About Our Lab

Long-term Projects  |  In Situ Stream Research  |  Outreach


Long-term Collaborative and Site-based Projects

We are involved in three long-term research projects funded by the National Science Foundation (NSF) and a fourth project that we are pursuing funding to continue:

Both the Luquillo and Coweeta Long Term Ecological Research (LTER) Projects are part of the larger NSF-LTER network of 25 site-based projects across the US. The ecological consequences of land use change and hydroclimatic variability is a convergent theme of both projects. Our studies of stream ecosystems build on a rich history of prior LTER research, made possible by relatively continuous NSF funding over decades (i.e. extending beyond typical 3-year funding cycles) combined with support from the USDA Forest Service. This has resulted in valuable long-term data sets that better inform our research questions. Our collaborative relationship with the USDA Forest Service at both LTER sites has resulted in management applications of scientific research.

Likewise, our Costa Rica STREAMS LTREB (Long Term Research in Environmental Biology) Project, which is funded by NSF’s LTREB Program, has evolved over the decades to pursue new research directions in response to emergent patterns in long-term data: analysis of >25 year datasets on stream solute chemistry and precipitation led us to redirect our research from stream trophic dynamics and phosphorus cycling to the ecological consequences of climate-driven stream acidification.

Finally, the long-term Tropical Amphibian Declines (TADS) Project in Panama examines ecosystem-level effects of the disease-driven extinction of stream-dwelling frogs. This project builds on pre- and post-extinction datasets on stream ecosystem structure and function, providing invaluable baseline data for continued quantification of the long-term effects of an extinction event that removed an entire community assemblage of stream vertebrates.

In Situ Experimental Research in Streams

Our lab has a history of in situ experimental research in streams. We developed an experimental electric exclosure technique to isolate top-down effects of stream macroconsumers (e.g., fish, crayfish, shrimps) on ecosystem properties and processes by excluding them from foraging on the stream bottom (Figs. 1 & 2). This technique results in exclusion of macroconsumers at a local scale, and is particularly effective when combined with (or nested within) reach-scale experimental manipulations. We initially implemented this technique in our studies in Puerto Rico and Costa Rica, and it has since been used in stream studies across the world.

Figure 1. Schematic diagram illustrating electric exclosure technique designed for experimental exclusion of macroconsumers from stream benthic areas (modified from Pringle and Blake 1994).

Figure 1. Schematic diagram illustrating electric exclosure technique designed for experimental exclusion of macroconsumers from stream benthic areas (modified from Pringle and Blake 1994).

Figure 2. Two electric exclosures in study stream, El Cope Panama

Figure 2. Two electric exclosures in study stream, El Cope Panama


Environmental Outreach Activities

Environmental outreach and education have been incorporated into past and ongoing research projects. Examples range from development of posters on riverine biota and connectivity (see posters below) to the development of an outreach program (Water for Life/Agua para Vida) as part of our long-term NSF-LTREB STREAMS Project in Costa Rica.

Click on posters to enlarge

El Yunque and Water

Poster 1: El Yunque and Water: Balancing human water use with environmental needs in Puerto Rico.
This outreach poster illustrates the location of water intakes (sites where water is withdrawn for potable water supplies) from rivers draining the northern part of El Yunque National Forest, Puerto Rico. The poster shows how dams associated with water intakes can act as barriers to the migration of native fish and freshwater shrimps. (GIS work by Dr. John Thomlinson; Development of this poster was made possible from a USDA Forest Service grant to C. M. Pringle and support from the University of Puerto Rico and the NSF Luquillo LTER Project.)

Tropical Island Stream Continuum

Poster 2: A tropical Island Stream Continuum, Puerto Rico: Protect our native plants and animals.All of the native freshwater shrimps, fishes and snails in streams draining Puerto Rico are migratory and must spend part of their life in saltwater. Their migrations form a critical link between stream headwaters and estuaries. However, dams and water withdrawals can block these migrations. A fish ladder (as depicted in the center panel) can help shrimps, fishes and snails migrate past a dam. (Artist: Jessica Mendelsson; Development of this poster was made possible by a USDA-IITF Forest Service grant to C. M. Pringle and support from the NSF Luquillo LTER Project.)

Tropical Stream Continuum

Poster 3: A Tropical Stream Continuum, Costa Rica: Protect our streams.This outreach poster illustrates the connection between the mountains of Braulio Carrillo National Park and the Caribbean Ocean. It depicts fishes and other stream organisms and provides their common, scientific, and Latin names. This poster was created as part of the Water for Life/ Agua para Vida Environmental Outreach Program developed in association with our long-term NSF-LTREB STREAMS Project at La Selva Biological Station. The poster has been distributed to local school children in Puerto Viejo de Sarapiqui and other towns near La Selva Biological Station. (Artist: Jessica Mendelson; Development of this poster was made possible by a grant from the Conservation Food and Health Foundation to C. M. Pringle, and support from the Organization for Tropical Studies)

Forest & Ocean

Poster 4: Forest and Ocean: Working together for us, Kosrae, Micronesia.This poster illustrates the functional connection between the forest and the ocean on the island of Kosrae, Federated States of Micronesia. It was designed for environmental outreach and distributed to children in local schools in Kosrae as well as other islands in Micronesia. The illustration emphasizes native flora and fauna in upland Terminalia swamp forest; interior riverine mangrove forest; coastal mangrove forest; and sea grass beds. Many of the near-shore native fishes, that are important for fisheries, migrate daily between coral reefs, sea grass beds and mangrove channels. The poster shows these migrations as well as the importance of mangrove leaves as a carbon source in these fish-dominated food chains. (Artist: Sarah March; Development of this poster was made possible by funding from the USDA Forest Service in a grant to C.M Pringle.)