Conclusions from the Course

Cabo Blanco was mostly about wrapping up papers and having some great end-of-course parties and gave me the opportunity to think on all that I had learned over the this month experience.

I have shared with you so far much of the beauty and intrigue, large and small, of the sites we visited. But in my work and education in conservation, there was much to contemplate beyond an introduction to and appreciation of natural Costa Rica. So, along those lines, here's a smattering of impressions and ideas that struck me...

From a technology perspective, some obvious conclusions emerged. GPS: not there yet and not clear how we get there any time soon. The devices are fine, it's the canopy that's the problem. So unless you can afford an antenae to get your reading above the trees, GPS is just a nice idea. Devices in general, including field text, audio, image and video collection, are coming down in price, but under used by researches because those with sufficient durability are still prohibitively expensive. It rains a ton and if your device isn't waterproof, it's rather useless. Moreover, the degree that technology determines the scope of research projects was clarified. That is, researchers use the tools they know and answer the questions their tools can illuminate. It's easy to see how specialized technology is playing an increasingly important role in biology: gene research being the most striking example. But GIS was rarely used in our course, not because there weren't innumerable fascinating spatial questions to ask and answer with GIS, but because almost all the students lacked familiarity with the toolset. That will change as the tools improve (dramatic improvements await!), but I was struck by the lack of use even among these young and sophisticated computer users. It's nice to be needed. Finally, I continue to see an opportunity for dramatic new organization and infrastructure in bioinformatics. The combination of incredible information overlap, in real data not just metadata, combined with powerful scientific and conservation implications for effective sharing means that there are huge untapped efficiencies. I continued to be inspired by the idea of a sub-internet, a "Bioinformatics Web" where conservation and scientific, especially conservation biology, data is entered, analyzed and leveraged in dramatically improved ways. Bottom line on this topic is that my work at NatureServe seems just the right thing.

As I said in my Conservation Economics post, I was moved by the irony of Costa Rica's acclaimed conservation programs and the realities of continued deforestation. Amphibian declines and ongoing hunting issues clarified the possibility of "empty forests". Secondary forests may indeed be the forests of the future, but if biodiversity declines continue, they will be characteristically quite different.

But it was the economic realities of conservation that I was most impressed by, specifically the need to develop the economic rewards of conservation and reforestation or be prepared for continued degradation. For instance, I was compelled by our discussion with Dan Jansen's and his bias against species-based conservation at the cost of simple acquisition and effective protection of intact landscapes or those suitable to reforestation that can connect intact landscapes. His views were characteristically harsh, but pragmatic. Dan also spoke with us about the accessibility that DNA bar coding may bring to non-scientists. I happen to agree that taxonomy need not be protected by the high-priests of today's taxonomists and that they is enormous education, and conservation, potential in making species identification increasingly cheap and easy.

Here again the theme of integrating local people into the conservation/restoration theme was clarified. Dan's work under INBio to train and employ local experts in taxonomy is a powerful alternative to the traditional, first-world-academia approach used by many conservation organizations. We saw another example the power of local knowledge in Cuerici where Swiss foresters controlled "sustainable forestry" practices. Secondary tree mortality resulting from the selective logging was much higher than the experts anticipated but completely consistent with the predictions of local farmers who know the forest.

In getting to know my fellow students, I was impressed and heartened by their talents and passion for their areas of expertise. I look forward to watching many of them progress to successful careers in science. I was surprised, I must say, by how some of the brightest minds among them seemed relatively unconcerned by issues in conservation. If nothing else, I would think self-interest in the preservation of their own systems would motivate some concerns. The course coordinators' inclusion of conservation and social science issues was thus all the more valuable to me.

I was also struck by the need for environmental education to encourage pragmatism and a system's approach. Even some faculty members took what I considered to be idealistic and unrealistic positions on the case for conservation that simply ignored historical, sociological and economic forces that must be respectfully confronted. In others I witnessed extreme pessimism about those same forces and a sense of helplessness. Both classes of response were recognizable to me from my own history. My experience in Costa Rica has clarified for me at a deeper level the need to stay positive, constructive and holistic in my own thinking and communication. Neither narrow idealism nor pessimism can be afforded.

There were some side lessons on leadership. My course coordinators struggled a bit to maintain good science content and keep logistics in order. Without going into too much detail, I can say that the course provided a small microcosm for the study of leadership and group dynamics. I didn't envy the coordinators' leadership challenges especially logistics in a foreign country and a bunch of opinionated students with sometimes conflicting needs. The experience gave me countless examples of the idea that leadership is best thought of as service ... and hard work. I particularly emphathized with the lonliness that leadership can sometimes bring, specifically the need to let go of being understood and even liked.

In these blog entries, I can see an evolution in my understanding of Costa Rica, natural systems and tropical biology research. What I will remember about Costa Rica is the combination of its natural beauty and conservation realities. What a fantastic and fun (!) experience.

Swimming at Cabo Blanco

As a fitting end to our two month course, we went to the beach. Cabo Blanco is a secluded reserve on the southwest corner of the Nicoya penninsula where the forest meets the ocean. We spent four days at this beautiful site here doing our final field work. The snorkeling was fantastic and gave us a great opportunity to do underwater research projects.

My team worked with James ("Jimmy") Liao from Harvard's Department of Organismic and Evolutionary Biology. Jimmy has done some amazing work (cover of Science Magazine!) showing how fish optimize their swimming motion by slalmoning through areas of turbulance in streams. They change the cadence of their swimming strokes to 'bounce off' regular eddies or vortices caused by obstacles or other fish. In doing so, they use much less energy versus a normal swiming stroke.

Jimmy worked with our team looked to explore another (simpler) aspect of swimming biomechanics: fish morphology and potential correlation with habitat types. Paul Webb in 1984 proposed a "functional-morphology plane" that describes fish as cruisers (think tuna), maneuverers (think angel fish) or accelerators (think grouper) or some combination of the three.

We categorized the fish just off shore from Cabo Blanco as one of the basic three types and tested for coorelation to two different habitats: one closer open ocean and the other more protected and spatially complex. We did find a correlation between cruiser morphology with the habitat closer to open ocean and also between manueverer morphology and the more protected and complex environment. The project gave us some interesting exposure to concepts in evolution and specialization in the context of marine environments.

Conservation Economics

Monteverde's cloud forest is truly sublime with its distinctive dripping moss. The area has become one of Costa Rica's most famous destinations for ecotourism. In ironic support of that purpose, it's extremely hard to get to: the dirt road is long and jaw-crushingly filled with pot-holes. By this "neglect", the town of St. Elena and the Monteverde Reserve are discouraging day trippers from San Jose. You have to want it; you must commit. And if you do you'll spend more money and speak more favorably of it to your (wealthy) friends.

Founded by Quakers from the US in 1951, early ideas about ecotourism and its ability to make the economics case for conservation were developed here. Unlike most of Costa Rica's protected areas, the Monteverde Reserve itself is privately owned. In order to protect both the forest and visitors' experience of it, the Reserve limits visitors to 120 at a time into this 10,500 hectare property. The price of admission is $12, steep compared to most protected areas, but my sense is that travelers, especially Americans and Europeans, would pay more.

But should Costa Rica convert its economy to ecotourism? It's not an easy argument. Much of Costa Rica may not be interesting to tourists. Small rural communities, pastures, farms: these are not the places tourists flock to. Moreover, compared to agriculture or ranching, tourism is ephemeral. An international economic crisis renders a tourist economy vulnerable whereas the need for cows, banana, pineapple, rice and sugar cane remain.

Over the course of this trip, the irony of Costa Rica has become clear to me. Hailed as a model country for ecotourism, deforestation continues. Celebrated for its visionary park system, most of the parks are inadequately staffed and aren't valued by their surrounding communities. Traveling this landscape, dominated not by forest but by pasture and farms , it's hard not to see that assigning existence value to primary forest is a luxury of the wealthy. Since most of Costa Rica is accessible, even if by crappy roads, every parcel of forest that does remain must justify itself economically to those that own it, manage it and live on or around it. We're closer to the situation in which every tree persists because someone decided it makes some economic sense for it to do so versus a belief in its value as habitat (for monkeys, ants or birds) or its inherent tree-ness.

We spoke with some folks with Fundacorps, a sustainable forestry initiative sponsored in part by World Wildlife Fund, while at La Selva. From those discussions, it became clear that Costa Rica's carbon credit system isn't financially competitive with most other land uses. Furthermore, it's possible to log a forest and then invoke the carbon credit system for several years, then, when you're ready to harvest more trees, turn it off again. That may work well for sequestering carbon, but it doesn't incent the preservation of primary forest and all the biodiversity therein.

At as for the value of biodiversity itself, Merck Pharmaceuticals invested heavily in the protection of biodiversity in Costa Rica to enable "bioprospecting": the mining the forest for tomorrow's chemical compounds. As a consequence, INBio, Costa Rica's national biodiversity institute, was funded to inventory the nation's biodiversity. But Merck's investment didn't pay off. Productivity from synthetics research in the lab outstripped that of the primary forest. Merck has withdrawn most of its funding and INBio now struggles to stay viable.

For those who do see value in the forest's existence, the task is clear: find real economic value that actually pays the bills. That may be ecotourism, carbon sequestration or more abstractly insurance against catastrophe (similar to a diversified financial portfolio, a diverse species portfolio increases nature's chances of recovering from or avoiding disaster). But the value must be real and turn into hard currency for those who have the fate of conserved lands in their hands: local communities, local governments.

Monteverde

2nd to last stop: Monteverde Biological Station. The cloud forest was beautiful, the weather was refreshingly cool and the local economy provocative for me about the viabiliy of ecotourism as a way to sustain biodiversity. The station has excellent trails up into the cloud forest and the Monteverde Reserve (photo above with Jimmy in awe) was easy to get to. A wild hummingbird exhibit was just next door to the reserve.

Yet what most struck me about Monteverde was what I didn't see: frogs. We were joined by Allesandro Catenazzi, a professor of herpatology so I was excited to do more work with frogs. But as I mentioned in the posting on our Dendrobates Pumilio project, the amphibian decline has hit all of Central America hard, especially the montane forest species. So my hope of trapsing along streams to find these little jewels of nature was thrwarted, probably by the chytrid fungus.

I did, however, get a chance to visit the somewhat artificial but deeply rewarding Monteverde Frog Pond. This collection of large terrerariums hosting mostly lower montane species gave me satisfaction of seeing these marvelous creatures, even if not in their natural environment.

While I'd love to claim credit, the photo above was taken by a previous OTS student, Ingrid (didn't get a last name). This is Agalychnis callidryas, the red-eyed tree frog. It's actually doing quite well comparatively. The Global Amphibian Assessment ranks it as "Least Concern."

Rincon de la Vieja

During our stay at Palo Verde, we took a day off. First day off in six weeks. Folks were getting cranky. So the coordinators organized an excursion to Rincon de la Vieja, "haven of the old woman", a volcano about two hours away. It was a magnificent hike to the top of the volcano that began in one of the most beautiful primary forests I saw in all of Costa Rica. In this first picture, Maya, myself and Cynthia take a moment to mock the "Pirate's Code", that is, "if you can't keep up, you'll be left all by your onesees."

Of course, we all made the hike easily. I'll leave it at that and let the pictures below tell the rest of the story.

My sense of scale wass thrown by the intensely clear air, long vistas and surreal landscape. For instance, those little dots on the left rocky ridgeline are fellow hikers

The mouth of Rincon de la Vieja

Palo Verde

In the northern province of Guanacaste, the Palo Verde Biological Station sits just above an extensive marsh. The Tempisque river runs through the marsh and low mountains border all sides. We were warned of intolerable heat and mosquitos in this tropical dry forest, but I found neither particularly bothersome (at the time our of our visit, much of the US including DC was suffering an intense heatwave: I think we were much more comfortable than our friends back home). I was delighted by this station, perhaps because of the familiar dryness to my home state of New Mexico, but moreso because of its remoteness and extensive natural vistas.

We were joined at Palo Verde by Xavier Basurto, a social scientist working on conservation from the University of Arizona. Xavier works on community-based management of natural resources, an approach that I find both practical and heartening. I was so inspired by his description of the theory and framework for successful community management of common pool resources that I commondeered another student, Michelle, to work with me on an independant project to apply the principals to water management issues in the Tempisque River Basin. While the scope of our project was too small to allow a thorough examination of the the issues, it was a valuable excercise and one that I hope to pursue in other venues, both because of the importance of fresh water as an increasingly scarce resource and because of the justice and practicality I sense in the community managment approach.

On a walk to the river one day, we came across a troupe of howler monkeys lazily eating fruit from the trees over our heads. Here's one sunning himself, letting mango digest.

Black Mangrove

On route from La Selva to the Palo Verde Biological Station, Jorge Jiménez, the director of OTS, joined us for an excursion into his research system: Costa Rica's black mangrove forests. Living at the intersection between salt water, land and sometimes fresh water, mangroves find their niche by adapting to the challenges of salt, flooding and toxins. In the picture below, you can see the trees' pneumatophores rising out of the ground like spikes. These appendages to the root system take in oxygen in the context of submerged soils. When completely flooded, black mangroves effectively "hold their breath" and have finite capacity to do so.

Mangrove vegetation occurs in 'zones' and in our short walk, the vegetation dramatically changed. We followed Jorge out to the submerged areas of the forest, discovering our inner primates while climbing across the elevated roots seen in this picture below.

Tropical Forests = Carbon Source?

In the CO2-cycling machine planet Earth, tropical forests are on our side. Scientists have been telling us that climate change, caused by fossil fuel emissions, is mitigated by CO2 uptake of plants in the process of photosynthesis. But plants also emit CO2 in the process of respiration. Researchers at UC Davis recently reported that respiration appears to be essential to the growth of plants, perhaps in order to convert nitrate into a usable form, nitrogen. So when we talk about tropical forests as a sink for CO2, we're really saying that they absorb more CO2 than they emit. But under what conditions might this balance change?

My teammates on our "Biomass of Lianas and Trees" project
at La Selva, the site of Debra Clark's research

Debra Clark spoke to us one night about her research on long term tree growth at our host site, the La Selva Biological Station. It was a fascinating and rather disturbing talk where she emphasized the preliminary and unconfirmed nature of her findings ("Hubris, man!" was her call to scientists and politicians alike). Results from the TREES project show slower growth in years with higher temperature and decreased rainfall and that in the same time periods forests may have been overall sources, not sinks, of CO2. With increased warming and drought forecasted for the tropics, the result is that forests may actually contribute to climate change in a positive feedback cycle. At risk of sounding like Debbie Downer, the feedback cycle could be further exacerbated by increased fire and tree mortality.

Again, Clark's findings are highly preliminary, but we can say that the role of tropical forests in offsetting anthropogenic emissions is unclear. Based on what we do understand, the conservative course of action is clear: get moving! Change our priorities and create the economic incentives sufficient to end deforestation and dramatically curtail fossil fuel emissions.

Origins of Flight, Mean Ways to Fight

Besides leaf cutter ants, we’ve been introduced some of the, ahem, totally cool biomechanics of certain ant species. For instance, Robert Dudley from UC Berkeley gave us a lecture on flight mechanics. That’s right: flying ants. Think about it: arboreal ants (them that live in trees) can easily fall long distances from the branches of canopy and when they do, will they fall to their deaths or will they have evolved the ability to control their decent. Indeed, flying hind legs first many ant species not only control their decent but effectively steer a landing on the truck of the tree from which they fell and simply walk back up the tree to resume their activities. Wow. A collaborator has video footage of the gliding ants at this site. Such controlled decent is found in many species and researchers now hypothesize that the origins of flight began not from the ground up but instead from the high branch down. The hazard of falling from trees thus may have spawned the evolution of flight.

Our own Andy Suarez, who happens to be a lot of fun, has done some interesting research into another area of ant biomechanics: "trap jaw" ants. These are ants that sport huge mandibles spring loaded to close at a rate of 50-60 meters/second. That's the fastest motion known in nature. Trap jaw morphology as evolved at least five times in ants, the most famous being the genus Odontomachus. Not only used to capture and crush absolutely helpless prey, trap jaw ants have been shown to use their unique abilities to escape attack. An ant in despiration will place their mandibles against the ground and fire the release which, because of the enormous force in comparison to their body weight, hurles them into the air and, if all goes well, out of harms way. Andy showed us some truly amazing slow motion video of this last phemonmeon. His collaborator's web page has more infomation if your interest is peaked.

Roxanne

To put it midly, these are interesting times for frogs, toads, salamanders and caecilians. On a global scale, amphibians are in decline. My own organization, NatureServe, was involved in an international effort to assess the state of amphibians and the news was not good. Nearly one-third (32%) of the world’s amphibian species are threatened, representing 1,896 species. By comparison, just 12% of all bird species and 23% of all mammal species are threatened. As many as 165 amphibian species may already be extinct. In Central America and other regions, frog species in particular are being devastated by the chytrid fungus. At the same time, La Selva as a site plays hosts to impressive amphibian diversity and as a biological station has a long history of amphibian research. So it seemed appropriate to direct one of my independent research projects while at La Selva to some investigation into frogs, these gems of species, this "charismatic microfauna."


I interested another student, Anna from the University of Indiana, in the idea of studying Dendrobates Pumilio, one of the poison dart frogs. D. Pumilio is a wonderous species: besides the beautiful red and blue coloring, they exibhibit interesting reproductive behavior. Males establish territories and call females to them with a distinctive “eh eh eh eh eh eh” sound. Males actively defend their territory against males of the same species first by issuing an “encounter” call distinctive from the mating call and, if the intruder isn’t deterred, engage in physical combat. The resident male usually wins the battle and the territory is his. After mating with a male, the females lay eggs in the forest leaf litter. Males have been shown to guard the eggs until they hatch, afterwhich one of the parents will carry each tadpole on its back to a separate bromeliad plant high in the tree canopy. At this point, female returns daily to lay unfertilized eggs as food for the growing tadpole.

Anna and I decided to conduct an experimental study on the communication mechanisms of D. Pumilio, auditory, visual and behavioral. Our species was easy to find at La Selva as males continuously announce their presence in form of mating calls and of course distinctive coloration makes both males and females relatively easy to spot. As part of the territory defense, we hypothesized that males would respond first to the sound of a competitive male intruder, then to its image and finally to signs of aggressive behavior. Seems pretty intuitive, sure, but this is OTS and we only have a few days to design, execute analyze and present our study. To test our bold idea, we needed to separate these communication mechanisms and compare them individually and in various combinations. Our plan was to choose an actively calling male and present him with one of these combinations of simulated sound, image and interactive behavior and measure his responses.

For sound, we started with recordings of the mating call of a few sample males and an encounter call we downloaded from the web, combining them into a single hour long recording. Ours would be a frog with endurance. Lacking a better playback device, we took a course laptop in a plastic bag with us into the field (shhhh!). For image, fortune smiled upon us: another study was going on at La Selva into bird predation on our same species and that team gave us some clay models that gave a pretty good visual impression of a single individual. And finally for behavior, we used a small mirror, the idea being if the sound and image pulled a resident frog in, we could observe the frog interacting with its own dynamic image. We conducted a total of 14 different tests of around 15 min each with various combinations of image, sound and the mirror and measured responses from the resident male.

The first thing we learned is that frog habitat makes for excellent mosquito habitat: we donated a lot of blood while trying to stand still for 15 minutes at a time. That aside, our much basic hypothesis seemed to be valid. The most successful configuration in terms of generating responses was that of sound combined with image followed by sound alone. In one particularly exciting instance involving both sound and image, the resident male approached the model and circled within a few centimeters many times, returned the (more aggressive) encounter call, and seemed “puff” itself up by standing taller on its front legs when approaching our clay model. Our sample size was too small and results to varied for our study to be taken seriously, but it helped us develop an interesting protocol on which a more complete study could be based.

Finally, we found a cool program on the web that proported to provide semantic translate D. Pumilio calls. We ran some our recordings through the program and found an interesting section in which the translation came out as this: “eh eh eh eh, eh eh eh eh ... Rooooxane. You don’t have to put on the red light….” That joke might not work well here on my blog, but it killed in our final presentation to the course.

Here's a female crawling around on Anna's shirt. Don't worry, their poison is only toxic to small preditors.

This was a delightful project because our subject was so engaging. It was all made bittersweet by the knowledge that this species, like so many frogs, may not be long for this world.

The Ant Farmers

Andy Suarez specializes in biological invasions and ants and this was great news for those of us interested in invasive species as well as members of the Social Insect Mafia: the 4 boys in our group who study ants and bees. Since the course began, the Mafia has been educating us all with the fascinating world of social insects. One of the flagship groups in this world are leaf cutter ants, genus atta and acromyrmex. The more I learn, the better I understand the Mafia’s fascination.

Small leaf fragments seem to creep across the forest floor of their own volition, shimmering in sun flecks. Look closer and you will see that they are being carried by ants vastly smaller than the leaves themselves. In the photo below, you can see them walking near the edge of the sidewalk:

These are the leaf cutter ants and the leaves they carry are not for the colony members but for the fungus they grow deep within the colony nest. In this mutualism, the fungus is fed fresh leaves and other plant material and kept free of pests and molds. In turn the fungus is consumed by the colony. To additionally defend the fungus garden, the ants carry on their bodies a specialized bacteria that produce antibiotics. Leaf cutter ant fungi-culture, including this three-way mutualism, likely evolved over 50 million years ago making it the most ancient form of agriculture known to exist in nature.

If the practice of agriculture doesn’t grab you, try this: a mature leaf cutter ant colony may contain more than eight million members specialized into five primary morphotypes all with specific roles and whose behavior is communally directed. The heavy lifters that cut and carry leaves back to the colony are members of the mediae caste. A closer look at individual leaf fragments will reveal minors riding on the fragments, inspecting them for potential dangers to the colony. Of course this adds to the already considerable load born by the mediae. The trail between food source and colony home can be several kilometers long and is patrolled and maintained by majors, the significantly larger soldier ants. Living out their lives entirely within the colony are the minims that tend the growing brood and are the gardeners of the fungus crop. Finally, there is the single queen who produces the various morphotypes in response to the colony’s requirements as determined by, get this, her diet. It has been shown that the colony will change the content of her diet in response to a deficiency in a particular morphotype. In turn she will produce more of the required type.

The Virtues of Inbreeding

At each site, we’ve been joined by guest faculty members from various institutions. Larry Kirkendall from the University of Bergen and Andy Suarez from University of Illinois joined us at La Selva. I’ll return to Andy’s research in another post. Larry is doing research on the bark beetles of La Selva and gave an intriguing lecture on inbreeding in evolution. Turns out sexual reproduction carries significant costs to a species. The least technical of these including the shear energy it takes to attract, court and mate, exposure to disease, the limited net contribution of males to reproduction and the fact that the most successful genes are always being diluted with less successful genes. Inbreeding (as well as asexual reproduction) avoids these costs. In some bark beetle species, for instance, mating takes place prior to dispersal so the costs of courtship are extremely low. Of course the downside of inbreeding is that genetic weaknesses are passed to all individuals and extremely difficult to overcome. Larry has learned that these bark beetle species, as well as many other species that inbreed, have passed through a narrow evolutionary window wherein their populations found a sufficiently successful gene recipe to enable long term survival in the absence of genetic mixing.

After one or more initial lectures faculty members lead subgroups in field projects in their area of expertise which are in turn presented back to the full group. The result being we are all exposed to the faculty member’s area of expertise from a variety of angles. It’s a great way to learn.