The Adventures of the Field

By Dennis Bolshokov

          Before coming to Costa Rica, I had never thought of scientific studies as adventures. The ones I had been a part of before had all taken place in a lab, with a controlled colony of the species we were studying. Even though I knew about field studies, I had always had the perception that they were carried out in small, rectangular plots, requiring meticulous, repetitive attention. Of course, studies like this are extremely common and important (and almost all science has some repetitive aspect to it), but little did I know that there are more adventurous possibilities out there.

            In the past three weeks, the Tropical Biology OTS group had the opportunity to participate in three field-related studies, as well as many walks through the forest and gardens at Las Cruces to observe birds, nocturnal animals, and plants. Of the three studies I mentioned, one was a long-term study of ants at coffee farms, and two were faculty-led projects at Las Cruces. The coffee project was really cool to do because we had just finished learning about how coffee is grown, processed, evaluated, and sold, as well as how the market for coffee has shaped the communities that rely on the crop. Walking through the rows, I sometimes wished I had a machete to make it through the thick, overlapping branches (something I have not needed in the jungle yet). We lured the ants with vials full of tuna, monitoring how long it took for the vials to be discovered and how many ants came to partake in the feast. Later, we took the vials back to the lab to identify the species of ants present at each site.

The Lizard-catching crew. We were unfazed by the swollen river or the recent mudslide behind us. Photo creds: Ray Hopkins

            For one of the faculty-led projects, we walked down different streams in the jungle, and looked for aquatic anole lizards. Dressed in rubber boots and baggy ponchos, we ambled through the streams, precariously avoiding deep spots and fallen trees. Mind you, this was during the tropical storm that became hurricane Nate (further up north) and flooded much of Costa Rica, so the streams were very swollen and turbulent. Despite all this, it was extremely fun to look for the lizards, and then to catch them (which is done by using a cupped hand). We put the lizards in plastic bags, and measured them in the lab, then released them in the same spots we caught them in the next day.

The last faculty-led project involved spiders. This study was designed by us students, and everything relating to the methods was concocted by us, with minimal guidance from the faculty. Basically, we were testing if wandering spiders (genus Cupiennius) learn to avoid distasteful prey faster under a red or a blue light (we used flashing Christmas lights). Although the trials were carried out in the lab, we needed to catch the spiders first, and this was the most fun and exhilarating part. We went out at night with headlamps to capture the spiders on bromeliad plants right outside of the house. Mind you, these spiders are big. Although not as venomous as their infamous cousins in Brazil, these ones could still pack a punch. We did this in the pouring rain, with just plastic bags and sticks to tap the leaves. One person sheathes the leaves with the bag, while another guides the spiders with the stick or scissors. Most of the time, the spiders did not want to be caught, and hide in the water-holding “tank” part of the bromeliads. One time, a spider jumped off the leaf and onto my hand, then onto the ground, and I thought of an adjective I never considered thinking of for spiders before: cute. It hopped (hopped!) across the path and into hiding. Every time we caught a spider there were cries of jubilation; one girl who couldn’t bring herself to hold a lizard a week ago captured several of these scary spiders and screamed with excitement every time! It was a blast. After the study was completed, we released the spiders back into the garden and spent two days writing a scientific report about the studies.

            Another day, we went birding in the gardens, and saw all kinds of colorful parakeets, toucans, tanagers, and more. There are also really big birds that fly here, among them caracaras nesting in palms, and guans. It’s really remarkable how diverse and colorful life is here. Even though learning to identify the hundreds of species here would be difficult, it makes one appreciate the tropical adventure even more.

Getting Over Fears One Catch At A Time

By Finote Gijsman 

I wouldn’t exactly consider myself an arachnophobe, but I definitely would not say that I am a fan of spiders. So you could imagine myreaction when I found out that the faculty led research project I would be working on involved golf ball-sized spiders. Our professor was Jenny Stynoski, a scientist who has been studying poison frog research, investigating the defense mechanisms of the Strawberry Poison Frog (Oophaga pumilio). Our project looked at colored-based learning and prey selection of wandering spiders in the Cupiennius genus of the Ctenidae family. These spiders have been shown to avoid aposematic prey like the Dendrobatid dart frog Oophaga pumilio so we were trying to determine whether these spiders would learn to avoid unpalatable prey under aposematic visual cues – in this case, a red flashing light.

             On the night before our project, our professor gave us an introductory lecture explaining the scope and methods of our experiment. Jenny assured us that these spiders would be easy to find and catch and that it was okay if we weren’t completely comfortable with catching them yet. Although it was somewhat comforting to know that Jenny was also very afraid of spiders, the thought of going out at night hunting these spiders terrified me. “You’ll just have to wrap the Zip-lock bag around the leaf of the bromeliad and, when a spider enters the bag, zip it up tight”, Jenny told us. Easier said than done.

            On the first night of our spider collections, it poured rain. These evening showers were not a new sighting, but we were all still surprised by the sheer amount of rain that was falling that night. Our goal for the night was to catch 20 spiders. The garden at the Las Cruces Biological Station is covered in terrestrial bromeliads, so catching 20 spiders that night seemed like a feasible goal. The four of us split into two groups and covered different areas of the garden. The first 20 minutes of our collection were unsuccessful. The spiders seemed to be just as irritated by the rain as we were. Our clothes were drenched and glued to our bodies. My ankles were soaked in a layer of water that lined the inside of my rain boots.

            Despite the unideal working conditions, we continued to search for these spiders around the station’s garden. Little by little, our search efforts paid off. We found spiders hiding underneath the leaves of the bromeliads, trying to avoid the rain. Every time a spider was spotted, we would surround the bromeliad plant and plan out our scheme of attack. As one person gently wrapped the bag around the bromeliad leaves, the other would use the end of a ruler or a scissor to try to guide the spider into the bag. The job was not very easy. These spiders are extremely sensitive to vibrations so any kind of disturbance would scare them right off of the leaves. A lot of the times the spiders would also outsmart us and jump into the puddles of water found in between the leaves of the bromeliads. Once they were in those small openings at the base of the plants, finding them was near impossible task.

As the night progressed, the field work became more and more fun. We found a group of bromeliads on a hillside by the dining hall that were covered in spiders. Up until then I had been the one guiding the spiders into the bags with a ruler. Jenny had warned us that these spiders were able to bite through the plastic bag and told us about her wild hallucinations when she got bitten by one, so I definitely was not planning on being a victim to these spiders’ fangs. However, the more collections I got to be a part of, the more I got used to them and the more I started to build up my courage.

By 8:30pm, we had caught a total of 15 spiders. Our group had gotten a lot better at spotting and catching them and had developed a routine that was followed for each collection. With only five spiders left to catch, I was determined to catch one on my own before the end of the night. I walked over to the edge of the hill of bromeliads and flashed my light on what looked like a giant cricket sitting in between two of the bromeliad’s leaves. My flashlight wasn’t very bright so I called over my partner to try to help me figure out what it was.

Shocker, it wasn’t a cricket. There were three large spiders, all sitting on the edge of the bromeliad leaves. I knew this was my last chance to catch one. I prepared myself for the catch while my partner tried to find the best angle to approach them. I opened up the bag and reached over the bromeliad leaf. My hands were shaking. Interestingly, my shakes helped disorient the spider well enough for me to be able to zip the bag quickly enough. I screamed through the entire process, but I had finally caught one on my own.

With these three spiders in hand, we only a few were left for us to reach our goal. Satisfied with our collections, we packed up our things and headed back to the house to call it a night. Although we were all extremely wet and cold from being out in the rain for two and a half hours, we were thrilled about the fact that we had collected all of the spiders that we needed for the experiment the following day.

            This project really got me out of my comfort zone and pushed me to face my fear of spiders. I definitely have not totally gotten over that fear, but I am proud that I took this opportunity to face it and make progress on it. I even surprised myself by offering to help the second group catch spiders the following night! I’m excited to see what other challenges are going to be thrown at me this semester, and I look forward to getting involved in other creative projects like this one.

Lizard Hunting in a Swollen Stream

By Tyus Loman

          Today was the first day of our faculty led projects in the Estación Biológica Las Cruces. four OTS students, including myself, and Mau, set out on a gloomy morning in search of anoles, led by Michelle Thompson, an ecologist who had been studying amphibians and reptiles in Costa Rica for her Ph.D. The task for the day was simple: find anoles, capture anoles, mark the capture site, take them back to the lab to measure and record data describing morphological.

We had hiked trails at Las Cruces over the last week, and we had easily found plenty of anoles. On this day, however, conditions would not allow for such easy anole collection. That morning brought the first morning rain since we had been there, starting with a strong drizzle at 7:30 am. The rain itself was not upsetting; however, it would make most anoles difficult to find. We split up into groups of two, searching the dense vegetation on the sides of the trails to no avail. There were no signs of anoles, most of us failing to even spot a frog. The small, cold-blooded vertebrates were too susceptible to the cold temperatures to be out on a morning like this. Still we hiked on, continuing to go off-trail to search for the small lizards as the rain picked up. 

           After around two hours of unsuccessful anole searching, Michelle decided to change the experimental design. Previously, she had studied stream-dwelling anoles called Norops oxylophus while doing research in La Selva. She was aware that a closely-related species to N. oxylophus could be found in Las Cruces, a species called Norops aquaticus that also dwelled on perches near streams. We chose to leave the dense vegetation and head for the streams.

            Split into groups of three, each group searched a different part of the stream. My group closely examined rock walls and other perching sites for the aquatic anoles. As we walked downstream, things were relatively easy. Outside of the occasional slippery rock, we could generally avoid falling into the stream. My colleagues found a few anoles, while my grand total of anole sightings remained at zero. Still, the entire time we searched the rain came down harder and harder. On the way back upstream, the stream had swelled massively, increasing the flow strength and the difficulty of maintaining balance. The water level rose by about two feet, and rocks I had used as foot holds were now completely submerged. On a couple occasions, I slipped and fell into the stream, completely submerged under the water. Still, I had not captured a single anole, but my colleagues found enough to compensate for me.

              Eventually we made our way back to the research station, thirty minutes late for lunch and completely drenched from head to toe. Still, despite my lack of success and the non-ideal weather conditions, I found myself to be in good spirits. As someone who has lived his entire life near the ocean, I have always had great affinity for water. Even though the stream was not much of a swimming hole, just the idea of being in water was enough to lift my spirits. No matter the conditions, I am a water mammal. As well, the stream and other bodies of water serve as habitats to a multitude of different plant and animal species. The entire experience reaffirmed my belief in ecological conservation. As people, we should always work to preserve these wonderful ecosystems, along with the rest of nature that most people do not get to experience.

Searching for Jaguars

By Genevieve Valladao

Costa Rica is one of the most biodiverse places in the world. It is full of remarkable species that people travel from all over in hopes of seeing. In my month and a half in Costa Rica, I’ve already seen many amazing animals, including Howler Monkeys, Chestnut-mandibled Toucans, White-faced Capuchins, and Fer-de-lance snakes. However, there is one animal that I want to see more than all others, but this one is also among the most difficult animals to come across. The animal I most want to see is the Jaguar.

Although Jaguars are widely distributed across Costa Rica, this population is fairly small. Jaguars require large home ranges – males need about 5,000 hectares of land – so even when jaguars are present, the area inhabited by just one spans a massive area. Although the Jaguar is the largest feline in the Americas, they are very elusive, moving swiftly through the forest making little noise. Like other cats, Jaguars have excellent hearing and nocturnal vision. They are crepuscular and are most active at dawn and dusk.  

The range of the Jaguar in Costa Rica. Image courtesy of Project Panthera.

             I was thrilled when I found out about an overnight trip our program was taking to visit a conservation area called Las Alturas. The station we would stay at borders La Amistad International Park and is in a private reserve that is largely primary forest. Such pristine land coupled with the large amount of it, over 410,000 hectares, meant one thing to me – Jaguars might live there.

When we got to the station we learned that Jaguars definitely do live in the reserve. Camera traps installed in past years have observed a relatively large population of 16 different individuals. As soon as one of my friends on the program, Anna, and I found out that there were Jaguars in the forest around us, we knew that we had to do everything we could to increase our chances of seeing one. To this end, we planned to wake up early the next morning and to visit the forest in complete silence, as the sun was coming up.

At 5 am sharp, my alarm went off simultaneously with Anna’s. We locked eyes from our beds and nodded at each other. The seven other people sleeping in our room had forced our morning of silence to begin before we had even left the station. The sun was just starting to come up, turning the sky orange, as Anna and I met on the porch to put on our rubber boots. “Want to watch the sunrise first?” I offered her as we headed down the steps of the station, towards the forest. “Nope, we’re up to look for cats.” Anna and I were on the same page.

We started into the forest, walking in complete silence, an uncommon state for the two of us. The previous night we had discussed finding a spot well down the trail away from the station to sit, wait, and watch. I knew that was what we were looking for. After walking for about ten minutes, we started to hear running water. Right as I was about to tap Anna on the back to tell her that we should find a place near the river, she turned around, nodding her head towards a small path off the trail. I followed her about 100 meters down a slope, to a quiet pool of water made by a small stream. If there was anywhere we were going to see a jaguar, it was here.

We found a fallen tree near the stream, sat down on it, and started to take in what was around us. As soon as we had settled in and stopped making noise, birds started calling and colorful butterflies started gliding by us. As the minutes ticked on and the sun rose, the forest began to light up. It was amazing to watch the sun illuminate different layers of vegetation that had been covered in darkness when we first got to our spot.

After an hour and a half of quietly pointing different plants, insects, and birds out to each other, Anna broke our silence. “You know they definitely wouldn’t have let us come out here if they thought we actually would see a jaguar.” I laughed in agreement and nodded. Not only had we failed to encounter a jaguar, we hadn’t seen a single mammal. Anna and I stayed on our fallen tree for the next 20 minutes catching up with each other before started to hike back to the station to make it in time for breakfast - neither of us ever miss breakfast. Knowing that our opportunity to see a jaguar had passed, we talked and laughed the entire way back.

Although I am unlikely to see a jaguar during my time in Costa Rica, I’ll keep searching for one. Watching the forest function without the human disturbance that I usually bring and time spent with my friend made my morning excursion well worth the early wake up and the short hike.

The scientist, the politician, and the…do-er?

By Mikayla Kifer

            Should science be useful? There is no clear answer to this question. Robert Lackey in 2007 expressed concern that scientists have been slipping to the point of allowing their personal political goals to influence their work. He believes that scientists should refrain from using words like “healthy,” “degraded,” or “poor,” to describe aspects of the natural world. Science, after all, is meant to be descriptive (making statements about what things “are”), rather than normative (making statements about how things “should” be). Making normative claims about the world risks both the integrity of science and the privilege of having scientific knowledge respected and taken seriously. In essence, Lackey argues that we should leave science to the scientists and decision-making to the politicians—it’s their job, after all.

            In many ways, I agree with Lackey. Science is meant to be the pursuit of truth, untainted by human preference and bias. If we can’t trust scientists to represent the truth accurately, then who can we trust? But, as always, reality is not so simple. Lackey’s system makes sense provided that a strong infrastructure exists for translating unbiased scientific findings into policy and action. After scientists publish studies, their work should be taken up by an army of philosophers, economists, and anthropologists to determine how it can and should be applied to policy-making decisions. Then politicians should educate themselves and decide how to implement this new knowledge. In this system, scientists can happily be scientists and know that their work will be considered and applied as appropriate.

            Unfortunately, no such infrastructure exists. As it stands, scientists have to be their own advocates and it is a constant struggle to get most politicians (at least in the United States) to take any science seriously. So it makes sense that scientists sometimes use a few normative phrases to get their point across.

            Clearly this system isn’t sustainable. These are the times when we most need scientific knowledge translated into action. Many scientists do their work because it’s interesting to study the natural world. But most also care about preserving the amazing nature around them. Despite this goal, although vast amounts of scientific knowledge are generated that can mollify and repair human influence on the natural world, so much of it never makes it beyond the journal pages and literature cited sections. This is work that matters, but, though desperately needed, it is rarely applied.

            For instance, we recently had a lecture about habitat fragmentation and learned that planting live fences (where tree limbs that are planted as fence posts eventually grow into trees) can reduce the effects of habitat fragmentation by acting as habitat corridors for some species. Amazing! What a breakthrough! But what will come of it? Some educational efforts undertaken by organizations like the Las Cruces Biological Station can encourage farmers to plant live fences if they need to clear pasturelands. But with thousands of papers being published annually, educational organizations can’t keep up, and governments rarely try to.

            The bottom line is that we need people who can translate scientific findings into reality. It is unfair to burden scientists further by asking them to produce their work and aggressively advocate for it. There aren’t enough hours in the day for that. We need people to fulfill the hopes of researchers by bringing their work into the world and putting it to use. Before students commit to saving the world as scientists, they must consider whether their work will actually make the world a better place. The cold reality right now is that the knowledge is there, but it’s not being adequately utilized. When more people realize this, I hope that we will build up and strengthen those institutions that allow scientific intentions to become reality. Once we can really start translating science into action, we have a chance of reducing the effects of climate change and other forms of human destruction of our world. 

Paradise of the Páramo

By Tyus Loman

          Our car filled finished its ascension up from the Estación Biológica Cuericí. We pulled over to the side of the paved highway, where we met with a blonde woman named Jayne, whom I soon learned had spent her entire life in the Costa Rican páramo. She led us further down the road, until we abruptly turned right, away from the highway. Suddenly, we were in a small immediate clearing, covered with limited vegetation including shrubs and grasses. Beyond the clearing, endless hills and mountains of green surrounded us, extending in all directions. I am from Los Angeles, California – a dry desert with limited green, especially in the hilly areas of the city. The environment I then found myself in was new to me; rarely had I ever seen so much uninterrupted natural land, as even in US National Parks the presence of humans is always apparent. I knew that the opportunity to experience the páramo ecology with my small group of twelve, without a trace of any urbanization or vehicles, was one I was lucky to be afforded.

            We began hiking up a trail on the nearest hill, a trail so narrow I would have missed had I not been with our guide. The surface was rocky and dry, a comfortable hike outside of the steepness and altitude. The sides of the trail were dense with berry bushes; some were young blueberries that were healthy to eat, while Janie informed us that a similar looking berry, one which looked like a blueberry with a crown, was slightly poisonous. I broke a small branch of blueberries off a bush, and fed on the small berries hardened by their young age and cold weather. We stopped at the top of the initial hill, where Janie introduced us to a species of grass that was scattered throughout the area. The grass had a sharp edge to the point where running my finger quickly on it would have resulted in a cut.

            When we reached the top of the first hill/mountain, the landscape flattened out. Everyone took pictures of each other, eager to capture the vast landscape not covered by clouds. Once we had enough, we continued up the next hill to the next point. Near the top of the next hill, the group stumbled upon an alligator lizard – a beautiful, blue and green colored, quick little creature not quite the length of my hand. We were lucky to have caught it, and we all took turns holding the small lizard, while some people in the group allowed the lizard to nibble their fingers. At the next mountain peak, we caught an Emerald Swift lizard. This one was smaller than the other alligator lizard we saw, with a brown and black coloration. By tickling its underside, we were almost able to lull the creature to sleep, and some of us with better cameras could capture pictures of the lizard with its eyes closed. Those were the only two lizards my group could capture and release, with many others being too quick and seeking shelter under rocks before we could even move.

            Along the way, we continued to identify more plant families. All the plants we encountered in the páramo were small in stature, shrub-like compared to the trees of Palo Verde and other Costa Rican habitats. At one point, we came across a small patch of moss that covered the rocky ground, comparing in texture to a carpet. Outside of the small lizards we encountered, animal life was limited, perhaps to avoid the intense UV radiation of midday. Bird calls were not noticed, nor were bird sightings. Eventually, we reached the fourth peak of our upward climb, one which had a telephone line planted in the middle of the mountain. We descended downwards on the muddier, rainier side of the mountain. I slipped numerous times, and my clothes had the proof of this.

          We took a break for about half an hour, and I reflected on the páramo I had just seen. I was grateful to have had the opportunity to visit a different country to study and explore a limited biome, in a country that understood the importance of preserving its natural beauty. The lizards, plants, and landscapes we saw were now more than mere pictures in a textbook. My opportunities to see such an environment again would be limited, especially as climate change pushed the endemic species out of their limited space on the summit of the mountains. When we finally descended the mountain, my group and I were disappointed our time in Cuericí was quickly coming to an end. Hopefully a return is in my future.

Dead Things!

By Ray Hopkins

This is skeleton and skull of a Black Spiny-Tailed Iguana (Ctenosaura similis). I’m not sure if it was a male or female, but I found it while hitting softballs out into the soccer field and brought it back to the station for an ID. At first I thought it might be a snake, but the teeth are too flat and indicate a more vegetarian diet, which, combined with the size of the skeleton, points to a big lizard. Ctenosaura similis is the only iguanid species at the field station, so it was an easy deduction. What was really cool however wasn’t the species discovery itself but the teeth.

      There are two kinds of lizard teeth, pleurodont and acrodont. Acrodont teeth have no roots, and as a result are fused to the top of the alveolar ridge. If these teeth fall out, they cannot be replaced in adulthood. This kind of dentition is common in amphibians and reptiles. However, these are pleurodont teeth. Lizards can have acrodont teeth, but pleurodont teeth are lizard-specific. Pleurodont teeth are attached to the rim of a jaw. Fellow student Michael spotted this and noted that the teeth, as you can see in the second image, are pushing outwards rather than being straight up and down.

A drawing of reptile dentition, courtesy of Wyneken, J. “Anatomy and Physiology of the Reptile Mouth.” Pet Education, PetCo Wellness, www.peteducation.com/article.cfm?creference,

In addition to finding deceased Ctenosaurs, I also found a very large and very dead toad this morning, likely a deceased Cane Toad, Bufo marinus. I didn’t think much of it, other than that it was pretty neat because I had never seen the carcass of an amphibian that had fallen prey to a predator. All the dead amphibians I had previously seen had been hit by cars or were cooked on the side of the road or fell victim to a parasite. There was never much to see until now. It looked like something had just ripped it straight down the middle and scooped out its innards as if with an ice cream scooper. It was really neat, the skin was discarded like a used plastic bag and the bones picked clean. What it really reminded me of was the movie “Cocoon” when the aliens discarded their human skin to show the old people their true selves. Over the course of the rest of the week that we were at the Palo Verde station, I saw dozens more disemboweled Cane Toads, and it never ceased to be a strange sight. One night, a group I was not a part of went hiking just as the rain began and saw a Cane Toad dragging itself along by its two front legs because its back legs had had the flesh sucked from them by a predator and they were now useless. I imagine that something, likely an opossum, either finished it off or it crawled into the tall grass to die.

When I got back to the field station. I showed one of the professors the picture and he said that because the frogs here have such toxic skin, the animals have evolved to flip them onto their backs and remove the meat through the belly so as never to touch the skin. Indeed, even after this they still refuse to eat the skin and instead leave it to the snakes. I found that super interesting. Imagine if the Australian fauna evolved to turn Cane Toads inside out, I’m sure that’d solve most of Australia’s problems right there. Buuuuut, on the other hand if they did catch on to that strategy we might not have the “Cane Toads: An Unnatural History” video so I’ve got some mixed feelings.

Finding dead reptiles or amphibians is usually not a common occurrence for me, largely because I live in a heavily fragmented area and reptiles and amphibians are no longer nearly as common as they were when I was in elementary school. Walking outside and seeing the evidence of thriving predator-prey relationships was pretty neat; usually the only deceased amphibians I find are killed my cars and there aren’t any interesting observations to be made. In the ripped body of one of the Cane Toads I observed later in the week was the partially digested body of a snake. I can only imagine that it must have been one upsetti spaghetti.