The First Experience with the Jungle Stream

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.

Flying to Panama

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.