One thing is for sure: field research is messy. Not just in the sense that nature is full of mud and water and bugs, but in terms of logistics. You have to learn to expect the unexpected.
On Wednesday, we leave Gamboa bright and early—around 6 a.m.—and head north to visit a national park site near the Atlantic Ocean recommended to graduate student Angie Estrada. On the way we discover that the highway is curiously closed so we take the closest exit through a series of towns toward the city of Colon, stopping off at a grocery store to grab snacks.
As we get closer to Colon, traffic gets slower and slower. Finally, it comes to a stop. Graduate student Daniel Medina calls to a pedestrian who informs us that there is a protest in the middle of Colon that has resulted in the epic traffic jam. Taxi drivers are demanding that their cars be equipped with better security so they are not stolen from.
Panama is currently in a state of political agitation after suspected corruption during the last presidential term. Now that a new leader is in power, people are feeling more empowered to exercise the right to protest, Angie and Daniel explain. The roads are impassable: we have to turn around and head back to Gamboa.
Angie is bummed. She only has a small amount of time to visit all of her sites in order to get an accurate portrayal of frog populations in the dry season here in Panama. She decides that in no way will the day be wasted. She and Daniel head back to the Pipeline site to lay transects, or measure out the space for frog swabbing for another day.
Around 8:30 p.m. that evening—Frog Prime Time— we embark on another field excursion that is a first time for me: night swabbing.
It takes a great deal of convincing for me to step into my rubber boots, long sleeved shirt, pants, and bucket hat with net (not pictured: massive amounts of Deet-filled mosquito spray). To say that shuffling around an unfamiliar jungle at night is unnerving to me would be an understatement. As a kid I spent a lot of time playing outside in the dark, but adding jaguars and venomous snakes into the equation is a game changer for me.
Nevertheless, I decide to go because this is an important part of the research project that Angie and Daniel want me to see.
We drive about ten minutes out of Gamboa and park on the side of the road in a spot that Angie and Daniel must know by memory, because it all looks the same to me. Angie pulls aside a branch on the side of the road and there it is: Ocelot Pond glimmering in the moonlight. It’s a short but steep trek down to the small pond and the researchers tell me which trees to grab onto and which to avoid (the spiny ones).
We are three little headlamps in the night moving towards the water, some of us more gracefully than others. I feel like a water buffalo in my big rain boots on the uneven ground. We have to be sure to shine our lights on any branch we aim to touch or pull for leverage—that’s the nature of a rainforest at night. On the forest floor, we see colonies of leaf-cutter ants hoisting their leaves overhead and marching in the straightest assembly lines: nighttime shift work.
Our first spotting isn’t a frog at all—it’s a Common Basilisk, more commonly known as a Jesus Christ lizard for its ability to run on water. We saw one sprinting over a stream at the Pipeline site, but this one is in no mood for exercise: he has found a comfy spot on a branch partially sunk in the pond. Up close, he is fascinating and bigger than I imagined, about the size of a small iguana. I am struck by the fact that he lets us get within inches of him and Angie tells me it is because he is sleeping.
It’s not long before Daniel is clued into the calls of the frogs—he is an expert at this—and he is able to name the species based on their calls. We continue around the pond, with Daniel and Angie combing branches, leaves, and the pebbly soil for signs of webbed feet.
We are looking for two key species at the pond: the hourglass frog and the glamorous red-eyed tree frog that has long served as a rainforest poster child. These species are important because there is two years’ worth of swabbing data for them, and therefore a strong line of comparison.
Luckily, we find both of these species for swabbing, but not without also finding the grandfather of the frog pond (pictured left): Leptodactylus savagei (Savage’s thin-toad frog). This frog is HUGE, anything but thin! And also fast. We try to catch him for swabbing but he makes a getaway.
In the back of the truck, Angie and Daniel organize the supplies to ensure a quick and efficient swabbing station. It’s not good to keep the frogs in their sampling bags for too long. Daniel handles each frog with laboratory gloves, turning it so that Angie can swipe its belly, back and legs. The procedure must be exactly the same for each frog.
They sample a total of seven, and this is low, even for the dry season. During the rainy season, the forest is full of frog calls, Daniel explains.
The swabs are important because they reveal the microbial communities on the skin of the frog and whether or not the frog is infected with chytrid fungus throughout the dry and wet seasons.
The researchers are also interested in the frog population dynamics of each site, because it helps them understand the spread of chytrid fungus in the same way that human population dynamics help us understand how we spread of the flu to each other.
Many factors are at play, including frog behavior, biological defenses, and environmental conditions. This is complicated by human-driven changes such as climate change, invasive species, pollution, and habitat degradation.
It will take a team of scientists studying many angles of these factors in order to get a handle on the disease that has infected approximately 500 frog species so far. Scientists have claimed chytrid fungus to be the greatest disease-caused loss of biodiversity in recorded history.
Daniel, Angie, and other scientists studying the disease across the world have their work cut out for them, but we are done for tonight. The frogs are released back into Ocelot Pond and we head back to Gamboa with a cooler full of samples.