Amphibian Monitoring in the Greater Yellowstone Ecosystem
Amphibian populations have declined or disappeared in many parts of the world, including the western U.S. This monitoring project is designed to determine the status and trends of amphibians in Grand Teton and Yellowstone National Parks. Our objectives are to answer the questions:
- Are native amphibian species declining?
- What are the possible underlying causes of any observed declines?
- What further directed research or management actions are warranted?
The monitoring project began as a collaborative effort among the National Park Service’s Inventory and Monitoring Program, USGS’s Amphibian Research and Monitoring Initiative, and Idaho State University. In 2010, NRCC entered a cooperative agreement with National Park Service (NPS), and became a partner in the project. NRCC plays the key role of implementing field work according to the project protocols, accomplished by hiring a field coordinator and seasonal technicians with funds allocated by NPS and USGS.
Amphibians of the GYE are hardy animals, despite their naked skin and resemblance to species that proliferate in warmer climes. Four native species reside here, ranging from the valley floors to above 9,000 feet in elevation: the tiger salamander, boreal chorus frog, boreal toad, and Columbia spotted frog. All inhabit terrestrial areas as adults but depend on wetlands for breeding and egg deposition. We monitor potential breeding sites during the period when they may host wetland-dependent larvae (tadpoles), documenting the proportion of sites that are occupied by larvae of each species. This information is thought to provide the best handle for determining the occurrence and persistence of populations over time and across the region. Field crews annually conduct surveys for larvae in wetlands within a set of watershed units distributed across the two Parks. These watershed units were selected to provide inference about amphibian populations in the two Parks. Data obtained by the surveys are analyzed with statistical methods (Dr. William Gould, New Mexico State University) to provide occupancy rates and trends. In addition, we monitor amphibian sites at other locations to provide site-specific information for land managers, researchers, and land-owners.
Photo: Chorus Frog by Deb Patla