rapid work on the frog populations. Researching the Panamanian frog extinctions is essential because there will not be a second chance. Once the tadpoles are gone from a stream, they will not be back. This was a problem Matt could not ignore. Practically, this meant obtaining funding to work on figuring out the consequences of the disease that was killing the frogs. Now, the first round of that funding was almost gone, and more was needed to keep the research going.

Matt’s proposal to continue the work previously funded by the National Science Foundation received excellent scores, but it was rejected. This was not completely unexpected, but was still very disappointing. Less than five percent of the proposals in the competition were funded. Only one out of every twenty proposals written by the top academic researchers in the world was selected for funding by this program. The National Science Foundation funds the vast majority of the basic ecological research done in the United States.

The rejection put Matt in a difficult position. He needed to re-submit the proposal immediately to meet the next deadline (proposals were only evaluated every 6 months) and it was difficult to decide how to revise the proposal because the reviews were so positive. Nonetheless, he strengthened and re-wrote the proposal in only a few weeks. After thorough review by all the official project investigators (Karen Lips, Cathy Pringle, Susan Kilham) and associated participants (Bob, Alex, and me), it was sent off. The clock was ticking, and longer delays would make research impossible.

Science is not only about writing good proposals, but also about self promotion. When funding is so competitive, only the researchers that are able to publish their work in the top science journals in the world are able to continue getting funded.

Peer reviewed publication is the ultimate yardstick of scientific success. The system is set up to increase the probability that only the most robust and exciting science gets published in the journals. A scientist or group of scientists writes a paper, and then submits it to a journal. The editor at that journal reads it and decides if it is worthy for review. If it is, the editor obtains 2-4 reviewers to look at the paper. Each reviewer spends hours looking at the paper and searching for the tiniest flaw. They are also asked to rank the importance of the work (more subjective than answering the question was the work done soundly).

The editor reads the reviews of the papers and decides if it should be rejected, accepted, or to ask the authors for a revision that will be reviewed again. If one of the later two decisions is made, the paper and the anonymous reviews are passed back to the author who is invited to re-write the paper. This is a painstaking process but it does lead to a high degree of certainty that work is done well before it is published.

Species extinctions

2009-11-30T14:22:00.000-08:00

Of all the factors harming frogs and other species, the most ubiquitous and devastating is habitat destruction. Humans are radically altering more habitats than ever. Forests are cut down for lumber and turned into pastures or agricultural lands. Grasslands are plowed for agriculture leading to erosion and subsequent siltation of streams and lakes. Reservoirs flood streams and overuse of surface water and groundwater dries vital habitats. Wetlands and ponds are drained or filled for other uses. Urbanization, suburbanization, and exurbanization (domestic development outside of the suburbs) are destroying habitat for many species. Most land suitable for cultivation has been converted to cropland. Aquatic and terrestrial habitats are under assault every place on earth with even moderate human population densities.

These trends of global impact are global, with loss of most of the area of tropical rain forests (one of the top areas with biodiversity) predicted in the next few decades. The habitat destruction is causing extinctions at far greater rates than evolution can replace the species. I argue in my book, Humanity’s Footprint, that the pressures on natural habitats will intensify as population grows and our insatiable appetite for ever greater resource uses increases. Without drastic changes in the way we treat the natural habitats, extinction is inevitable for many species.

One of the strongest results of ecological theory and field research is that the number of species found decreases as the area of the habitat is decreased. Small islands have few species relative to continental regions. We know if we decrease the total habitat by 90%, we will loose around half of the species. Habitat destruction, even if it does not destroy the entire habitat, creates small islands of habitats. Ecological principles tell us that these small islands cannot support as many species as one very large area of natural habitat.

Frogs are but one of the species threatened by habitat loss; habitat destruction is a primary cause of a very rapid ongoing major extinction of plants and animals on Earth. This extinction is one of the 6 mass extinctions in Earth’s 3.5 billion year history. About 65 million years ago an asteroid slammed into the earth causing loss of about half the species in the oceans and many terrestrial groups of organisms, including the dinosaurs. Around 200 million years ago massive volcanic activity caused another mass extinction, and 250 million years ago 95% of Earth’s species were lost (the exact cause has not been determined). About 360 million and 440 million years ago there were two more mass extinctions.

Back to the species area calculation and how this influences extinction. Considering it is likely that we will decrease habitat by 90% in the speciose tropics, and that carbon dioxide increases in our atmosphere will continue to acidify the oceans and ultimately make it difficult for corals to survive in a warmer ocean, humans are causing an extinction that will rival other major catastrophes on earth.

The loss of amphibians has been compared to the loss of the dinosaurs. That was the last time a major taxonomic group was almost completely removed from the entire Earth’s fauna. The amount of terrestrial and aquatic habitats humanity conserves will ultimately determine the number of species that survive into the anthropocene (the current geological era of the Earth’s history where humans dominate the biosphere).

Amphibians arose around 400 million years and made it through four all four major extinction events that occurred since they arose. Modern frogs arose during the period dominated by the dinosaurs and survived the extinction that eliminated the dinosaurs. Now, amphibians, including frogs, are some of the hardest hit species of the current (human-caused) mass extinctions.

The Global Amphibian Assessment, the effort of a large international group of herpetologists, estimates that one third of the 5,918 known species of amphibians are endangered or extinct. In Panama, 55, or over 1/4th of the species, are threatened or extinct. Habitat loss and degradation affect almost 4000 species globally. Pollution is the second most common threat, and unknown causes, fires, and invasive species follow. Most of these causes are controllable or reversible. Disease is not.

No one factor can account for the disappearance or decline of frog species around the world. In some areas that seem pristine, there have still been substantial losses of frogs. In other areas the effect of chytrid fungal disease, UV exposure, pesticides and herbicide pollution, or habitat destruction are obvious. In most cases multiple impacts are occurring. Whatever the cause, frogs are becoming rare or extinct.

Amphibians are excellent indicators of ecological health. They are commonly surveyed by field biologists to indicate if an environment is degraded. Frogs and salamanders are among the first organisms to disappear when environmental damage occurs because most of them need both terrestrial and aquatic habitats, and their eggs develop in such an exposed fashion. Lakes, streams and wetlands where eggs and tadpoles develop integrate all the processes occurring in the stream.

Humanity should be deeply troubled that an entire group of organisms is disappearing from our planet, if nothing else this could indicate that the fundamental ability of earth to support us is being damaged. A broader moral interpretation, that other species have the right to exist, or for some, that humanity was placed on earth in part to take care of creation, provides reasons, other than the purely utilitarian reasons, to be concerned about amphibian declines

Introduced species and disease harming frogs

2009-11-23T13:13:00.001-08:00

Not only do humans introduce harmful chemicals into aquatic habitats, but they also add harmful species. We have purposefully or accidentally introduced many predators that harm frogs around the world. These predators include sport fishes and other frogs. Invasive species have been deposited into aquatic habitats everywhere people live or go to recreate.

Some people think fish from one area should be transported to other areas so the fisheries can be “improved” with more desirable species. Many people prefer fish they had in the area where they grew up to the native species where they live. Thus, we have common carp in the US. This was a regular food and sport fish in Europe, and people thought it would be good idea to introduce it here. Now, it is rarely caught as a sport or food fish in the US, but has spread across the country. Carp stir up aquatic habitats, destroys habitat for other fish, and eat most anything they can fit in their mouths. Likewise, people have introduced bass into many habitats, and trout wherever they can.

We have introduced relatively large predators into virtually all major drainages of the world. Many of these introduced predators will eat frogs or tadpoles. Predator introduction is one more factor contributing to amphibian declines.
A very important example of an introduced species, with respect to amphibian declines, is the cane toad was a native to Central and South America. It has been introduced in many places in the world for pest control. It was introduced into Australia in an effort to control beetles that are pests on sugarcane. Unfortunately, the toad is ineffective against the pests it was introduced to control; the toad lives on the ground, and the beetles are higher up in the sugarcane.
Cane toads are very toxic, native snakes die when they eat the adults, and fish die when they eat the cane toad tadpoles. Having no evolutionary experience with the introduced toad, Australian predators continue to try to eat both the adults and the tadpoles. In addition, the large toad will consume any smaller frogs or other amphibians it comes into contact with as well as any other prey that can be gulped and squeezed past its jaws. The cane toad is one amphibian that, unfortunately, is not in decline.

Bullfrogs have spread from Central and Eastern US all the way to California. Because its eggs and tadpoles are not palatable, this is one of the few species with tadpoles that can avoid being preyed upon by fishes. Being the largest North American frog, bullfrogs can ingest mice, other frogs, toads, worms, salamanders, and many types of insects. These frogs may be hastening the disappearance of some rarer species of frogs, particularly those found in California. The bullfrog is resistant to the chytrid fungal disease to which many other frog species are susceptible. It may actually serve as a reservoir to move the fungus around (known as a vector to epidemiologists). Introduced species not only include animals, but also include diseases.

The chytrid fungus, Batrachochytrium dendrobatidis, causes a lethal infection to many species of frogs. The disease could have initially been spread by African clawed frogs, although multiple introductions have probably occurred. These frogs were transported around the world to be used for pregnancy tests and as research species (such as in the work of Dr. Hayes mentioned previously). The theory is that some frogs escaped and then passed the disease on to local amphibians. The African frog and many frogs from warmer habitats are resistant to the disease, but many other species of frogs are not. The resistant frogs can carry the disease from one habitat to the next.

The fungus infects the frog’s skin and causes a catastrophic loss of ability to control water balance across their skin; frogs need healthy skin to survive and are particularly sensitive to factors that alter the exchange of moisture and oxygen across their skin. The fungus causes the frog’s skin to thicken to the point where they suffocate. Diseased frogs look terrible with their skin sloughing and their beautiful colors hidden behind a thick layer of infected skin. The fungal disease seems to be hitting particularly hard in Central America and Australia, though these are the areas where the main study on the effects of the disease has occurred, and it is possible that other areas have also been hit that are not as well documented.

Global warming might interact with the chytrid fungal disease. Even a slight warming of climate represents a significant change in temperature in the tropics, where temperature extremes are not so wide. Warming paradoxically leads to cooler days at higher altitudes in Central America by pumping more moisture from the oceans and increasing cloud cover. Cloud cover also causes warmer evenings. Dr. J. Alan Pounds, of the Monteverde Preserve in Costa Rica (the same preserve that used to be home to the Golden Toad), found that these climate changes are creating the perfect conditions for spread of the chytrid disease. Over 100 species of frogs have probably gone extinct in Central America from the combination of local effects of global climate change and the disease. Frogs have experienced periods of warming and cooling over their evolutionary history, but never in concert with the chytrid fungus.

Human pollution and frog declines

2009-11-16T10:27:00.001-08:00

The impending loss of the frogs in Panama led me to delve more deeply into the literature on amphibian extinctions. The decline of amphibians is global pattern that was noticed by individual researchers comparing observations from around the world. The researchers at international meetings realized that one talk after another was telling the same story, from sites around the world. Some of these sites were pristine, others heavily influenced by humans. The picture that has emerged over the last few decades as a result of the herpetologists realizing the global pattern is sobering, but is also a testament to science as an international endeavor and the broad geographic approach that leads to generalizations that could not be reached if research was constrained to one small area.

In the 1990’s, Andrew Blaustein, at Oregon State University, began to see declines in the species of frogs he was studying in the mountains of the Pacific Northwest. He understood that ultraviolet radiation (UVR) was increasing world-wide because of global ozone depletion in the upper atmosphere. Chlorofluorocarbons used in aerosol cans, now being phased out from use in air conditioners, refrigerators and freezers, enter the air at ground level and work their way into the upper atmosphere. Here, ozone that forms naturally absorbs the ultraviolet rays from the sun. The chlorofluorocarbons destroy the ozone that protects life on the Earth’s surface.

Blaustein hypothesized that increased UVR might be harming amphibians. This hypothesis was reasonable because UVR is known to cause damage to organisms and most amphibians lay their eggs in shallow water where they are exposed to high levels of sunlight and UVR. At higher elevations, UVR is more intense, plus it is possible that amphibians were already close to their upper tolerance levels before UVR started to increase. While these animals did evolve under such exposure, it was not certain if increases in the levels of UVR were responsible for harming the frogs. A series of experiments confirmed that the UVR increases similar to those caused by global ozone depletion lowered survival rates of eggs. One piece of the puzzle was starting to come together.

So this begs the question, will UVR increase or decrease in future years? The use of CFC’s has decreased since the Montreal Protocol was signed in 1991. The decline in stratospheric ozone has led to a halt in the loss of ozone, but still, almost 20 years later, the upper atmosphere has not healed itself. Now we know part of the reason why, nitrous oxide produced as a byproduct of agricultural nitrogen fertilization is also damaging stratospheric ozone. As humanity struggles to feed more and more people, we have been and continue to use ever more fertilizers. Some of this fertilizer is converted by bacteria into nitrous oxide, and this gas works its way into the upper atmosphere, destroying ozone and allowing more UVR to pass to the surface of the earth. Thus, UVR will continue to be a problem for some species of amphibians.

Subsequent research by Carlos Davidson and colleagues from the University of California at Davis established the role of pesticides in amphibian declines. This research examined the declining red-legged frog in California. Careful analyses of data on red-legged frog populations from 237 sites revealed that one of the most important factors in population declines was distance downwind from agricultural fields. Other research over last decades has demonstrated that pesticides and other volatile chemical contaminants can be transported substantial distances and in some cases concentrated by atmospheric processes. High mountain areas as well as arctic habitats are areas where volatile pesticide pollutants are concentrating. These are habitats that seem pristine.

Amphibians are particularly sensitive to these contaminants because their eggs require direct exposure to water, and water carries the contaminants from where they are deposited on land and water upstream, to the eggs. The potential for concentration of these contaminants in the food chain is well recognized; almost a half century ago Rachel Carson wrote “Silent Spring” and illuminated the propensity of these toxins to bioconcentrate and cause environmental harm. Before Silent Spring, most people did not realize that very low levels of these chemicals added to the environment could have adverse biological effects because they were concentrated by natural processes occurring in all ecosystems. Now, the effect could be harming species of frogs and contributing to their declines. Furthermore, a new and unanticipated threat of the pesticides has been documented.

Dr. Tyrone Hayes of University of California Berkeley, was conducting experiments on a common weed killer, atrazine. Seventy-seven million pounds of this herbicide are applied each year to fields in the US. The experiments were designed to detect minimum levels of atrazine which would cause negative effects on aquatic animals. In these experiments, frog eggs are exposed to a range of concentrations of the atrizine to extremely low concentrations that nobody would think had any effect on any organism.

He was surprised to find that vanishingly small concentrations of atrazine feminized leopard frogs while they were developing in the laboratory. Then, Dr. Hayes and his graduate students found similar results in field experiments. Further investigation showed that African clawed frogs exposed to water with as little as one part per billion of atrazine developed improperly, with inhibited larynx growth. A larynx is important to the males of many species of frogs because singing is how they attract mates. The question was how could these compounds be active at such low concentrations? This was a particularly vexing question because negative effects were expected at higher concentrations, and the effects diminished as concentrations decreased. Then, suddenly at very low concentrations, negative effects on the animals popped up again.

The answer is that the chemicals such as atrazine mimic hormones that all animals use in cell-to-cell communication. These compounds signal cells in developing animals to take one or another developmental pathway. The compounds are only biologically active at very low concentrations; animals only produce very low concentrations of hormones to signal developing cells. Many compounds made by humans and released into the environment mimic estrogen, a hormone with strong influence on sex characteristics of both males and females as embryos develop.
Ecoestrogens have been implicated in a number of cases of feminization of wildlife. It is not currently known how these compounds influence development of human embryos, and potential effects of ecoestrogens on humans is an area at the forefront of environmental concern. In this case, amphibians serve as the canaries in the mine; they are quite sensitive to pollutants in the water because they develop fully exposed to the water.

The increased used of fertilizers in agriculture was already mentioned, but more intensive agriculture also requires more use of pesticides. The use of pesticides has skyrocketed in the decades since their widespread introduction in the mid 1900’s, and we have fed the world in part because we have limited some pests (insects and weeds) by using such compounds. The chances that use of these compounds and their release into the environment will decrease in future years are slim.

Other aquatic pollutants could be harming frogs as well. Mercury concentrations are so high that many fish from waters in the US and Europe should not be consumed. Even fishes from the mighty and mostly remote Amazon can have high enough burdens of mercury that regular consumption is not advised (gold mining upstream causes mercury contamination). Mercury can harm all animals, and less attention is paid to frogs than fish with respect to contamination. This is because fewer people consume frogs than fish.

Back to the fertilizers, further work by Dr. Blaustein demonstrated that nitrite, a common byproduct of runoff from fertilized agricultural lands, also harms development of frog eggs. Nitrate contamination downstream of fertilized areas is common with very high concentrations in the rivers and streams of many developed lands, particularly Western Europe and the Midwestern United States. To make things worse, combustion of fossil fuels leads to substantial amounts of nitrogen deposition and causes nitrogen contamination of many aquatic habitats. The effect is particularly strong near industrial or urban areas. More pieces of the puzzle of global amphibian declines were falling into place.

Saying goodbye to the frogs

2009-11-09T09:04:00.001-08:00

As we continued working at Rio Maria, it became more important to me to take in the experience of watching the tadpoles swarming in the stream and the constant movement of small frogs scattering as I walked down the jungle trails. This place was the “zen” of frogs and it was easy to sit and meditate on them. Our discussions more frequently turned to the impending disappearance of the frogs and the prospects for saving other parts of the jungle.

While the road to the research site from El Valle was tremendously difficult, it connected with a road that came up the other side of the volcano from the coast highway. This area up high on the slopes of the volcano had seen years of agricultural use, mainly cleared jungle for pasture. This development was patchy, but now it was being converted into high priced houses and ranchettes for wealthy Panamanians. The site also attracted retirees from the US and Europe who realized their money could buy more in Panama than it could at home. The site also attracted retired “snow birds” who migrated down to avoid the cold winter, and then closed up their homes in Panama and returned to the States in the summer. The mountain sites were attractive because of the fabulous scenery and the pleasant year-round temperatures. Not as hot as the lowlands, yet never actually very cold. The land of eternal green and spring was very attractive indeed.

The bulldozers were rolling. It was obvious that development was as much of a threat to Rio Maria as the fungus that was creeping toward the frogs, but the developer claimed that the Rio Maria valley would not be developed and the valley and its wildlife would be preserved. This was good news because habitat destruction would take the majority of the plants and animals with it, leaving only the few weedy species that could coexist with humans. Diversity would be far less than in the current jungle.

Cathy Pringle needed to get back to teaching so she took a shuttle bus to the airport. After she was gone we found a pair of her dirty shoes and socks in the back of one of the pickups. It made sense, who would want to carry wet socks on a day long travel home? We now had proof of the rumors about her always leaving behind socks and we all got a good laugh out of it. Someone in El Valle would certainly put them to good use after a good washing.

We spent a lot of time training Piet, Heidi, and Edgardo who would remain behind to finish up the work and continue monitoring the stream. They needed to learn how to collect all the samples and what to do if things did not work out quite right. It was as important to teach them the concepts behind what we were doing as it was for them to learn specific technique. What if sampling is put off for a day, is that ok? What if the pump breaks and samples cannot be filtered right away? Understanding the research allows such questions to be answered. Fortunately, we could maintain contact with them via e-mail and cell phones from El Valle.

Before we left, we also tried to process as many samples as possible to take back to the US. The routine of field work associated with this type of experiment is the same regardless of the setting. Samples need to be dried and weighed, some of them ground up. Water needs to be filtered and analyzed. Voucher specimens need to be preserved for formal identification in the laboratory. Who was bringing what sample back to the states was important and it was all recorded.

The last day at Rio Maria, we turned off the tracer drip. Then we had to wait for the lines to get cleared out, so Alex and I took a walk to the stream above. It was nearing dusk and the frogs were becoming more active. On a rock in the middle of the stream we saw a smaller male golden frog perched on the back of a larger female. This behavior is called anaplexus, and is how the frogs mate. The males are reputed to ride around on the backs of the females for up to two months before an appropriate breeding site is found. I suspect that this is just legend, but you have to admire the tenacity of the male. All the while, the male strokes the female’s chest with nuptial pads on the fingers of their forelegs. This has to be the longest foreplay in the animal kingdom. Eventually the male fertilizes the eggs and the female lays them. This extraordinary courtship continued in spite of the impending demise of these frogs.

We felt like this was the last we, or anybody else, would witness this behavior of this species in the wild. The last chance to see can be profound, and Alex and I were both lost in our thoughts about what the image meant to us.

The trip back to the US from El Valle was uneventful, with a good shopping trip to an artesian market and a night at a very good seafood restaurant in Panama City. We got up very early the next morning to give us plenty of time to make our 8:00 am flight.

The flight back was ordinary; it was amusing to watch Bob talk his way through US customs with more than his allotment of liquor to avoid paying import tax. The customs guy told him not to ever do it again, but let him through. If he knew how many more bottles Bob had in his checked luggage, he might not have been so nice about it. The best strategy in customs is, never lie and never give more information than asked for. Considering we were bringing samples back into the country, even though it was completely legal to bring the types of biological samples we had back, an overzealous customs or agricultural products inspector could delay us long enough to cause us to miss the next flight out.

Before I knew it, we were back in the US and into the world of strip malls and fast food. Culture shock, even though we were only gone for a couple of weeks, still make a mark. The main objectives of the project now fell to Matt and Piet. Matt needed to obtain more funding to repeat the trip after the disease swept through Rio Maria and the El Valle region, and Piet needed to work through most of the samples we brought back. I had my expensive bottles of rum, a batch of digital photos, and memories of Panama, El Valle, and the frogs of Rio Maria.

Our first task on the project after returning was to obtain funding to get back to Panama and complete our experiment. We agreed that we would find a way to bootleg the work out of other projects if we needed to, but could not do as good of a job without substantial research funding. This job fell to Matt because he was the leader and wrote the first grant. He was a bit spoiled because the first grant had been funded the first time it was submitted, and it was also the first grant he had submitted to the National Science Foundation as lead investigator. Such success is rare, but we were optimistic about requesting the next round of funding. The additional funding seemed highly deserved because of the urgent nature of the research, the unique and powerful angle of using the nitrogen tracer experiments to test how the effects of tadpole extinctions in the streams cascade through the rest of the ecosystem, Matt’s skill at grant writing, and the assistance of the rest of the group.

The next deadline for grant applications was 5 months after our return and Matt wrote the proposal and circulated it around to the rest of the group for their input via email. Writing a grant proposal such as this is not a trivial amount of work. The body of the proposal was 15 single-spaced pages, and including all the necessary information to satisfy the dozen or so reviewers in this length of document is quite a trick. Completion of many pages of forms is also required and every detail of the proposal must have references from the scientific literature to verify statements and show that adequate procedures will be used. Multiple investigators from multiple institutions requires numerous budgets each with their own requirements and bureaucracies that need to be navigated for many signatures. After a long process, the proposal was polished up and submitted. Then we had to wait for the 5-6 months it takes for grant proposals to be processed.

The jungle stream at night

2009-11-02T08:17:00.001-08:00

The next few days were filled with technical details of working in the field and doing lab work in the evening. We got time to call our families at home and eat some nice meals. A highlight was when Heidi and Scott Connelly took Piet and me on a night herping (looking for amphibians and lizards) expedition. I had been taken on a night-time herping expedition in Costa Rica many years before.

The expedition leader on the Costa Rica trip was a professor with lizard-like eyes; they bulged out and he rarely blinked. He carried his cigarettes in one plastic bag tucked under his belt. He had another large bag stuck in the other side of his belt to hold the snakes and frogs he caught on the trip. His plaid polyester pants tucked into the top of his rubber boots and shirt button down polyester shirt, as well as his umbrella, seemed odd at first but his enthusiasm for the animals was contagious. We had a fantastic night tromping through the jungle swamp. He would shine his flashlight and catch the flash of reflective eyes and crash into the swamp after it. He would come back beaming with a poison snake in his hand, or a frog or lizard. First thing the next morning we looked at all our prizes. I jumped at the opportunity to go night herping again.

We secured our headlamps, grabbed our cameras and drove to a local stream as the sun went down. As we walked to the stream Scott and Heidi talked about the incredible diversity of frogs in the region.

In addition to the golden frog are several species of glass frogs. These frogs are clear because they have little pigmentation. You can see their hearts beat by placing a light behind them. They lay their eggs on leaves overhanging the stream where the eggs are less susceptible to egg predators. When the eggs hatch, the tadpoles drop into the stream.

We talked about the tadpoles that live deep in the leaves at the bottom of the streams. Accumulations of leaves on stream bottoms are very low oxygen habitats and the tadpoles have tremendous amounts of hemoglobin (the protein that caries oxygen in our blood and that of other invertebrates). They are bright red when exposed to oxygen. This is a somewhat common adaptation among animals. In temperate lakes, midge larvae known as blood worms inhabit the low-oxygen sediments. They are mostly colorless in their native habitat, but when they are exposed to air at the surface or highly oxygenated water, they turn bright red as their abundant hemoglobin binds all the oxygen it can.

Panama has 195 documented species of amphibians. This is over half the number found in the US in a country slightly smaller than the state of South Carolina. Thirty four of these species are found nowhere else (are endemic) and most are restricted to Central America. Panama is an amphibian-lovers paradise and El Valle has historically been a Mecca for people wanting to see Panamanian frogs and other amphibians. Frog societies plan meetings and collecting trips commonly with El Valle as their base of operations.

During the day, brightly colored toxic frogs such as poison dart frogs are common. These frogs practically glow in the low light of the tropical forest. Their bright colors are a signal to predators that says “I am poison, eat me and you die”. Other species, also brightly colored, look like poisonous species, sending the same signal to predators, but are not toxic. This mimicry allows the frogs to avoid predation without having to synthesize costly toxic chemicals. The two types of frogs are balanced in population numbers, because if there are too many of the non-toxic species, predators will start eating and frog with that coloration. So, the non toxic frogs take advantage of the toxic species that they mimic. Evolution has lead to some amazing things, and “cheaters” are a fact of life!

At night the more cryptically colored frogs come out to forage. Their calls filled the stream bottom as we worked our way up the rocky stream channel in the dark. Our flashlights were reflected by the eyes of freshwater shrimps as long as your hand. These shrimp are very skittish, and they scuttled out of sight under rocks by the time we were within 50 feet. Freshwater shrimp are common in tropical streams. Some species have been taken into captivity for aquaculture, particularly in south-east asia. Some of these shrimp play the part that crayfish (crawdads) fill in more temperate streams (omnivores), but others specialize on fine or coarse particles, or algae, or other food types. The shrimp are most common in smaller streams where large predatory fish will not eat them.

Moths bigger than my hand were hanging over the stream. We saw an occasional snake foraging through the underbrush near the edge of the stream; preying on the abundant frogs. The jungle shows a whole different face at night, animals scurry off through the darkness, bats dart around over the stream, and there are spiders the size of a salad plate with eyes that glow in the darkness when your flashlight happens to strike them. Scott and Heidi discussed how the frogs probably would not be around the next time I came back. We left the stream to get back to our hotel muddy, sweaty from our walk, and thoughtful.

El Valle Open Air Market

2009-10-26T10:43:00.000-07:00

At first glance we could tell that enough rain had not fallen to cause a flood bad enough to scour the channel, wash away our expensive equipment, and scour the channel badly enough to ruin our experiment. Several large yellow and black frogs jumped on the stream banks; the golden frog of Panama was doing well here for now. They were not concerned about our presence. We walked another quarter mile up the slippery muddy trail to where the pump was dripping in the tracer solution at a constant rate. We changed the battery and added fresh tracer solution. It was good to get the weight of the tracer solution out of our packs. Tadpoles were swarming in the stream as they had been the day before, the slightly increased flow and cloudy water from the rain was not bothering them apparently.

Everything looked in order so we ate lunch and headed back. By the time we started back the rain had cleared and the tropical sun had started to beat down. It heated up quickly and the road was steep from Rio Maria up to the volcano rim, to where it would drop back down into the crater and wind down to El Valle. We started regretting that we had not thought to bring more drinking water. We slid our way down over the slippery clay on the steep hill that had stopped the trucks in the morning. Our ride had not arrived at the bottom of the hill, so we started down the road toward the hotel. We hoped we would not have to walk the entire 5 additional miles back without a lift. After a bit we reached the area where there were farms and passed a place where a citrus tree had dropped its fruit into the road. These green fruits were not quite grapefruits and not quite oranges. Nonetheless they were a welcome and delicious source of liquid as we made our way toward El Valle. Another half mile down the road one of our trucks pulled up and we rode back.

That afternoon it was still sunny and we made our way down to the open market in El Valle. It is a mixed tourist and local market with booths selling everything you would need to live in the area, as well as many trinkets, locally produced and imported art objects aimed at tourists. While some may consider a department store a modern invention, the city market has a comparable array of goods crammed into the same amount of space; many more merchants participate in selling goods. We bought more food and some gifts for our families. I noticed fruits not common in the US (custard apples, nance) as well as those that are (pineapple, oranges, and grapefruits). The produce was fresh and much better than commonly found in large supermarket chains.

Items mainly for tourists included the well known traditional molas, an appliqué tapestry made by Kuna Indians and transported from the Caribbean coast to the north. Tagua nuts are about the size of a lemon with an ivory colored interior that hardens after being carved and exposed to air. The tree in native from the Southeast of Panama into Northern South America. Before plastic buttons, the nut was commonly used to make buttons that looked like ivory. Using these nuts to produce statuettes is an environmentally responsible solution for those who like ivory carvings. Commonly, intricate animals are carved in the tagua nuts and the carving is painted.

Natural animals are a common motif in these artisan-produced objects and most are fairly realistic. Many of the Tagua nut animals are extremely accurate representations, both in terms of color and proportion (although there are some inferior products to be found as with any craft that is sold for tourist consumption). These crafts suggest that the Panamanian artists, at least, value their wildlife. If they were only carved for tourists, attention to details of form and coloration of local spiders, frogs, and snakes would be unnecessary, as most tourists have no idea what the real animals look like. There are also cocobolo carvings of animals, and palm-fiber baskets and purses.

I was particularly interested in how many golden frog statuettes were available, some were tagua carvings, but most of the frogs were cheap plastic versions. The golden frog in Panama is the equivalent of the bald eagle in the US. The population crash of the bald eagle ultimately led to banning use of DDT in the US because people were upset the national bird could be lost. The toxin DDT concentrated in their eggs and made them so thin they would crack. The US people found this unacceptable and refused to allow use of DDT.

The Panamanians are experiencing the demise of a cultural touchstone to their country, and they can do little to stop it, as will be discussed in the next chapter. I also wondered if the statuettes would still be available in a few decades and how much they would look like the actual frogs. Many of those available in the market that day were true to the morphology and coloring of the golden frog. Others were depicted smoking and drinking martinis, kitschy tourist bait. Cultural evolution and no real comparison alive in the wild could ultimately lead to only a stylized version being sold, if any.

We watched as tourists disembarked from large air conditioned busses and flooded into the market only to leave an hour later. Overweight tourists haggled with the market vendors; many had cameras with lenses over a foot long or expensive digital video cameras. It was a typical scene in a tourist town. The atmosphere was definitely more relaxed after the last bus left. It was humorous that I too was a tourist, yet somehow felt superior to these bus tour participants.

That evening, after dinner I noticed that a television in the bar across the street was playing the super bowl. Passing up this bit of “culture” from home proved too difficult and we decided to go in. Entering the bar I noticed the gangs of tough looking youths hanging around outside. There were very few women in the loud and crowded bar; obviously the few females there were attending in a professional capacity. These professionals were not the women young men would bring home to meet their mothers. In general, this was one of the rougher bars I had been in. Feeling a bit insecure, I stayed near the bar with my group and watched the game.

Suddenly it struck me… nobody was smoking. I asked about this and was told that smoking had been outlawed inside public buildings in Panama a year before. Here I was in a rougher bar than any in my small town in the Midwestern US, yet smoking was not allowed here while such a ban in my home town occurred 2 years later. Some places in Panama are more socially progressive than parts of the US. This observation led me to realize that relationships between society and health were more complex than I had considered.

Later, I discussed the idea of social responsibility for health and environment with Heidi. She has an interesting perspective having lived in Panama for the last half decade, but growing up in the US. She mentioned that the Panamanians were also very concerned about global warming and most were unhappy with the way the US has been dealing with this issue. They felt that the US was burdening them with environmental problems associated with global warming without spreading the benefits of their extravagant lifestyles to the Panamanians. Essentially they felt the US people were burning the fossil fuels and they were paying the price for our consumption.

I don’t remember who won the football game. I do remember that the next morning I got my luggage! We had another working pump and I had some clean clothes. The clothing I missed most, other than clean underwear, was the quick dry pants. Quick dry clothing in the tropics is far superior to denim jeans. The thin synthetic fabric protects you from insects and the sun, but is not too hot. Given the amount of rain in a rainforest, the quick dry feature is advantageous. Plus, my quick dry pants looked a good bit nicer than the droopy jeans I had been wearing non-stop for the last 5 days.

Bannanas, filtering and lost luggage.

2009-10-19T08:48:00.001-07:00

Working in the dark is difficult at best and potentially dangerous in the jungle. The road back would be even more treacherous in the dark than the nighttime jungle, so we finished up in time to get our gear back into the trucks and drive back to the hotel before dark. Edgardo called about my luggage when we returned, but it had not yet been found. Back at home my wife had been working on tracking down my luggage, and she had made no progress either. At this point we also received word that a member of our planned research group, Karen Lips, had also lost her luggage and was staying in Panama City to attempt to retrieve it.

One last member of our research team, Cathy Pringle, had arrived at our hotel that afternoon after coming in on a different flight. She is an internationally respected researcher, a professor at the University of Georgia and has been more involved in advancing the study of tropical streams than almost any other researcher in the world. She has worked across the Caribbean, in Costa Rica, Panama, the South Pacific and Madagascar.

If somebody in the research community mentions “tropical stream ecologist”, Cathy is who comes to mind. She is an innovative person who knows how to get the resources she needs to do the research. Her brash and gregarious nature and deep desire to understand and preserve tropical streams have taken her to parts of the world that few have experienced. These qualities make her an extraordinarily interesting person to work with. She is an original and hard working researcher. I had worked with her for years on issues related to our stream ecology society. Among other things, Cathy loves little tasty tropical bananas and shopping. She has a twinkle in her eye and a mischievous nature, as well as a reputation for leaving pairs of dirty socks behind everywhere she travels. She also is the exception to the rule about not wearing sandals while working in the jungle.

Speaking of dirty clothes, mine were becoming a bit dodgy; I washed out what could be washed and we headed into town for dinner. After dinner we broke out a little rum, mixed it into some pina-guava juice, and got down to doing our chemical assays. Some of the local help thought the party would be fun but when they realized we were actually doing lab work and calculations for our experiment the next day, they drifted off to their own rooms. After a late night of planning, we turned in, thinking about our getting going early the next morning.

I pulled on my sodden clothing the next morning, followed by the usual fruit and cereal breakfast, and of course, my diet coke. The coffee drinkers were enthusiastic about the fantastic Central American coffee, and I almost regretted not having taken up the habit, the smell at least was quite pleasant. After repeated runs through our equipment lists, and a longer delay than we planned to discuss the experiment (more questions, it turns out Cathy, as well as Piet, is really big on questions), the group piled into the trucks and we started back to the field site. Matt had mentioned to me before we left the States how the steep rocky roads started to wear on you after a week, I was starting to understand what he meant, and this was only the second day of driving stiff-suspension 4 wheel drive trucks bouncing up and down the hills.

We got to Rio Maria without major problems and carried our gear to the upstream point of the nitrogen tracer experiment. We needed to pump trace nitrogen into the river continuously for a week, and that required us to carry 5 gallon carboys full of the chemical that we had dissolved in water the night before, a half mile up the stream. Five gallons is over 40 pounds. The jungle trail was always slippery, and the added weight of the carboys did not help. Our footwear was knee-high rubber boots which do not have the best traction. This was hard work, and we were grateful we made it before the heat of the sun peaked.
There were more samples to collect, so we had another full day of work ahead of us. The samples were taken and the tracer experiment started as planned. We had some down time between measurements and this time was used to crack open tins of food and crackers for lunch. I had brought my underwater camera and started to take pictures of the tadpoles in their native habitat.

Underwater cameras have recently become fairly inexpensive and easy to use with the advent of digital technology. They are a fantastic piece of equipment to have, even if underwater pictures are not desired; the jungle is always humid and drippy and the protection is helpful. I had spoken to professional photographers about using cameras in the tropics and they mentioned that fungus and moisture always work their way into lens systems and eventually fog them. At least the underwater cameras are protected from this and the desiccant packs placed in them help even more.

Also in down time, water samples needed to be filtered. We had only manual vacuum pumps and needed to filter large amounts of water to collect particle suspended in the water onto filters so they could be analyzed, and the filtered water also needed to be saved for analysis. The pumps kept breaking down; unfortunately my hand pump was still in my lost luggage. Emergency repairs with duct tape and epoxy were all that allowed us to keep using these pumps. Cathy Pringle is one of the few full professors I know that really enjoys sitting in the sun next to a tropical stream, eating the occasional small sweet tropical banana, and pumping water samples for hours. This is probably a good release from the hectic pace she maintains back in the states at the University running her large laboratory. We willingly allowed her be the official jolly field filterer.

As 6:00 pm approached (sunrise and sunset time are certainly predictable in the tropics) we had packed our gear and put some brush over the trail to obscure our path up Rio Maria. We knew that the thousands of dollars of gear we had up the stream would be worth nothing to the locals, but could not be certain that the gear would still be there the next day if we advertised the location where we were working. Making our way up the road carved into the wall of the extinct volcano, the setting sun illuminated the jungle draped rock pinnacle a few miles away, a breathtaking end to a good day in the field. All that was left was dinner, drinks, and more filtering and analyzing samples that evening. We also started entering data into our computers and making certain that the field notes were all organized with their data duplicated against loss.

The good news when we got back was that my luggage had been found and delivered to the bus station. The bad news was that it was Saturday night and the station was closed on Sunday. Try as we might we could not get the employees of the bus company to come in and open the station. I offered bribes, but they were worried that violating regulations would cause them to lose their jobs. My bribes were not big enough. Of course Edgardo was patiently mediating all this; I purchased minutes for his cell phone to reimburse him for all the calls he graciously made in pursuit of my luggage. The restaurant we ate at was right across the street from the bus station, so we went to look for my bag. Sure enough I could see my suitcase sitting there. My filthy jeans seemed a bit worse for the wear and did not smell pleasant. My trip mates would probably say they stunk. My suitcase sitting a few feet away, yet unattainable, did not help things much in my mind.

The next morning it was raining. Our experiment was taking place during the “dry” season, but we were in a rainforest. The rain made us very nervous because we needed to be certain that Rio Maria was not flooding and ruining our equipment and also we needed to carry fresh tracer solution and check that the pump delivering the solution to the stream had adequate power and was working properly. The clay parts of the road to Rio Maria were very slick from the rain.

Scheduling issues related to the rain caused tensions to rise that morning. Also, some of the crew was uncomfortable with the fact that all of the drivers were not experienced with four-wheel drive and manual transmissions. All our four-wheel drive trucks were manual, and driving them on the treacherous mountain roads was not a task for beginners. We got all the passengers sorted out and started up the road in four wheel drive (we usually did not lock in the hubs for the four wheeling until we got to the really steep bits but we needed it as soon as we left the pavement this day). When we reached the steep part, everyone but the drivers got out. Edgardo then tried to drive up the hill. It was a disaster. He would spin all four wheels up about quarter way and then get stuck, only to slide backward down the hill. Considering the steep drop-off on one side of the road, sliding in the mud backwards was not exactly safe. We were lucky none of the trucks, or for that matter, the people, were damaged.

Alex, Bob and I decided we needed to walk in to check the experiment. We packed up some tracer solution, batteries, sampling equipment, lunch, and put on our rain gear. A time was set for a truck to come back and pick us up. Getting up the steep bit was difficult, even on foot. The only good footing available on the greasy road was protruding rocks or vegetation growing along the edges. We slipped our way up that hill, and the next, and the next, to the top. Then we started on the road as it traversed down the outside of the ancient volcanic crater.

Every once in a while Alex would point out something interesting that I had never seen before. The guy is a fanatic for leaf-cutter ants and insects of all kinds. He has a fantastic eye for biodiversity, and by the end of the trip I realized that he is one of the best natural historians I had ever been in the field with. I have been in the field with quite a few well trained, expert biologists. We could hear birds and frogs calling in the jungle, but the thick mist obscured most of their locations. The frogs were calling even more vigorously than the day before, if that was possible, because the rain stimulated them. A couple miles later we were at Rio Maria.

Danger in the jungle

2009-10-12T10:24:00.001-07:00

The rainforest around Rio Maria is not pristine. The area was logged 50 years or more ago. Large birds that once flew above the trees, such as the Scarlet Macaw, are gone, most likely captured by locals. No howler or spider monkeys are left in this jungle, and the collared peccary (javelina) is not found as it once was. These mammals were probably taken for food or the pet trade by people. This region is not protected and is too close to human habitation for most large animals to survive collection or hunting. Still, the small plants and animals are very diverse and the jungle here has much to offer to biophilic (biology loving) visitors.

The ability of the jungle to rebound from logging is a direct consequence of the millennia that these trees and associated plants have interacted with humans. Panama has been inhabited for at least 11,000 years. The indigenous people have a sophisticated culture, that among other things, developed unique and ornate styles of pottery. In this region, called Coclé, the indigenous culture required rotating agriculture which would have been slash and burn. The jungle in the flat parts around Rio Maria has very likely, over thousands of years, been repeatedly been cut (slashed), burned, cropped and after a few years left to return to jungle to recover its fertility.

While the jungle around Rio Maria was missing some components of an extensive, old-growth, tropical rain forest, it still had incredible diversity and beauty. Only in recent history have humans developed the machines and population densities to completely remove jungle from tremendously large areas. There is little hope the diversity will return to the areas of massive deforestation as it does to the small patches that are cleared for a few years by native agriculturists under slash and burn cultivation. We know that very plant and animal diversity could coexist with the traditional native practices, but those days are now gone.

Working in the forest requires caution. Those who work in the jungle say that falling trees and limbs are the greatest danger. If you are unlucky, one will fall and hit you in the head. If you spend much time in the jungle you will hear limbs falling, and the trees in even this re-grown rain forest can be a couple of hundred feet high, so the branches can gain considerable momentum before they strike an unlucky researcher below. Each tree limb plays host to numerous epiphytes. These epiphytes include the orchids and a number of what we commonly see as houseplants in homes in developed countries of temperate climates (for example ferns, spider plants). These plants take advantage of the limbs of the trees to grow higher in the canopy where they can get far more light than they could on the forest floor. The mass of plants on each branch grows to a greater and greater mass. Eventually the weight is too much for some branches to bear and they come crashing down.

The large trees tend to have shallow root systems that are spread across the jungle floor to intercept nutrients that reach the soil there. Tropical jungles generally have very poor soil and organic materials containing nutrients are rapidly degraded and the nutrients they contain scavenged quickly. This is part of the reason for slash and burn agriculture; the vegetation that is cut down and burned provides nutrients for a few years, but the soil is not productive so the fields are abandoned after a few years. Unfortunately, if cropping continues the soil becomes so
unproductive that not even the jungle can return.

The shallow roots are not good at holding up the trees, and this is made up for by the buttresses (broad supportive ribs) that extend away from the base of the trunks. Even with the buttresses, a large tree will fall occasionally. Because it is connected to others by dense vines, not only will it smash the trees directly where it falls, but also the falling trunk will take many smaller trees down with it.

Tarzan movies are not very realistic, but there really are vines that could support a large primate that crisscross the jungle canopy. We tested this as college students in the jungle finding vines on hills that would allow us to swing high into the air.

When a large tree falls and takes others down with it, the light gap that enters the forest will allow new rapidly growing trees to grow up into the canopy. This process is part of what leads to the tremendous tree diversity in the tropics; the light gaps promote species that would not be able to compete in the dense closed canopy of the jungle.

A newly fallen tree also attracts local people scouring the forest for exotic orchids that might have been growing high in the canopy before the tree fell. These plants can bring a hefty price. The orchids are for sale in the local markets and collectors around the world support a legal and illegal orchid trade.

There are other dangers; toxins are common. Some palm trees commonly found near the ground on of the jungle have large poisonous spikes that will cause a nasty allergic response in the impaled hand unlucky enough to grab a trunk to avoid a fall. Large garishly colored caterpillars have poisonous spines. While these caterpillars are not aggressive, inadvertently brushing against one is not advised.

Paraponera ants that crawl on tree trunks are also called bullet ants because a bite from this inch-long ant feels like a bullet and causes pain for 24 hours. Their large mandibles cause what is said to be the most painful insect sting of all; the pain results from a potent neurotoxin. Initiation rights of some indigenous South American people entail repeated bites from these ants. It is difficult to imagine being stung 20 times without screaming, but this is what is reportedly what it takes to be a man in some cultures.

Poisonous snakes are also a concern, but are less common at higher elevations. It is possible that the bushmaster, Lachesis sp., the largest (up to 14 feet long) of the pit vipers, could be encountered up to 4000 feet elevation. The Fer-de-Lance, Bothrops asper, can be found on the ground or juveniles can be found in trees. Tree vipers also known as eyelash vipers, (two species at high elevations), hang from trees. Hog nosed vipers, tropical rattle snakes, and coral snakes all can be found in Panama. All these species are poisonous and bites from some can be fatal. It is always best to watch where you are stepping and move with care when walking in the jungle. This is not sandal country (but the next day we would see the exception) and boots, not flip flops, are advised. The dry season we were in, is also the time when the bushmasters are most likely to bask near Rio Maria, so we were particularly careful to watch for these vipers.

Of course, insect-borne diseases are also a concern, as they are in much of the tropics. Diseases found in Panama include malaria, chagas disease, dengue fever, yellow fever, and leishmaniesis. We killed an Assassin Bug in our hotel room, known to be a vector of chagas disease that can be fatal if left untreated. The usual precautions against insect bites and appropriate vaccinations at least decrease the worry. If you see an Assassin Bug in your room in Central America, kill it. These issues are not enough to keep many scientists and ecotourists away. The fabulous diversity and unique area are so attractive, and appropriate precautions minimize the chances of danger .

Leafcutter ants

2009-10-05T07:16:00.001-07:00

Near the upper edge of our research area, Alex pointed out an opening in the forest canopy above and the sunlight actually made it to the forest floor here where it shone on a massive dirt hill. The hill and the opening in the canopy were the work of leaf cutter ants; they had stripped the trees of their leaves above their huge colony. These ants forage into the vegetation, cutting off bits of leaves and bringing them back to their nests. It is said that the ants can defoliate a small tree in a single day. A web of ant trails spread out into the forest, each trail swarming with a line of ants coming or going. Some trials went up the trunks of the massive trees near the colony.

Large soldiers ran along the trials guarding the more numerous workers. Worker ants were carrying pieces of leaves as large as their own bodies. From a distance these trails looked like small streams of green leaves moving along toward the colony. The worker ants ran along the trails back inside the nest, left the leaves, and then scurried back the other way for more. The soldiers were always patrolling for predators that might eat the workers, including ants from other colonies.
Some smaller ants seemed to be hitching a ride on the backs of the ants that carry the leaves. My first thought is that these were the lazy ants. It turns out these are small soldiers that are the first line of defense against attack. They run along the trial unassisted but they also apparently ride on the back of the workers to fight off parasitic flies that try to lay their eggs on the ants’ heads.

Leafcutter ants cannot get nutrition from eating the leaves themselves, and tend gardens of fungi that grow upon the leaves taken into the chambers within the ant hill. Deep in the colony there is an even smaller bodied ant that tends rooms where the leaves are inoculated with the desired fungal food. The smallest bodied ants tend the fungi on the leaves, tend the larvae and attend to the queen.

The rooms below the jungle floor are the optimal humidity and temperature for the fungus. The ants weed other kinds of fungus and bacteria out and eat their preferred crop of fungus from their dark gardens. The ants also have bacteria in special glands that excrete antibiotics that keep the food fungi from being overgrown. Species of leaves that do not allow the proper fungi to grow are removed, and somehow the workers are signaled not to collect that species any more. If leaves that are growing the desired fungi are removed from the colony, the species of fungus that the ants like to eat is quickly overgrown by others. When a winged queen leaves to mate and start a new colony, she takes a bit if the fungus with her to start the new colony. The fungus would not compete without the ants, and the ants could not survive without the fungus, yet another example of coevolution.

The ants continually replenish their gardens with fresh leaf clippings for the fungi and remove the waste to the outside of the colony. The large dirt hill is made up of soil particles from the excavation of the colony and waste from the colony. Humans are not the only species that has had an “agricultural revolution”. When jungles are cut down the hills remain and can be a hazard for livestock. When cattle walk over the once active ant hill, it can collapse into the large area of caverns excavated below and a cow can become trapped. The ants damage crops and their colonies can damage roads.

These ants are common in the tropics and there are 41 species from two genera of ants, and they tend any of several species of fungi. Termites and ambrosia beetles are the only other insects known to tend fungi. This species is a fascinating result of evolution of social insects, with the adaptation to use fungi, the bacteria that helps maintain the fungi, and the six morphologies of ants all in the same species inhabiting the same colony (the smallest workers inside the nest, the slightly larger soldiers outside the nest, the still larger workers that collect the leaves, the largest soldiers, the queen, and during certain times males).

One enemy of the leaf cutters is the army ants that patrol the forest. These ants are predators that move in a continuous stream across the jungle floor. If you follow the trail of the army ants you will eventually come upon their nest. It is a bivouac that is a ball of ants as big as a watermelon suspended a few feet above the jungle floor. The queen is inside this seething ball of ants. The ants control the interior temperature of the ball by the rate they cycle to the inside. Follow the trail that leads from this ball of ants a mile or two through the jungle, and you will find the next bivouac with the next queen. These ants move through the forest, occasionally in swarms. The ants kill every insect that cannot escape and will even take smaller animals. Birds follow these army ants to snatch the insects the ants scare up.

It is fascinating to follow a trail of these ants. Where they come to a place that is difficult to cross, the ants grasp the one in front of them and make a chain of ants. Several of these chains side by side make a bridge for the remainder of the ants to cross over. If leaf cutter ants are the farmers, these are the raiders. Army ants are aptly named. They will overcome any other insect colony they encounter, or any animal that cannot get out of the way, regardless of size.

The Jungle

2009-09-28T13:42:00.000-07:00

I needed to sit and read a meter every 5 minutes or so, and was able to observed the stream more closely. While sitting on the stream bank, the diversity of types of tadpoles was unbelievable. I had been told how many species could be found in the sream, but the words did not convey the reality. Herpetology in general, and immature frogs in specific are not my areas of expertise, so I could not identify individual tadpole species. Actually, very few people can accurately identify most of the species in these streams from the tadpoles. In our group Edgardo and Scott were the specialists and the rest of us were just learning. Still, even to my unpracticed eye there was a clear variety present.

Some tadpoles were larger than my thumb and had very streamlined bodies. These used the suckers on their mouth to attach to rocks in faster waters. A large rock could have 10 or 20 of these. The scrape marks where these tadpoles had fed on the algae attached to the rock were apparent.

Chubby tadpoles with bodies that looked like slightly flattened spheres with a diameter wider than a quarter squiggled along the bottoms of the pools. These were not extremely fast and I caught one and its body felt like a bag of water. I released it and it skittered away. I wondered how such a slow large animal could exist without being preyed upon by snakes, lizards, and birds around the stream? Perhaps the fact that they were like a bag of water indicated that there was very little nutrition to be had in one of them, or maybe they were toxic. Given the impending extinctions, it is possible nobody will ever know the answer to the question.

Small tadpoles with bodies the sizes of orange seeds were wriggling around in shallow waters. I turned over some of the large wads of leaves on the stream bottom. Tadpoles with bright red blood vessels skittered away.

The open areas of the pool were perhaps 10 feet long, 10 feet wide and a half foot deep. Every one of these areas had herds of hundreds of small tadpoles, each the size of a pea, grazing on the microbes (algae, fungus, and bacteria) that lived attached to the sand and gravel. Any sudden movement would cause them to scatter for a while and hide, only to emerge a few minutes later and continue their incessant eating. Their only job in life was to gain enough energy to emerge from the stream, morph into an adult, mate, and produce more offspring.

Ecology is full of technical words, and the film of organism the tadpoles eat that is found on the bottom of the streams is called periphyton, a biofilm, or in more old fashioned terms, aufwuchs (one of my favorite words for some reason). In some strange way these tadpole flocks (there is no technical term for a group of them that I am aware of, maybe they school like fish) reminded me of the herds of bison that roam across the Kansas Prairie grazing the grass. Oh give me a home, where the tadpoles roam! Both the tadpoles and the bison are mainly eating machines and consume for most of their time. This constant eating is a requirement for any animal that eats relatively low quality food like grass or periphyton.

Time between writing down numbers offered me my first chance this trip to contemplate the riot of diversity that is a tropic rain forest. Evolution is occurring at breakneck speed relative to temperate systems. This has led to far more complex and diverse systems than occur in temperate habits. There are so many species of plants and animals that it is difficult to know how they interact, and fascinating to consider the linkages.

Plants struggle for light and nutrients. Water is not a problem here. Trees soar hundreds of feet upward into the canopy to intercept light. The trees have shallow roots that spread to intercept nutrients as soon as they reach the forest floor in the form of a fallen leaf, dissolved in a rain drop, or in animal excreta. The trunks of trees have wide buttresses (flared ribs spreading to the forest floor) to support their tall trunks. The buttresses give the jungle floor the feel of a green cathedral. The trunks and branches of all trees are covered with vines, mosses and other plants. Every square inch of available space is used.

The forest cuts the wind so flowers must be pollinated by birds, insects or bats. Each flower has its own tricks to lure the specific pollinator it needs and to exclude animals trying to steal the reward they offer to the type of pollinators they are trying to attract.

Exotic orchids offer odors as rewards that iridescent bees use to attract their mates. Each species of bee has its own cocktail of scents it harvests from different orchids, pollinating the flowers as they collect their scents. Humans were not the first species to discover the use of perfumes harvested from the surrounding to attract the opposite sex.

Some species of orchids are shaped to mimic bees. These flowers trick the male bees into attempted copulation, and deposit a pollen packet on to the presumably frustrated male. The bee goes on and if it makes the same mistake, it pollinates the next flower that fools it again (do they ever learn?).

This is not stark beauty like desert or tundra. It is diversity in your face with life evolved to use every nook and cranny. You cannot see far in the jungle, but there is lots to see right in front of you. There is something new for the observant biologist at every turn. If you sit still in one place in the jungle, the diversity will come to you. A mixed feeding flock of birds will eventually come foraging through the jungle. There are a half dozen species of birds in these flocks. Some eat bugs from the bottoms of leaves, others move up and down the trunks. Some of the species catch the insects that fly up when they are disturbed by the other birds. The birds receive benefits from feeding as a group; they are more likely to detect predators such as forest hawks, and their feeding habits complement each other.

Mixed feeding flocks are but one example of the co-evolution that is so common in the tropics. Species in this habitat are more likely than any other, with possible exception of coral reefs, to have evolved characteristic in response to the other species in the environment. Many species have complex adaptations to the others found in their environment.

The bull-horn acacia, Acacia cornigera, found on forest edges, is but one example. Ants protect trees and shrubs from grazers. If you hit the trunk of the shrub, the ants create a sharp smell which is the chemical (pheromone) that the ants use to signal each other that there is an invader. The ants swarm to attack any animal that tries to eat the tree. At night, the ants descend to clip back seedlings of other plants that might compete with the acacia. In return, the ants make their nest in large hollow thorns, and eat food bodies with fats and proteins, and nectar with carbohydrates produced by the plant. An acacia that has the ants removed is quickly consumed by the many herbivores found in the forest, including the ever-present leaf cutting ants. The ants and the acacias have evolved a tight cooperative (mutualistic) relationship in response to the benefits each can provide.

Many more examples of co-evolution exist. Toxic butterflies are brightly colored to advertise “don’t eat me”. Other species of butterflies have evolved color patterns that mimic the toxic butterflies so they are protected form predators. Every species of insect seems to have a specialized species of wasp that is parasitic upon it. This list of entangled interrelationships goes on and on and provides endless fascination for those interested in biology.

The First Experience with the Jungle Stream

2009-09-21T10:54:00.001-07:00

After each of us had walked up and down the stream, the lead researchers met up and settled on the experimental reach. This was a 300-yard long stretch of stream surrounded by jungle with no major side channels and a variety of pools and shallow areas (riffles) characteristic of the stream. Most streams naturally sort themselves into a series of pools and riffles through the natural processes of erosion. These processes also lead to the typical meanders or “S” shaped bends that characterize flowing waters.

We picked out sampling sites from the top down, each one a bit farther apart from the next, so we could sample correctly. Once the experimental area was set, we worked with Edgardo and the other Panamanian helpers and found the best way to get from each sampling site along the stream to the next. They then used their machetes (a standard item of hiking and work equipment for most rural Panamanians) to clear a rough path. We marked each of the sampling sites along the stream with fluorescent tape, and set up our equipment for the initial measurements.

The trail had its hazards. We could not step in the stream while the experiment was going on, so needed to have minimal crossings and placed logs and rocks to get across where we did need to go. The trail wound its way through a bit of sparse jungle, but the animal trials made false leads and it was easy to wander off the wrong part and we had to pay careful attention. I hoped we would not be caught on the trail after dark. After the sparse jungle the trail went across a marsh, which we filled with logs, but they kept sinking as we would walk across them and the crossing was precarious at best. Right on the edge was a palm tree, and it was natural to grab the tree if you slipped into the mud off the logs. Unfortunately the tree had huge spines and the spines had an irritating substance on them. More than one of us grabbed the tree by mistake and was impaled. It is the kind of mistake you only make once; unfortunately I made that mistake several times.

The trail went next to the stream in parts and up and down steep-slippery sections, and included some logs. At the top of the trial was a large rock bar where we were setting up our system to add the chemicals to the stream. Just above this part there was a branch in the stream and the jungle was a bit more open, so large shafts of sunlight played through the branches onto the stream. This was a beautiful spot where we could see a slope too steep to climb rising between the two stream branches and huge trees towering hundreds of feet above our heads up the slope. Boulders the size of shuttle busses had fallen off the sides of the steep slope and lodged in the stream channel, and massive tree trunks had recently fallen across the stream above taking out many others on their way down. Above our top location, the stream was a jumbled mass, and it was very difficult to get through to the stream above, but the effect was wonderful.

Since we were going to use an inert chemical tracer to follow how nitrogen moved into the animals in the stream, samples needed to be collected to establish a baseline, and also to establish our basic protocols of measurement. Our group split into smaller groups.

One group collected the leaves and algae in the stream that form the base food source for all the animals in the stream. These samples were collected from a known area so we could estimate the relative amount of each that were present in the stream. At previous streams where the frogs had gone extinct the algae had exploded, so we wanted to catch that with detailed measurement. Even in these shaded streams there was enough light to allow some algae to grow.

Other groups collected the tadpoles, insect larvae, crabs, fishes and shrimps that populate the stream. These collections required careful netting and counting of individuals. We needed to be absolutely certain to quantify the existing conditions, because we knew of the changes that were coming and there was no going back. All these collections also needed to be made with much caution to minimize the disturbance of the stream channel so as not to interfere with our measurements in the following days.

Simultaneously, Bob, Alex, Matt and I set about making additional basic preliminary measurements required to start the experiments. Measurements were made with chemical sensors (measuring oxygen gas dissolved in the stream water, temperature, and other important water quality parameters). We started electrodes that would record the chemical conditions and temperature in the stream for the entire duration of the experiment. We took chemical samples required to calculate how to start the experiment the next day.

We started other measurements to determine how the stream responded to pulses of nitrogen and how pulses of tracers we released at the top moved down the stream. The results from these releases allowed us to account for how quickly the water moved through the system, and how much water was flowing. We took background samples of water to measure nitrogen so we could calculate how much nitrogen tracer to add and for how long. All these water samples would be analyzed later that same evening. Bob had a very nice approach where we could add the chemicals streamside and the samples would incubate and be ready to analyze that evening. Length, width and depth of every few feet of stream over the 300 yards or more of the experimental reach needed to be recorded.

Some time was spent just sitting on the stream bank and waiting between measurements, occasionally writing down numbers in the field book. Field research can be a curious mix of rapid, hard, physical work, then intense calculation and concentration, interspersed with waiting and observing.

Rio Maria and the jungle

2009-09-09T14:05:00.000-07:00

Our research group had a central goal of finding out what would happen to the high elevation jungle streams after the tadpoles disappeared, so it was necessary to measure everything we could about the biology of the streams while the frogs and tadpoles were still there. Part of the process of scientific understanding is detailed observation, and we needed to be sharp and pick out the most important details to measure in this stream, to capture the true way the system worked. The baseline conditions of how the organisms influenced their environment, which organisms were there, and how they interacted all needed to be measured. We had limited time on this trip and had to make the best use of that time. This is the scientific way to talk about the environment we were about to enter, but there is more to biology than just measuring things.

It was hot in the sun out with the trucks as we fussed around with our gear. We got all the stuff we needed for our first set of measurements and started loaded up for our first trip into the jungle. The edges of the road were overgrown with a tangle of grass and bushes, as is always the case in the tropics; a road cut lets in valuable light and the plants fight for a toehold in this newly opened habitat. We needed to force our way through this on a tiny trail that had been hacked out by machete a few days before, and there were holes, fallen logs, and slippery muddy bits that needed to be negotiated with heavy loads of equipment. Our gum-boots did not making the footing easier, but they probably would protect from the fangs of a snake, and did keep our feet dry. Of course, we needed to also keep an eye out for sunning fer-de-lance, the extremely toxic snake that frequented the area.

As I entered the damp shade of the dense jungle near the stream, the temperature became more pleasant. This was another world. Rio Maria was a beautiful stream as it flowed through the jungle. A few shafts of sunlight found their way through the riot of tangled green to dance on the surface of the stream and dapple the rocks at the bottom of the clear waters.

Clear-winged butterflies flitted through the forest. These butterflies are fantastic as they have a rim of color around one or two almost completely clear wings. The oval-winged butterflies appear to fly slowly, but prior experience with a butterfly net convinced me that the clear wings make it difficult to see them and judge what direction they are going to fly. Or maybe I just suck at catching flying insects. Clear wings are probably a good predator defense, at least against inexperienced collectors.

Garish red flowers (hibiscus, passion flowers) dangled from overhanging vines or grew from the jungle floor. The vegetation is not extremely dense at the forest floor because so little light reaches it. Mosses covered most surfaces, including the tree trunks, fallen logs, older leaves, and the edges of the rocks near the streams. Tropical rainforest is part of what lured me back to Central America, and reality exceeded memory.
There were frog calls from hundreds of feet above in the tree canopy, down in the low vegetation, near the stream, and from the hillsides that surrounded us. The sound of chirping frogs constantly came from all directions. The calls blended with the insect sounds (cicadas and others) and bird calls.

Our first task was to decide which section of the stream would serve as the research site, so we set off through the jungle upstream to have a look. With each step in the forest, small brown frogs jumped out from under our feet. We had to be careful not to step on them. At the stream crossing (chosen with care so as to not disturb the bottom of the stream for our experiment) the pool had hundreds of small tadpoles swarming along the bottom.

I have spent quite a bit of time studying aquatic systems and the only time I have ever seen so many frogs and tadpoles at these densities was in the quaking bogs surrounding small lakes high in the Oregon Cascades in the 1980’s. These bogs form at the upstream end of lakes and have floating vegetation mats and deep water holes that the unwary will fall into. The conditions, once the snow melts, are perfect for breeding frogs, and they are everywhere there. My mind drifted back to Oregon, and then snapped into focus on the jungle frogs at hand.

Water in the stream gurgled between the rocks, rocks rounded by the many floods over the centuries rolling them along the stream channel and grinding them to smoothness. First they were eroded by the weather until were free from the volcanic hillsides above, then they fell and washed down the outer slopes of the crater, and eventually they would be ground by the energy of the water scraping them against other rocks to end up as grains of sand on the ocean beaches tens of miles away.

Occasionally parrots would make a racket in the distance, a toucan would fly high overhead, or a blue butterfly with a wingspread wider than my head (Morpho) would glide past. I found myself looking for monkeys and sloths, but found none.

From El Valle to Rio Maria

2009-08-31T09:05:00.000-07:00

Having gotten settled into the hotel with plans made, lists created, and some materials packed and organized, the group piled back into the vehicles and headed into town for dinner. The small restaurant we went to on the main street was also a hotel that catered to young tourists. It was open to the front and to the side overlooking a lush garden. The lone server eventually showed up at our table (it was not exactly clear what took her so long as there was nobody else in the restaurant, but that is Panamanian time) and we ordered some drinks and dinner.

Panamanian food is unique; Americans might assume it is spicy, like Mexican food, but mostly it is not. As with all Central American food, rice and black beans are common. However, fried green plantains (patacones) are often served as a starch instead. Other common starches included potatoes and tortillas. The tortillas are corn patties that are substantially thicker than those common in Mexico. They are fried in oil and are very flavorful. There are a variety of meat dishes and beef is common. Chicken is served in several more diverse dishes. One of my favorites was chicken with garlic (pollo al ajillo). While most Panamanian food is not spicy, this dish is loaded with garlic, about a head of garlic per plate. Those who want chili head in their food can use the habanero pepper sauce that is regularly on the table. The food in the restaurant, while simple, was delicious.

After dinner we returned to the hotel and started going through lists of experimental equipment required for the next day. It took an hour or so to get ready and go over plans with Piet asking questions. We needed to charge up the batteries for field gear and make sure we did not forget anything because the 1.5 hour drive back to the hotel from the field site would preclude getting all our field work done if we had to return for additional equipment. After a rum nightcap, we headed to bed with plans to wake at sunrise.

It was an early start with a quick breakfast of fruit and cereal. Coffee drinkers had theirs, and I had a warm diet coke that I had picked up from the grocery store the day before, yum. We finally loaded the gear into the four wheel drive trucks and hit the road. The trucks are really well set up for the research. They are diesel, and have quite powerful engines, extended cabs, and take a lickin’ and keep on tickin’.

There was actually a road going up along the crater walls through that looked like cliffs from the hotel. The dirt road to the research site wound its way up through the inside of the crater walls and eventually crossed the lip of the crater; the entire road was extremely steep and rough.
As we worked our way up the steep valley leading out of the volcano it became evident that a number of people lived in the valley. A few miles up the road there was a small store and a school. A small soccer field clung to the edge of the hill. A couple times a day, a small bus came along. Most of the small farms up the side of the hill used foot or pack animals to carry materials in and out to the edge of the road, some all the way down to El Valle. As we wound our way up the side of the volcano the jungle became more predominant and the farms farther apart.

Eventually we reached the steepest hill on our trip. At this point the trucks had to be shifted into low 4-wheel drive, and we needed to get a running start at the hill. The trucks are old-style 4-wheel drive and we got out and locked the front hubs before starting. Some of the more nervous (experienced?) passengers got out and started walking up the worst of the hill on foot. This road went straight up the side of the mountain and had deep ruts from winter rains and other 4-wheelers. The vehicles bounced up and down and rocks shot out behind as the wheels spun. One of the drivers did not start fast enough and had to back all the way down and start again. If driving up such a steep hill was difficult, you can imagine the danger of backing down.
We finally got to the top of the hill and wound our way over the rim of the volcanic crater. When gaps in the jungle allowed, we could see all the way down to the coast, and other hills and mountains in the distance. The view was spectacular. The jungle here is very thick and lush. It is a rain forest that catches moisture from the clouds that roll in from the ocean, and the trees are covered with moss, lichens, and epiphytes including orchids. This dense green vegetation occasionally opened up to frame views of a thousand foot high pinnacle created by old cinder cones (Picachao Mountain) on the edges of the volcano. Near the top there were several hundred feet of sheer vertical cliff face of rock, where the volcanic deposits that formed the ancient eroding cone were exposed, otherwise the jungle clung to the cliffs and hills. Flocks of parrots flew across in the distance. A small lake was nestled into the bottom of the pinnacle, this lake had formed when a secondary explosion opened a crater that subsequently filled with water.

After working our way a few miles down the outside flank of the volcano we started to catch glimpses of the valley for the Rio Maria, our research stream. The stream originates high in the steep outer walls of the ancient volcanic crater, as the rivulets combine it forms a large valley that winds its way down the mountain across the coastal plains to the ocean, 20 miles or so away. We parked our trucks near the edge of the bridge and we got out to look at the stream. The sound of calling frogs met us immediately. There were two golden frogs on the stream bank across from where we parked, and we started taking some pictures, but we needed to get our first experiments started so we did not spend too much time looking around.

In the volcano

2009-08-24T12:57:00.000-07:00

We pulled off the road at an overlook to take in the city of El Valle. The view was breathtaking. The town is nestled at the bottom of a huge volcanic crater with the rims of the old volcano rising circling above it. The rim of the volcano is so steep it forms almost vertical walls around ¾ of the city.

About a million years ago, the mountain that was El Valle volcano experienced a massive and cataclysmic explosion. The explosion left a 3½ mile wide crater and walls over 600 feet high. After the explosion the crater filled with water and contained a lake. The sediments and dead animals and plants in the lake waters settled over many years creating a flat bottom. Eventually a side of the crater washed out leaving the flat bottom of the lake that became a rich soil. This verdant land became the site of the town of El Valle and the cropland that surrounds the town. The steep walls of the crater are now draped with jungle so the area has the feel of a hidden tropical paradise, a Central American Shangri-La.

The high altitude leads to perpetual spring time. In the tropics, flowers are always blooming. It is a beautiful area and there is no doubt why people want to own houses on the slopes of the volcano and why many Panamanian tourists and international visitors vacation in El Valle.
Small houses and fields cling to the slopes of the steep walls of the volcano about 1/3 of the way up the sides. Eventually, the pitch gets so steep that the land cannot be lived on or worked and it gives way to jungle. When the slope is steep enough there are sheer rock faces that even the jungle cannot cling to.

The steepness is why there is still any wildness left in the area. Crops are scratched out of hillsides that would be considered un-farmable in the US because mechanized agriculture cannot be used, but the hills eventually are too steep for manual agriculture. The farms clinging to the hillsides reminded me of Switzerland where crops or grazing pastures are on slopes so steep a loss of footing could lead to a fatal tumble. It was obvious that the dirt itself was just clinging to the volcano sides from the numerous scars of landslides on the slopes around the valley.
The town looked very inviting because of the green productive fields and then the steep walls surrounding El Valle; we looked forward to getting down to our home base. Edgardo pointed out a large white hotel across the valley that was to be our headquarters for the next 9 days. We got back into the trucks and wound our way down the steep mountain road toward it.

When we drove up to the Hotel Campestre, it was clear that it had once been an opulent inn. The expansive grounds appeared well designed, with a circular fountain in front of a large central building. The hotel had a backdrop of a nearly vertical vine-draped wall of the volcano. Spreading to the side of a large main lobby and restaurant area, there were a couple of white two-story wings of the building housing 20 rooms each. In front of the hotel and a bit off to the side, we saw what was once a large swimming pool. Along one end of the pool there were smaller stepping-stone pools with fountains and waterfalls connecting each pool eventually cascading into the main swimming pool. Just past the pool was what appeared to be a caretakers quarters.

Upon closer inspection, the pool was filled with sediment, vegetation and insects. For biologists, the decay of the pool offered an opportunity, and while Matt and Edgardo checked us in, the rest of us tried to identify its inhabitants.

The most impressive animal in the pool was the large dragon fly larvae. These larvae are fearsome predators with a flip-spring jaw with a small hook on the end that extends in a millisecond to grab unsuspecting small aquatic insects and even fish. We also saw our first tadpoles here. There were, unfortunately, also many mosquito larvae, so the dragon fly larvae were not keeping up with their job, and I was wishing my DEET was not in my lost luggage.

The main entrance of the hotel had large wood timbers for support and overhead. We walked through the lobby to get our keys, and there was an aquarium with a bright yellow and dark brown splotched frog. This was the famous Panamanian golden frog (Atelopus zeteki), about 2-3 inches long. This poor fellow did not look well and Matt remarked that they probably purchased a new frog caught by locals from the plentiful supply in the nearby jungle every few weeks and didn’t worrying about feeding it.

The Panamanian golden frog is considered lucky. Legend has it that indigenous people in the region traveled to El Valle to catch the frogs. Some considered it a symbol of virility and prosperity. The frog adorns lottery tickets in Panama and the species is an icon in a land with many, many attractive species. This was one of the species that would disappear from the wild when the disease swept through the region.
We got our keys and I helped the others carry their gear to the rooms, and our equipment to the lab. Edgardo, his girlfriend Heidi Ross, Piet Verburg, and Scott Connelly, were living in the lab-house combination off the edge of the hotel that initially appeared to be caretakers housing. This house had been a duplex and each side had a large kitchen in front and several back bedrooms. One side had been left for housing and the other converted to use as a lab and storage area. The large front room on one side that had been converted into a laboratory was stacked with equipment and the small amount of table space was given over to sample processing and analysis.

As we approached the lab/ house, a small whitish dog came out to greet us. As with most Central American dogs, she was not well kept. She was also pregnant. Since she got food, she kept returning to visit us and bark at any strangers who happened by. She was a nice affectionate dog, but I was not sure that petting her was worth the risk of fleas. The dog, however, eventually won me over.

This is where I had the pleasure to first meet Heidi Ross, who was hired to work on the project as a technician. She initially came to Panama with the Peace Corps to El Cope. This was an earlier site for the frog project as well. El Cope is now little use for frog work because the disease already swept through there. She was interested in the frog work that was occurring before the disease came and volunteered to work on the project. Eventually, after her stint in the Peace Corps was done, she was hired and ended up getting together with Edgardo. Heidi wears her long curly hair in a ponytail and has nice green eyes. She was always around Edgardo, who is outgoing and gets most of the attention. Heidi is quiet but occasionally throws shocking off-color jokes into conversation. She is an excellent worker, never complains in harsh field conditions, and loves working with the frogs.

Piet Verburg was in the lab building and helped us get settled. Piet was the hired gun (we referred to him as Pistol Pete) on the project and had been living in the lab/bunkhouse building and starting to work on the research sites. Pete was on a postdoctoral appointment and did not have the numerous responsibilities that academic faculty members at universities have. Postdoctoral appointments are the positions many academic researchers must take before they get a permanent faculty position. These positions pay marginally better than graduate positions, but have no permanence. Often the postdocs do all the actual work on a project because they are trained and research is their only goal. It generally is a chance of a lifetime to totally immerse oneself into research.

Piet was born and raised in the Netherlands. He was hired for his top-notch research skills and expertise, and willingness to travel the world to do aquatic research. Piet did his doctoral research on Lake Tanganyika in Africa, a lake with hundreds of species of tropical fishes. He is a wiry athletic individual, with tight-cropped hair and wire-rimmed glasses. He moves perpetually and very extroverted. He will get up early and run 6 miles, do physical work all day, and then smoke and drink all night long. He persistently asks questions and loves to challenge the status quo and established scientific knowledge.

Scott Connelley was the third new person I met then. He is a graduate student who was studying the frogs for his dissertation. He is a short, dark-haired individual with a well trimmed beard and dark, quick bright eyes. He is energetic, quick witted and full of stories and dirty jokes to pass the time. Scott is also an excellent photographer who has been documenting the frogs in the wild before they go extinct. He regularly gives talks on loss of tropical diversity and is dedicated to conservation.

We set up our gear in the lab, and started to discuss our research plans. Piet asked questions and questions about our answers. We knew time was limited and needed to get to the stream, so we tried to be as direct in our answers as possible. We needed to get a fast start on the study the next morning to start our preliminary measurements. The experiments were going to be detailed and required substantial advance preperation. Some of the analyses we could do back in the US, but others required knowledge of the actual stream. So this time was also taken to get information from Scott, Piet, Heidi and Edgardo.

Understanding the effects of the frog losses required making sophisticated measurements of how the stream ecosystems work in the most fundamental sense. How nitrogen and carbon (fundamental chemicals found in all living organisms) flow through the plants and animals found in the streams is a essential characteristic of how these systems function. Our stable isotope method used forms of nitrogen and carbon that differ slightly from most of those elements found in our natural environment. We were going to take advantage of that fact to trace the fate of these compounds that are central to all biology as we know it, and specifically to the biology of the stream we were planning to characterize.

This type of research is an example of new, high-tech approaches that are available to environmental scientists. The nitrogen is a special form that has one more neutron in the nucleus, so it is a slight bit heavier than the more abundant form that has 7 neutrons and 7 protons (just 1/14th heavier). As far as the plants and animals are concerned, the tracer form of nitrogen with 8 neutrons is identical to the more abundant form with 7 neutrons, but science can tell the difference.

The samples that could have our tracer in them can be taken in the field and dried and ground up in the lab. A tiny bit, about the size of a head of a pin, is put into the mass spectrometer. The mass spectrometer burns up the sample and converts the nitrogen to single charged atoms. Inside the machine there is a series of magnets that accelerates the charged atoms into a stream of particles that are shot in a line through a tiny hole in another magnetic field. The field bends the charged atoms. Heavier atoms bend less than lighter ones, just like it is more difficult to make a tight turn with a large truck speeding around a corner than it is a sports car. The machine has a detector that can sense the two particle streams and indicate how much of the heavier atom there is. The numbers from the machine can be used to tell the relative amount of the tracer nitrogen there was in the sample.

We planned to add a pulse of these non-toxic tracer compounds and collect numerous samples during and after the pulse to characterize how the nitrogen was used in the environment. Samples were to be returned to the US where mass spectrometry could be used to analyze the samples and the results would eventually be used to calculate how quickly the materials moved into the plants, animals, microbes, and various chemical pools in the water.

The isotope and our time were both quite costly, so organization was absolutely necessary, and made more challenging by the makeshift conditions at the lab and even more demanding conditions in the field. We hoped it would not rain, and given it was the dry season, we probably had a 50% chance of dry weather. A flood could spell disaster for our project. The high walls of the volcano often caused the clouds to drop their moisture even in the “dry season”. Here, dry was relative. In addition, the steep walls lead to very rapid run off when it does rain, increasing the probability of flooding. The experiment was a one shot deal. We would not have time to redo the experiment if it was halted by a flood and it was unlikely that we would be able to get all the researchers back down to try do the experiment again. Plus, we did not know exactly when the frogs would start dying, and we needed measurements from before the die off.

From Panama City to El Valle

2009-08-17T09:11:00.001-07:00

As we drove through downtown Panama City on our way to the mountains, Edgardo pointed out a barrio. The barrio was a jumble of unpainted high-rise apartments; unit was obviously inhabited by many people. The rooms all had either broken out windows or never had any installed and laundry was hung across most balconies along with lot of other unidentifiable stuff. The buildings were run down, dirty, had stained walls and crumbling. Edgardo told us that any US citizen who entered the barrio would probably not leave alive.

This was where Manuel Noriega had his headquarters; he had used it as a human shield. This decision, and the US invasion to unseat Noriega led to death and destruction. Noriega was the dictator of Panama from 1983 to 1989. He initially was on the payroll of the US Central Intelligence Agency because of his opposition of socialist governments in Central America and help controlling drug trafficking. For a while the CIA, turned a blind eye to his association with drug lords (Noriega was playing both sides of the fence here), weapons runners and the corruption in his government.

The 1989 election was rigged by Noriega, and former US president Jimmy Carter denounced the election as fraudulent. The potential loss of transport, including oil, through the Panama Canal was probably too great a financial risk to the US. US army personnel were harassed by the Panamanian military and one off duty US officer was shot. The situation escalated and in 1989 George H. W. Bush ordered the US to attack Panama to capture Noriega. Protection of the Panama Canal, protection of US citizens, restoration of democracy and human rights, and control of the drug trade were cited as the reasons for the invasion.

The US sent in over 50,000 troops and 300 aircraft. The attacks on the barrio caused as many as 5,000 Panamanian civilians to be killed; most died in a fire in the barrio around Noriega’s headquarters. There is still hatred there toward the US; emblematic of the darker side of the love-hate relationship Panama has with the US. The relationship has been long, with its origins in the US cutting the country in half by building the Panama Canal starting in the early 1900’s.

When I had visited Panama City in 1977, the canal was still under United States’ jurisdiction. Tensions existed then in the form of resentment toward the wealthy country that ran the canal in the midst of deep poverty. I will never forget the image of a suburban landscape, where the US military and canal zone personnel lived, surrounded by Panama City. The neighborhood was indistinguishable from the one I grew up in, except for the tropical flowers and palm trees in the gardens. Large mowed lawns being sprinkled, split-level houses, multi-car garages, and large cars were everywhere. Across a low wall and a four lane street was a slum with tar paper shacks and a burned-out apartment building without outer walls where many people lived. Large families lived in one room with no running water. The separation between rich and poor in the US was much better hidden.

There are large disparities between rich and poor in Latin America, but many of the rich build their houses behind walls. The walls often have broken glass embedded along the top or barbed wire to keep intruders out. The walls preclude a casual assessment of the amount of wealth from outside. The other places I had visited in the US, Canada, and Europe did not have the same degree of stark contrast clearly visible from the street between the poor and those with comfortable lives. The disparity was intense, and it highlighted a sharp inequality between my sheltered and privileged middleclass upbringing and the way much of the rest of the world lives.

In my 1977 trip, I felt the tension in the Canal Zone because the Panamanian military was a good bit more menacing than what I had experienced in Costa Rica. The civil service soldiers in Costa Rica were friendlier than the Denver police I had grown up with. The Panamanian military had machine guns slung over their shoulders, tightly cropped hair, and vacant looks in their eyes that I imagined were the looks of stone cold killers. I did not linger in front of them long enough to find out.

These thoughts ran through my mind as we passed the barrio where Noriega had his headquarters and made our way through Panama City west to El Valle. To go west from the city, you must cross the canal. We left the city via the Centennial Bridge over the Panama Canal. The bridge is almost a mile long and over 250 feet high. Large ocean-going ships pass under the bridge with no problem. As we crossed the bridge, I could see tanker ships lined up into the distance waiting to get into the canal. Another line of tankers chugged away into the Pacific Ocean having successfully crossed the isthmus from the Atlantic side. This is one of the great centers of commerce in the world.

The Panama Canal was and continues to be an enormous undertaking. Almost 28,000 workers died during its construction begun in the 1800s by the French and finally completed by the US. Now more than 200 million tons of cargo pass through it each year. The average ship pays $54,000 to go through the canal, resulting in almost $800 million in revenue a year. The US controlled the canal in Panama from when it was completed in 1914 until 2000.

The canal had its positive effects for the study of ecology. The Canal used dams to create large lakes in the center of Panama, and one of these lakes isolated Barro Colorado Island. Early in the history of the Panama Canal this island was protected as a biological reserve, one of the first in the New World.

Since then the Smithsonian has managed the site and it is one of the top tropical ecological research areas in the world. I visited this site in the 1970’s and this was one reason for my choice of career. The research station had a canopy crane so you could get up into the tops of the tropical trees and see the birds and butterflies fly through the canopy. This vantage point really makes it clear that tropical jungles have considerable habitat where people have difficulty reaching; the hundreds of feet of tree canopy is where most of the ecological action occurs. This also was the first place I saw lizards that could run across the surface of the water (JC lizards), live sloths, and many other tropical plants and animals. The long research record at the island makes it an extremely valuable ecological site, and with each year of data the Barro Colorado becomes more important.

The United States had sovereignty of this land that cleaved Panama; an obvious source of tensions between Panama and the US. Eventually the canal was returned to the Panamanians. Edgardo told me that many Panamanian citizens are not so certain that Panama should have taken the tremendous maintenance demand and responsibility for this vital passage from the US. However, the importance of the Panama canal may become a moot point with global warming; summer in North America now leads to an open Northwest Passage through the Arctic Ocean. In the future, with melting of the Arctic Ice cap, the passage could remain open for a large part of the year and take much of the traffic away from the canal. Given that Panamanians know that the US released much of the greenhouse gas that is causing this melting, they may have another reason to resent us. Still, the canal for now is central to the identity and economy of the country.

We made our way west on the Pan-American highway on a beautiful day, leaving Panama City behind, heading toward the high altitude jungles that were our destination. We had to drive west because although the Pan-American Highway is mostly a north/south highway, this part of the highway leads east/west. Because of the curve of Central America and where Panama is located, the country spreads from east to west.
The Pan-American Highway becomes less of a highway in the North American sense as you move away from Panama City. It is certainly not limited access. Pedestrians, bicycles, mules, wagons and other modes of transport move along edges in more rural areas. Small shops have their parking lots right next to the road, and access is not limited. This is a very busy central artery to the country full of trucks and cars.

After an hour or so of driving we stopped at to get fresh empanadas (hot cheese turnovers) and other refreshments. The cheese and empanada shop where we stopped smelled fantastic as any active bakery does. In most of the US, local bakeries are rare, and our lives are less enjoyable as a result. Furthermore, this was an excellent cheese shop, most places in
Central America carry only a few types of simple bland cheese, but this shop was replete with a variety of locally made cheeses. Having native Panamanians as members of our scientific team to educate us on regional delicacies definitely had its benefits.

Our next stop was to secure breakfast and lunch provisions from the grocery store for the next 9 days. This store was emblematic of the US influence on Panama. The landscaped parking lot and exterior of the store in a strip-mall setting would be indistinguishable from thousands of strip-malls in the US. The grocery did not have the variety of items available in North American supermarkets, but it was obviously modeled after the large grocery stores in the US. We purchased food that would keep for a few weeks in the tropical heat (tins of meat, sardines, clams), crackers, breakfast foods, snacks (chips and cookies), and beverages.

This trip marked the beginning of my appreciation for Latin American rums. We each purchased a couple of bottles of rum of different ages (5 to 25 years old). It turns out that Matt chose the store not only for the food, but probably more importantly, for the rum selection. There are many varieties available, and as I would find out, almost all but the very cheapest ones are excellent. Of course we also grabbed some cases of beer, soda, bottled water, and cans of Pina Guava (pineapple and guava juice) and limes (for breakfast or to mix with the rum in the evening). We crammed our provisions into the already full trucks and continued to head toward El Valle de Antón.

We first could see the location of El Valle as a distant peak rising above the hazy tropical plains of Panama. The peak is one of numerous volcanic cones that dot Central America and one of three large inactive volcanic cones in Panama. As we wound our way up the slopes the air became cooler, and our trip became more pleasant.

Small shacks and rudimentary concrete roadside dance halls blaring distorted Latin music and hip hop through large speakers lined the road side. This area at the bottom of the volcano was obviously agricultural and not wealthy. The vegetation was dry and sparse, but slowly began to switch to wetter, greener trees as we moved up in elevation. Simultaneously, the houses began to give way to more expensive haciendas.
This region has a history of one where wealthy Panamanians build second houses because the cool weather offers an escape from the heat of Panama City. Now it is a magnate for wealthy from all over the world including retiring US and European couples. As we found out, this movement toward large second homes is not always so good for the native flora and fauna. Eventually we made our way over the upper lip of the volcano and started our descent into the ancient crater, there we caught our first glance of El Valle.

Into Panama City

2009-08-10T09:55:00.000-07:00

We loaded our gear into a couple of pick-up trucks and station wagons and left the airport. It is always strange driving into a new city, but doing so at night is more disorienting. Doing it jet-lagged, and in a different country adds to the surreal nature of arrival. We could see billboards advertising unfamiliar products next to those typical of the United States. It is difficult to avoid the economic tentacles of the United States; McDonalds, Kentucky Fried Chicken and Johnny Walker are everywhere.

The dark estuaries of the bay of Panama along the highway reeked of the sulfide and decay of marine mud. Most people do not like this odor, but it made me wonder what organisms were out there, in particular if there was any good algae. The tide was out, and across long black mud flats, the waters of the bay reflected the lights of large cargo ships. They line up to wait for the chance to go through the Panama Canal. The lights and skyscrapers of downtown Panama City were in front of us.

We entered the traffic of Panama City close to midnight. As in any large city, there was still considerable activity despite the late hour when we drove into town. The hubbub of crowded streets had a definite Central American flavor. There were cabs and busses painted with brightly colored murals of various religious and movie themes plying the streets. The cars and trucks were from all over the world. People had kept some very old vehicles alive and they belched exhaust as they noisily drove down the streets. We were entwined in hectic traffic; even though there were many older vehicles, there were some very expensive luxury cars as well. This provided the first taste of the juxtaposition of wealth and poverty of Central America.

Hotel Acapulco was tucked into a block of commerce and most businesses in the area had a parking lot surrounded by barbed wire. We pulled in, parked and carried our luggage (at least everybody else’s luggage) into our rooms, a guard watched over the lot and the front of the hotel. The gate was locked to protect the vehicles as we drug our luggage into the hotel.

What followed was the usual hour of haggling with the front desk. The uncertainty ensued because of lost reservations and changing “hotel policies”. Even with several of our party fluent in Spanish, the rooms took a long while to sort out. The extended discussion at the hotel desk always happens; nothing is simple in Central America. The rooms were not new, but they were not particularly dirty. Once we settled in, it was time to get something to eat. I will never understand why it makes me tired and hungry to sit around in airplanes, airports and taxis doing nothing all day.

Our hotel was across the street from a large casino and adjoined a 24-hour restaurant that catered to the late-night crowd associated with this active part of downtown. We took over several outside tables and ordered Cerveca Panamá (obviously a local beer). We ordered several types of ceviche (shrimp and corvina (a white sea bass) marinated with lime juice, cilantro, onions, and chilies). Ceviche is traditionally served with saltine crackers. We ordered streamed clams, some cooked octopus and more beer. Seafood is good in a port town, and we were not about to pass up the chance to have the real deal. Particularly me, coming from winter in a small town in the Midwest, appreciated it. Fresh clams are generally not on the menu back home.

Of particular interest to our group was a carousel inside a closed case that held pies. It was not that the pies looked so great, but the velocity at which the stacked lazy susan was rotating was astonishing. It must have been set on high, and we, being science nerds, referred to it as the “pie centrifuge”. At the time it seemed hilarious, but we were probably delirious from travel and beer. The food was excellent and it was entertaining to watch the street walkers and other characters of the city passing by.

After a bit we went up to our rooms, bleary eyed and travel worn. I brushed my teeth with my finger and water, splashed water on my face, hung my clothes to air out and got in bed. Matt had set his hair brush by the sink. This is a brush he has had since middle school and it is absolutely disgusting. The “brush” is decades old and just held together by the hair bonded to the remaining bristles. I am convinced he brings it when we room together just to bug me. The sound of the city below continued to seep in through the barred windows as I drifted to sleep with the gentle breeze and whirring sound of an overhead fan.

In the morning Matt and the others left to take care of business at the Smithsonian Tropical Research Institute, not far away in Panama City. Right after lunch we were to leave for El Valle, the jungle and the frogs, so I had till noon to get a few things. The normal travel precautions (no valuables left in the room, passport and extra cash in a hidden pocket) were taken before I left the room to replace essentials that were in my luggage.

I walked down the street toward a department store. Rapid fire Spanish surrounded me and I purchased an orange from a vendor for breakfast. Conveniently, the Panamanian dollar is tied to the US dollar and there is no need to exchange currency.

I found the department store and purchased the basics. On my way back I saw what turned out to be my favorite hand-painted city bus, it had a Harry Potter theme, but made Harry look deranged. Matt and the gang returned and we had a quick lunch in front of the pie centrifuge, loaded the vehicles and left for the El Valle.

Flying to Panama

2009-08-03T10:34:00.000-07:00

Despite the facets of traveling overseas to accomplish research, we were committed to getting to the site before the frog extinction wave hit, making the necessary measurements, and going back again after the wave had passed through. Planning such a trip is not an easy task. As with all trips to developing countries in the tropics, immunizations and travel precautions were required. Packing for an extended trip is always difficult. Adding the requirement of accomplishing cutting edge research exponentially increases the difficulty.

We needed to plan the experiments in exact detail, while accounting for the inevitable contingencies that arise in the field when plans meet reality. I have driven three hours to a research site, only to turn around 15 minutes after arriving for having forgot an essential piece of equipment. The prior Panama research team had a pump break down and a student sat next to the stream for hours making exact additions of test solutions. Best laid plans go awry, which could spell disaster in places so far removed from sources of scientific equipment and materials. Requirements for air travel (chemicals cannot be packed in suitcases so must be ordered by an institution in Panama) compound the situation. Travel restrictions following terrorist attacks now preclude carrying significant amounts of fluids onboard, yet solvents and chemicals that cause concern are required for our research.

Not only does is planning required to get research equipment overseas, but also arrangements must be made so samples can be brought back. It is difficult to keep a significant amount of sample material frozen during international travel. Only very small quantities of dry ice are allowed on airplanes and many samples are unusable if they thaw out. Also, permits are required to remove biological materials from other countries and transport them into the United States. Permits necessitate a lot of advanced paperwork, planning, and waiting.

Restrictions on bringing biological materials back into the States are reasonable; incalculable economic and ecological damage could result if the wrong pest was released into the US. It has happened before, and will happen again. Take for example kudzu, water milfoil, purple loosestrife, zebra mussels, and many other nuisance species introduced into the states. People try to smuggle all kinds of animals and plants across international borders. Restrictions are also in place to stop trade in endangered species, living or dead.

Pieces of equipment absolutely essential for successful completion of experiments must be carried onto planes. This expensive equipment could be lost in transit or damaged by inattentive baggage handlers. In simpler times carrying undefined, but complex electronic equipment onto airplanes was not problematic. Our $8000 oxygen/ temperature probes with data loggers are long, bazooka-like tubes crammed with electronics. These tubes are guaranteed to catch the attention of airport security. Every time we try to check into a flight with them, we are questioned and searched.

We made it onto the plane. Lists had been made and checked, experiments designed and discussed, travel arrangements made and verified, equipment checked and packed, and the adventure was beginning for real. The plane took off, and we all worked on papers or other materials to offset the time we were losing to a day of travel.

We had left our comfortable homes typical of the middle class in the United States, and arrived in Panama City around 10:00 pm after a long day of travel. I had started at 5:00 am. We boarded the plane in North America in February, wearing jeans and long-sleeved shirts and stepped into a hothouse climate as we exited the airplane.

The wet tropics smell unique. If you have never smelled it before, it is hard to describe. If you have smelled the tropics before, the sensation rushes back at you every time you return, like the smell of grandma's closet never quite leaves you. It is a sweet funk that never develops, even in the summer, in temperate climes. It is not the reek of party effluvia that courses through Bourbon Street, but part of that odor is there. The odor, in part, is spiced by the perfume of tropical flowers that always bloom where there is no winter. Flowers that would smell like sleazy perfume in a cheap bar, were they not the real thing. The odor is part mashed bananas and citrus, slightly fermenting. The smell is mixed with the musk of fungus and rot encouraged by moisture and continuous temperature optimal for growth of microbes.

Humidity envelops the traveler immediately as they leave the confines of the temperature controlled jet. On my walk into the terminal, the heat and humidity, the smell, and the language on the signs and of the travelers in the airport affirmed that I was not in Kansas anymore.
We stumbled through immigration and the Panamanian officials only took a cursory look at our passports. They obviously wanted to go home and we were clearly not a threat. We made our way to the baggage claim, where we met with some of the members of the party who were already in Panama City, Roberto Brenes (a student from Matt?s department), Edgardo Griffith (hired to live in Panama and help with the project) and a couple of temporary workers on the project.

Edgardo made a strong impression at first, but I did not realize he would end up being one of the central figures in this story, and that we would make a strong bond of friendship over the next few years. Edgardo is a large personality, so difficult to tell how tall he is. He has dark skin, curly hair, liquid brown eyes and a huge smile with prominent white teeth. He wears the clothing of youth with large sagging shorts and t-shirts. Edgardo has the Creole look of Caribbean jambalaya heritage, difficult to put a finger on, maybe some African, some native Indian, and some Spanish. Whatever, I suspected that he has little trouble getting noticed by women. More importantly his gregarious smile puts everyone at ease immediately.

There were lots of bags and it was to be expected that it would take awhile to get them all. After the last bag came off the carousel, mine still had not appeared. Shoot! Immediately I started thinking through what equipment I had that we might have to do without. I was glad that I had carried on my digital camera and wished I had carried on my toiletries. It was obviously going to be a late night because we needed to fill out the baggage tracking forms. Luckily Edgardo helped with the baggage claim service. My Spanish is good enough to get a hotel, a bathroom, a drink and a meal with a bit of struggle and copious hand signals. Describing a lost bag and understanding how the airline would deal with it was beyond me, and the airlines had no English speakers on duty. Edgardo settled things as far as they could be settled and gave them all our Panamanian contact information.

The lure of exotic research locales

2009-07-28T12:53:00.000-07:00

Our group was typically atypical of ecologists. We all love the natural world, but few of us are content to always stay close to home for our research. We build on a long tradition of scientists who travel to exotic locales for scientific research.

From Carl Linnaeus and before, since Charles Darwin was selected to accompany Captain Robert Fitzroy on the second voyage of the Beagle, naturalists have sought opportunities to study abroad. While few have had a fraction of the biological impact that attained by Linnaeus with his nomenclature system and by Darwin following his voyage and subsequent Theory of Evolution, many of us are drawn to the adventure of travel and the lure of discovery in exotic locales. Somehow, seeing new ecological systems improves the chances we can make more general predictions about all ecology.

The desire for exotic research is, for some, a contradiction in values. As ecologists we understand the environmental costs of burning fossil fuels to travel vast distances for research. As international citizens we understand the abysmal poverty that is the yoke for so many on Earth. Why should we use resources to travel halfway around the world to study what most people view as insignificant animals, plants, and microbes that inhabit streams?

Our use of resources can only partially be justified by some of our lifestyle choices otherwise (some of us recycle, bicycle to work, turn down the heat and up the air conditioner, etc.). Still, most scientists that study the natural world have a very large footprint. In my book, Humanity’s Footprint, there is detailed discussion about how those that live in the developed word are “cheaters” that take advantage and use more than their fair (sustainable) share of the Earth’s resources. There is also detailed discussion about how being a “cheater” is deeply ingrained and evolved human behavior, much of which is not likely to change. Scientists are perhaps the most hypocritical because they understand the global environmental problems, have a solid concept of how their lifestyle influences the environment and still continue to use more than their share. I am a “cheater.”

Still there are some positive aspects to travelling to developing countries to do our work. We are much like any other eco-tourists, albeit more educated in the subject of ecology. We spend money in developing countries. W are different because we work with the locals, pass information and training to those who have less access to research universities and all their benefits. We are the same because we come to see the last places on earth that have been minimally impacted by humans, and resent others who despoil our private natural experiences. Like all eco-tourists we resent the presence of people while we ourselves make the last places on earth a little less wild.

The compulsion to research in exotic parts of the world has among other things, caused researchers to contract exotic tropical diseases, torn apart personal relationships, and kept some from advancing in their careers. Some ecological research trips are conducted under dangerous and extremely primitive conditions, require an exhausting schedule of mind-numbing work, and are physically and psychologically draining. Some research is done in dangerous political areas; guerillas and rebels tend to favor hiding in remote, relatively pristine natural areas. The most extreme research expeditions still are worthy of the status of a National Geographic special.
Much of this kind of extreme ecology seems testosterone-driven. It is mostly, but not only men who have fallen under the spell of such extreme study areas. Some will undergo tremendous hardship to ask a scientific question that could be answered much closer to home. Take for example much Arctic and Antarctic research. Many of the questions could be approached by study of high-altitude habitats in the United States and Europe. The justification for some of the grant proposals (what we call intellectual merit and broader impacts) often seems contrived. The grant agencies are as influenced by the romance and adventure of this extreme research as are many researchers and still are fond of funding such ventures.

The exotic research casts such a strong spell, ecologists go through the tedious process of writing grants, begging leaves of absence, leaving behind family and eagerly pursue the next trip. The adventure is as addicting as the possibility of unique scientific discovery. Being able to tell an impressive story to fellow researchers at the next scientific conference is an additional reward.
Sometimes, however, the only way to accomplish a research project is to travel to an exotic locale. The frog extinctions of Central America are a case in point. As the wave of extinctions spreads down Central America, the possibility of ever studying these animals in the wild and how they are related to their environment disappears as well. Many researchers who study tropical species have found themselves working in front of a wave of extinction; they rush to document species and ecosystems that are rapidly disappearing and may never be seen in the wild again.

This global spread of extinction has let to ecological “swat teams” that rush to collect as many unique species as possible, and document ecosystems before they disappear. These groups of specialists are made of taxonomists of various specializations (for example a botanist, a mammalogist and an entomologist). They work in front of the path of loggers and developers in the highest diversity habitats on earth. This can be depressing work. The swat team rushes to take specimens, usually not living, before the species disappears from earth forever. Our group was a similar “swat team” rushing in front of the disease wave.

A motley crew

2009-07-20T07:01:00.000-07:00

The immensity of the loss of an entire group of animals was abstract to me, until I took my first trip to Panama and saw a jungle stream teeming with so many types of frogs I had never seen before in my life; so the story begins with the trip to get there. Most of our research group met in February 2006 in the Atlanta airport to fly to Panama. This was an eclectic group of individuals who are science nerds (Ph.D.s), globe trotters, adventurers, and generally workaholics. Our common bond is a drive to understand the natural world. Everyone in the group has research experience in aquatic ecology around the world; studying streams is the thread that flows through all of our lives. Matt Whiles, Bob Hall, Alex Huryn and I were the lead researchers that traveled together on this trip.

Our connection in Atlanta was tight, and a bit of running was required to make it from the domestic terminal to the international departure gates. Bob Hall is the kind of person who is amusing to watch run for an airplane. Although I am told he is an excellent skier, he is tall, gangly and awkward looking when he runs, like a camel or a stork. He has the look and the accent of an Ivy League aristocratic intellectual. Bob looked a bit worse for the wear because he had recently returned from a research trip to streams in Venezuela and had not yet decompressed from that experience. He had a touch of the Chavez’s revenge as well.

Currently, Bob is an Associate Professor at the University of Wyoming. We have been friends since we met years ago in the North Carolina Adirondacks. We were attending a workshop to explore the use of stable chemical compounds to trace movement of elements (nitrogen) in streams. This new technique opened up an extremely productive area of research. We could use it to dissect out the basic processes that nourish all the plants and animals living in the streams. The method ultimately allowed comparison of streams from the tropics to the tundra, and resulted in a large project and ultimately a publication in the prestigious journal Science. Many investigators never are able to publish in this journal, as it is one of the top scientific outlets in the world and extremely competitive to get papers into.

It was our expertise in this tracer method that prompted Matt to involve us in the Panama project. In North Carolina, Bob and I hit it off immediately when we discovered our shared interest in home brewing. He had brought several small kegs of some of the best and more exotic beer I had ever tasted, a fact guaranteed to make me sit up, sip up, and take interest. Bob has since published some of the seminal papers on how animals and other organisms mediate movement of nitrogen through stream environments.

Alex Huryn was at the gate when I arrived. Alex is tall and slender, with a matching ambling bearing, thoughtful personality, and a preoccupied air. Many ecological researchers of my generation never left the 1970’s with regard to their hair, and between Alex’s brown hair over his collar and a substantial mustache, it was unlikely that he would be mistaken for a businessman outside of the silicon valley. He has studied stream invertebrates across North America, including the tundra of Alaska. Alex did stints in New Zealand and Maine, among other places, before he landed at the University of Alabama. Like so many ecologists with a pedigree from the University of Georgia (Matt and Bob included) he has a reputation for top level ecological research and partying hard, presumably to balance the tremendous intellectual and work load required to answer the questions that they doggedly pursue (or maybe that is just the excuse). They don’t call them the Georgia bulldogs for nothing.

I had seen Alex out-on-the-town at conferences. The last time I had seen him, he had crawled across a dance floor in New Orleans and bit me on the calf. The bulldog connotation again comes to mind. Before being bit on the calf, I had admired his research papers, but did not know him well. I was hoping he was easy to work with, but was not sure given our prior interaction.

Matt Whiles had a delayed flight from St. Louis and came to the gate at the last minute. He has been a close friend of mine since the 1990’s when we worked at Kansas State University together. Now he is a professor at Southern Illinois University in Carbondale. He is a very gregarious person; people are compelled to tell him their secrets for some reason, probably his friendly face. He has hair about the same as Alex, another child of the 70’s. Matt is gifted in the art of diplomacy and a perfect leader for a group such as ours with strong personalities and the professors’ common trait of always being certain of being right and ready to argue the point exhaustively.

Personalizing Extinction

2009-07-13T10:10:00.000-07:00

This is a tale of loss and how people respond to loss. Few people know frogs are disappearing from the mountains of Central America. Those who do, can’t do anything about it. All we can do is to try to understand the loss. The context of Panama is important to the story as is the way that scientists relate to such an event in the natural world. Thus, this story is a research log, a travelogue, a description of natural history, and a documentation of one part of one of the great extinctions occurring in our lifetime, perhaps in the history of life itself.

I am not sure if most people even care about species extinctions in any real sense. When young, my goal was to do something with nature. The realization that people were actually paid to live out in the wild made the career of park ranger extremely attractive to a fishing/ backpacking 5th grader. Then, a trip to the Mediterranean as a young teenager got me into a snorkel and under the sea for the first time. I could not believe what was in front of my eyes…coral, fish, algae, and marine biologist seemed like a dream job. In college I was seduced by the idea of pre-med and the ideal of helping people. Upon deeper reflection, the things that really excited me in the past revolved around nature, not around being a mechanic to fix humans. The grades and test scores were there for medical school, just not the desire. So my path went toward ecology as a graduate student.

After school and work in Oregon and Montana, I landed in Kansas. How can an aquatic ecologist move from those places to the flat, dry Midwest? Well, supporting a family and the option of a paying job was quite attractive. Yet, it did not take long to develop a deep connection to Flint Hills Tallgrass Prairie and particularly the streams that drain it. The streams are clear, clean, and full of fascinating algae and aquatic animals. Kids love to wade in streams and turn over rocks, I just never grew out of that phase.

I am what E. O. Wilson calls a biophile, a nature lover. Many ecologists and taxonomists spend their lives studying the natural world because they too are biophilic. Others take nature up as a hobby and watch birds, camp, fish or hike. But these are the exception, most people want nature at an arm’s length. An animal show on cable TV is ok, maybe a cute movie about penguins. The dirty business of actually being in nature is so far from most peoples’ everyday life, that they cannot be expected to care much about the loss of a few species. To someone who has this deep attachment to the unbelievable diversity of life on our planet, extinction is a troubling idea.

The story of extinction is not dramatic. As Elliot says, the world ends “not with a bang but a whimper.” Extinction is the quiet catastrophe going on all around us now. The amphibian extinctions are emblematic of the fate of many species and how much of humanity is disconnected to that fate. Chris Cokinos in his book “Hope Is the Thing with Feathers: A Personal Chronicle of Vanished Birds” and Douglas Adams and Mark Carwardine in “Last Chance to See” both dealt with extinctions. The former deals with the emotional toll in very direct terms, the later is seasoned with Adams’ humor which diffuses the anguish of experiencing species extinctions. Both books served as inspiration to my attempt to put extinctions of some species into context and convey the personal side of watching species disappear from the earth forever, while describing how scientists are documenting the effects of such disappearances.

The extinctions and the opportunity

2009-07-06T06:38:00.000-07:00

My conversations with Matt also included his frank assessment that high altitude frogs that lived in the speciose tropical jungles of Central and South America were going extinct. Matt had been to other sites and experienced the disappearance of the frogs. My knowledge of amphibian declines remained academic. But, Matt’s concern spurred me to look more deeply into the literature. What I found there was startling. Matt was just telling a small part of the story, albeit one that involved the potential extinction of tens of species or more.

It was clear that amphibians everywhere were declining or disappearing all together. The causes of amphibian declines and extinctions were not generally agreed upon at this point and were a matter of debate. The fact that declines and extinctions were occurring globally was becoming more and more alarming to the herpetologists who study frogs, toads, salamanders, and reptiles around the world.

What is particularly worrisome about many of the declines is that they were happening across the world’s natural areas, often in relatively pristine habitats. Southeast Australia had been hard-hit. Many species along the Pacific coasts of North America were in decline. Declines were also documented from the jungles of northern South America and Central America. Madagascar, China, and the Atlantic coast of Brazil all had substantial numbers of threatened amphibians.
These frogs were being lost from among the most beautiful natural habitats occurring on earth. The luxurious jungles with their riot of plant, insect, and other animal variety are the cradles of biodiversity on our planet. These wet, warm habitats are perfect for frogs. The causes and consequences of amphibian declines are not always known or understood. Unfortunately, reports in the scientific magazines seemed to focus on the controversy over causes as much as the tragedy.

As a nature lover, thoughts of potential extinctions and their consequences were disturbing. Matt was offering the possibility of seeing the tropical jungle again, and this was enticing. The Central American jungle with its in-your-face diversity originally inspired my decision to become a field biologist rather than a laboratory chemist. These factors led me to get involved in Matt’s project. I tend to be protective of my time, travel takes me away from home and family, depletes research funds, burns fossil fuels creating greenhouse gasses, and impedes getting “real” work done. Now, I am glad I took the trip and did the research and the following story is a chronicle of travel to Panama, the people I worked with, the work we did, and the people and sites of Central America.

A phone call in the cold Midwest

2009-06-30T06:21:00.000-07:00

Twenty eight years after my trip to Costa Rica, I was sitting in my office in Kansas with the cold fall wind finding its way through the large cracks in my north-facing window. The Costa Rica trip was why I decided to become an ecologist. An ecologist is a scientist who studies plants and animals, as opposed to an environmentalist who is an activist to protect the environment. I am both, but chose this path instead of becoming a molecular biologist because of my tropical ecology experiences as a young undergraduate. Sitting behind a computer was a far cry from my romantic notion of a tropical field ecologist.

My friend and colleague Matt Whiles phoned me from his office at Southern Illinois University to ask for some help with a research project he had on frogs in Panama. He had described his research on effects of population declines of frogs previously and I was already interested. Now he needed help in areas that I was a specialist in to further examine the ecological effects of frog extinctions in Central America.

Matt explained once again how frogs were disappearing in the cool, high-elevation rain forests of Panama. He had been telling this story for a while, and the fact that the frogs were going was just part of the issue. Matt was worried about what would happen to the rest of the stream organisms when the frogs were gone. At this point hearing about the species extinctions was like hearing of the death of the aunt of a friend. It was about someone you never met. It was too bad, but there was a distance between me and the actual event.

Matt mentioned that algae populations had exploded in streams where the frogs had already vanished. He hypothesized the loss of frogs was responsible for the changes in the streams because the frogs laid their eggs in or near the streams and their tadpoles grew up in the streams.

From a scientific point of view this was very interesting to me; algae are central to how many streams work. We started talking experimental design and who else would be involved. We settled on a method to analyze ecosystem functions that we had earlier used successfully on tallgrass prairie streams in the Flint Hills of Kansas and started discussing travel dates and research plans. In retrospect this is how many scientists deal with tragedy, they compartmentalize and study it-- perhaps to avoid personalizing it.

An inkling of a problem

2009-06-23T13:58:00.000-07:00

This is a travelogue, a research log, and most of all an extinction log. It describes two research trips to gauge the effects of loss of frogs caused by a fungal disease that is sweeping through Central America. The story is one of extinction, and how people who study these animals respond to the loss. The story is a wake for lost diversity; we will never see these many species of frogs again in the wild. The blog also places the loss in the cultural context of Panama and the ecological context of the rain forest

In 1977, I visited the Costa Rican cloud forest preserve, Monteverde. The small park headquarters had an aquarium that contained a Golden Toad. I did not know at the time that this species was doomed to extinction. The animal was a beautiful, brilliant neon orange frog (Bufo periglenes), about 2 inches long. A staff person at the headquarters mentioned that this species had only been found in this one small area of this cool, wet, and high-altitude forest. He said that very few had been seen recently and we would be very lucky if we saw some in the wild. I had this in the back of my mind as we left to explore the cloud forest, but our main objective was to see the extravagantly colored Resplendent Quetazal, a bird with a two foot long bright green tail. I saw screaming monkeys, I was chased by a giant cat weasel (Jaguarondi). I never saw the frog in the wild.

In 1989 the last Golden Toad was seen, none have been reported since then. The news gradually filtered out through the scientific community that the toad was extinct, but the exact cause was not understood. Monteverde is a pristine cloud forest at the top of a mountain range; it was not developed, and should not have had much human influence. Yet, this extinction was to become emblematic; loss of this species was for many the beginning of general scientific awareness of a global trend of amphibian extinction. The extinction of the Golden Toad bewildered and saddened me, and came to mind when reading the articles that started surfacing in the 1990’s about amphibian extinctions elsewhere in the world. Little did I know that my experience with frog extinction would become very real in future years.