Research Experiences for Undergraduates in Tropical Biology in Costa Rica June 15 to August 22, 2008

What is the program like? Why work at La Selva Biological Station? What are the program requirements? Who can apply? What does the REU award cover? What are the program dates? Application Instructions More information List of Mentors FAQ's See 2004 Student Projects Orientation Material (PDF) Mentors OTS REU Summer 2008 OTS is seeking additional mentors for the NAPIRE program. CLICK HERE for more information. Mentor Contact info Research interests Dr. Alex Gilman Finca Los Nacientes, La Virgen de Sarapiquí, Costa Rica alexgilman @ yahoo.com arbuscular mycorrhizal fungi, plant physiology, global climate change More info Dr. Tom Goldschmidt University of Karlsruhe, Karlsruhe, Germany tomgoldschmidt @ web.de water mites, water quality monitoring More info Mirjam Knoernschild University of Erlangen, Erlangen, Germany knoerri @ gmx.de animal communication, behavioral ecology, bats More info Susan Letcher University of Connecticut, Storrs, CT, USA susan.letcher @ uconn.edu susan_letcher @ hotmail.com plant succession, seedling ecology, lianas More info Dr. Markus Metz Freelance conservation biologist and GIS analyst, Erlangen, Germany markus_metz @ gmx.de animal communication, behavioral ecology, birds More info Nicole Michel Tulane University, New Orleans, LA, USA nmichel @ tulane.edu understory bird populations, conservation biology More info Dr. Ralph Saporito Old Dominion University, Norfolk, VA, USA ralph.saporito @ gmail.com aposematism, chemical defense, poison frogs More info Marcía Snyder and Dr. Catherine Pringle University of Georgia, Athens, GA, USA slothactionhero @ gmail.com stream ecology, biogeochemistry, freshwater crustaceans More info Steven Whitfield Florida International University, Miami, FL, USA steven.whitfield @ fiu.edu amphibian declines, conservation biology More info Dr. Bill Eaton Peninsula College and the Center of Excellence, Port Angeles, WA, USA Bille @ pcadmin.ctc.edu microbial ecology and biodiversity More info Cynthia Rossi La Selva Biological Station GIS Lab Manager crossi @ sloth.ots.ac.cr Rainforest landscape, Geographic Information Systems (GIS), satellite imagery, land cover change, forest fragments, predictive models, and spatial analysis. More info Steve Yanoviak Universityof Arkansas, Little Rock, AR, USA spyanoviak@ualr.edu ants, behavioral ecology More info Mentors’ Project Ideas for REU 2008 Dr. Alex Gilman Finca Los Nacientes, La Virgen de Sarapiquí, Costa Rica Project description: Arbuscular mycorrhizal fungi acquisition in cuttings of tropical rainforest plants Approximately 96% of angiosperms have positive mutualist associations with arbuscular mycorrhizal fungi (AMF). Mycorrhizal fungi help plants to obtain essential nutrients, and are located in or around plant roots. Plants in the family Rubiaceae (Coffee) have AMF associations, but we know little about the rate at which new cuttings, used for experimental research, acquire AMF, or how the amount of AMF present compares to the populations established on adult plant roots. This project involves making plant cuttings, field collection of roots, (for adults and cuttings planted near adults), laboratory staining of root material and the identification and quantification of AMF structures under the microscope. Although I am proposing an AMF project, I'm actually a plant ecologist/ biogeographer/ plant macrophysiologist/soil ecologist and can be totally flexible in modifying or generating new project ideas if there are no students as excited as I am by Arbuscular Mycorrhizal Fungi! I also have a lot of physiological equipment at La Selva that could be used in a student project looking at temperature impacts on leaves and how climate change might impact forest species, which I investigated for my Ph.D. research. Back to top Dr. Tom Goldschmidt University of Karlsruhe, Karlsruhe, Germany Project description: Water mites (Acari, Hydrachnidia) as indicators in tropical springs The overall framework of the project is the development of a ‘water-mite-based’ spring typology as basic tool for long-term monitoring and management of tropical springs. The project at La Selva includes the following aspects: morphological and physico-chemical classification of different springs; collection and determination of watermites and other invertebrates in springs and streams; description of typical water mite assemblages of springs and streams at La Selva; comparison of the diversity of different habitats; clustering of springs according to these assemblages; comparison of these clusters with “morphological” spring types and physico-chemical differences; defining ‘water-mite-based’ spring types. For the student, some previous basic knowledge on freshwater invertebrates would be helpful, but is not mandatory. Most important would be the student’s interest and ability to work carefully on very small animals (0.5-2.0 mm), to conduct thorough field work and to hike (slightly) longer distances (we would collect in as many sites as possible, not being limited to the direct vicinity of the lab). The student would learn how to collect, preserve and determine freshwater invertebrates (especially water mites); get an inside view into water mite taxonomy; would learn how to address to ecological questions by field studies and classical taxonomic work and how physico-chemical and structural differences interact with faunistic differences at a small local scale. She/he would join an exciting ongoing research project and help to work out the baseline for important long-time monitoring projects also at a larger regional scale. According to the available time and interest, we could also start the detailed taxonomic work on the collected water mites (slide mounting, drawing, species-determination, differentiation of morpho-species) as most probably about 70-80 % of the species would be undescribed. Back to top Mirjam Knoernschild University of Erlangen, Erlangen, Germany Project description: Social behavior during ontogeny - are there sex-specific differences? Students working with me can study aspects of the social behavior of Saccopteryx bilineata, a bat species belonging to the family of Emballonurids (sac-winged bats). In La Selva, seven species belonging to this family are found and S. bilineata is the best studied of all. The complex social behavior exhibited in the day-time roosts of this species consist of elaborate visual, acoustic and olfactory displays. In a descriptive approach using behavioral observations (video-taping and time-budget analysis), the sex-specific differences of various behavior types can be studied. In particular, I am interested if the occurrence of behavior types that in adulthood are male-specific (e.g. male courtship behavior with hover displays and odor fanning) is already sex-biased during ontogeny; this would suggest that important parts of the adult behavioral repertoire need to be acquired or practiced during ontogeny. Apart from learning how to observe animals and describe their behavior in a scientific way, the students can acquire techniques to handle wild bats (capturing, identifying, and banding). In the latter case, an anti-rabies inoculation is necessary. Students who want to work with me should be highly motivated, comfortable with working alone in the forest (during the day) and patient as well as accurate observers. Back to top Susan Letcher University of Connecticut, Storrs, CT, USA Project description: Liana seedling dynamics and habitat preferences Lianas (woody vines) are a major component of tropical forests, and affect forest development in many ways. I am interested in the interactions between lianas and other woody plants during forest succession. Possible projects include 1) revisiting a mapped population of liana seedlings to follow their survivorship, and examining factors which may influence their distribution; 2) mapping the way that liana shoots of different species explore space; or 3) studying the physical environment of liana seedlings (light levels, temperature variation, etc.) to investigate whether certain species are habitat specialists or generalists. This project will involve lots of field time. Students who are interested in working with me should be self-motivated, mature, and capable of working independently in often uncomfortable field conditions. Interest and experience in working with plants is a plus. Back to top Dr. Markus Metz Freelance conservation biologist and GIS analyst, Erlangen, Germany Project description: Breeding biology of Montezuma Oropendolas The Montezuma Oropendola (Psarocolius montezuma) offers several opportunities for an undergraduate student participating in the REU program. Montezuma Oropendolas are large birds with conspicuous behaviour, acoustically as well as visually. They breed in colonies in isolated trees, often in forest clearings where many nests are built close to each other. Their nests are unusually large structures, probably adapted to predator avoidance. Males engage in conspicuous courtship behaviour, a combination of acoustic and visual displays. One possibility for a project would be to investigate differences in males with respect to their courtship behaviour using video recordings and sound analysis techniques. If matings can be observed, details of courtship behaviour can be identified that are related to successful matings. The considerable difference in size between male and female Montezuma Oropendolas suggests that males are subject to extensive sexual selection. There are a number of reasons why certain bird species breed in colonies whereas other bird species place their nests solitary and often well hidden. Another possibility for a project would be to record details of the colonial breeding behaviour of Montezuma Oropendolas and compare the results with literature on other bird species breeding in colonies. The aim will be to identify selective pressures that lead to the formation of colonies in Montezuma Oropendulas. Back to top Nicole Michel Tulane University, New Orleans, LA, USA Project description: Foraging behavior and habitat choice in the white-breasted wood-wren (Henicorhina leucosticta) Rainforest understory insectivorous birds have undergone recent and significant population declines at La Selva Biological Station, potentially due to mechanisms such as food limitation, and loss of preferred microhabitat. However, one little-studied species, the white-breasted wood-wren (Henicorhina leucosticta) has increased at La Selva, while disappearing from Barro Colorado Island, Panama. I propose that the student locate H. leucosticta territories, conduct foraging observations to identify dietary preferences, and collect habitat structure data on multiple territories. This habitat data can then be compared with data collected by me at random points at La Selva to determine microhabitat preferences of this species. Back to top Dr. Ralph Saporito Old Dominion University, Norfolk, VA, USA Project description: Aposematic coloration in the strawberry poison dart frog (Oophaga pumilio) My research interests surround the ecology and evolution of chemical defense and aposematism in poison frogs. I am currently very interested in understanding the factors that influence the effectiveness of aposematic signals in dendrobatid poison frogs. Brightly colored dendrobatids are chemically defended from predators by the presence of toxic alkaloids. Although it has long been assumed that bright colors function as a warning (or aposematic) signal to predators, this has only recently been demonstrated. By using clay frog models, my previous students and I have provided experimental evidence suggesting that bright coloration in the dendrobatid frog, O. pumilio, functions as an aposematic signal. Clay model experiments have also been used successfully to study aposematism in snakes, newts, and millipedes. Oophaga pumilio is the most abundant dendrobatid frog at the La Selva Biological Station and is an excellent model organism for studying aposematism in dendrobatids. Potential Research Questions: (1) On the basis of my previous work, there is some evidence of differences in predation and therefore effectiveness of the aposematic signal in O. pumilio among different habitats. Therefore, a potential project is to further examine the effectiveness of the aposematic signal in O. pumilio among habitats at the La Selva Biological Station. (2) Aposematic signals are generally being expressed to visual predators. Therefore, it is important to understand how other factors aside from color influence the overall signal. On the basis of my previous work, there is some evidence that frog model shape is important to predators. Therefore, a potential research project would be to examine the importance of frog model shape, size, and form as it relates to aposematism in O. pumilio. How accurate in shape, size, and form do the frog models need to be to deceive predators? (3) Although aposematism is generally thought to only involve a color signal, pattern also plays an important role. In addition to being brightly colored, O. pumilio also contains patterning in the form of spots. Therefore, a potential research question would be to address the importance of pattern in the aposematic signal of O. pumilio. Back to top Marcía Snyder and Dr. Catherine Pringle University of Georgia, Athens, GA, USA Project description: Freshwater shrimp populations and stream water chemistry I study the effects of water quality both natural variations e.g. geothermal seeps and pollution e.g. agrochemicals from banana production on shrimp population dynamics. Fifteen species of freshwater shrimp occur in Costa Rica; seven on the Caribbean side. These crustacean decapods play a key role in food web stability and nutrient cycling. In addition to the vital role they play in aquatic ecosystems, freshwater shrimp are also commercially important as a food resource. La Selva streams occur across a natural phosphorus (P) gradient with the high P streams receiving input from geothermal springs. In times of low precipitation these geothermally influenced streams maintain a higher pH whereas the non-geothermally modified streams experience sharp drops in pH (~4.5). I am interested in determining if shrimp populations in forested pH-buffered streams exhibit differences from unbuffered streams in terms of abundance and size of shrimp populations. A number of areas exist where an undergraduate student could contribute. A few questions include: (1) how does shrimp fecundity differ between pH-buffered and non-buffered streams? (2) does shrimp microhabitat usage differ between pH-buffered and non-buffered streams? (3) is there differences in resource quantity and type as well as resource quality between pH-buffered and non-buffered streams? Back to top Steven Whitfield Florida International University, Miami, FL, USA Project description: Identifying drivers of amphibian population declines Declines in amphibian populations represent a global problem in conservation biology. In the past three years, I have worked as part of a research team that has identified widespread population declines in all species of amphibians from La Selva, and parallel declines in ecologically similar species of small lizards. My current research investigates processes that may contribute to these declines: habitat fragmentation, invasive pathogens, pesticide inputs from nearby agricultural areas, and climate change. Students who work with me would investigate some aspect of conservation risks to amphibian and reptile populations at La Selva. Any project is likely to involve extensive field sampling of amphibians (and perhaps reptiles as well) using standard methods, and students will be expected to learn to identify a large number of amphibian species, including members of some challenging groups. Here are three sample project ideas: 1) One project idea is to look at species diversity and composition of pond frogs across a disturbance gradient. There are a number of swamps or temporary ponds at La Selva that have many species of frogs in them. Some of these swamps are in pasture, some in disturbed secondary forests, and others in closed forest. It would be possible to compare species diversity between the land-use regimes to see which species are tolerant to disturbance. This would be a reasonably straight-forward project with easy data collection and strong conservation implications. It would also be possible to compare survival and growth rates of tadpoles in enclosures in various types of ponds. 2) Another project idea is to explore the effects of forest-pasture edges on amphibian and reptile communities at La Selva. In the past four decades, much of the land surrounding La Selva has been cleared of trees and converted to pastures. Many studies have shown that effects of pasture can extend several hundred meters into forest where there are edges, changing abiotic factors and amphibian communities. It would be possible to examine the impacts of "edge habitat" between forest and pasture, to understand how far effects of habitat surrounding La Selva extend into the La Selva Reserve, and which species are most affected by these edges. 3) Pesticides are widely used in agricultural areas around La Selva, and these pesticides can be transported long distances by wind, ending up in protected areas like La Selva. We don't understand the impacts of these pesticides on tropical amphibians, but rather straightforward methods exist to gauge the impacts of these agrochemical compounds and tadpoles. Back to top Dr. Bill Eaton Peninsula College and the Center of Excellence, Port Angeles, WA, USA I am interested in microbial diversity and nutrient levels in both aquatic and terrestrial habitats. Microbial ecology is expanding rapidly due to the application of molecular biology-based technological advances. The astounding diversity of microbes across different habitats allows us to ask multiple questions about the relationship between habitat quality and biodiversity. Moreover, variations in microbial diversity (and/or community structure) is starting to be examined as a potential indicator of habitat change. Some possible projects include: examining specific microbial biodiversity in different habitat types within aquatic and terrestrial habitats; examining broader microbial community structure within these habitats and linking it to mineralized carbon and nitrogen levels, efficiency of carbon utilization and microbial growth, and nitrogen cycling rates; examining these parameters in some specific and ecologically critical habitats, for example, “leguminous” nodulated trees vs non-nondulated trees; examining these parameters as potential indicators of improving soil habitats in the reforestation efforts in the San Juan – La Selva Biological Corridor photosynthetic biomass in soil or water in relation to photosynthetic microbial diversity, chlorophyll biomass, nutrients Since very little microbial work has been conducted at La Selva, the field is wide open. Back to top Cynthia Rossi La Selva Biological Station, GIS Lab Manager The study of interactions between different cartographic layers or particular biodiversity hotspots within northeastern Costa Rica using GIS and GPS tools is critical for analyzing the landscape ecology of the region. My interests lie in using spatial analysis using GIS data (such as radar, LiDar and/or other satellite imagery, soil, climate and land cover data) to map current land use regimes in the tropical rainforest landscape at La Selva. One idea would be to work in the San Juan La Selva Biological Corridor to study forest fragments by using GIS science to determine tree density for particular species, such as Dipteryx panamensis, in areas that have not been well studied. A student would have the opportunity to use remote sensing and GIS techniques to determine species density and composition. Field work would be necessary to validate the models. Other potential projects may also include topics such as predictive modeling to determine sediment loading in the rivers or mapping canopy gaps using LiDar imagery as it relates to such factors as climate change, etc. Back to top Steve Yanoviak Universityof Arkansas, Little Rock, AR, USA My research focuses on the behavioral ecology of ants in the tropical forest canopy and leaf litter. There are over 450 ant species at La Selva, inhabiting a wide variety of habitats and ranging in size from less than 2mm to 25mm. How do all these species coexist? How does habitat use vary among species? Body size influences the way that arthropods perceive and react to their environment. According to the size-grain hypothesis, as the size of an organism decreases, the perceived complexity of its habitat increases. Substrates such as moss, tree bark, and vines provide different levels of connectance and negotiability depending on the body size of the insects crossing them. Interspecific interactions among ants may vary depending on the substrates that they use. Students working with me will likely use experimental approaches to examine the effects of substrate characteristics and connectance on interspecific interactions among ants. More information about my work can be found at my homepage. Back to top