JACKSON, Wyo. — While amphibians may go unnoticed by many in the Greater Yellowstone Ecosystem, their contribution on the landscape is considered critical.
Charles R. Peterson, professor emeritus in the Department of Biological Sciences at Idaho State University, has been part of an almost 20-year amphibian monitoring program in Yellowstone National Park (YNP) and Grand Teton National Park (GTNP). Peterson started following amphibians in YNP and GTNP in 1991 and continued the work for a little under a decade with help from the National Park Service (NPS) and a variety of other agencies.
Peterson credits the added assistance from the U.S. Geological Survey (USGS) to expand the program, and at the end of the 1990s there was increased collaboration from the NPS that allowed the current amphibian monitoring program for the two Parks to be developed.
Peterson confirms the program is one of the longest amphibian monitoring programs in the western U.S. His photo exhibit, in collaboration with Deb Patla, Andrew Ray and Ben LaFrance, titled “Amphibians and Wetlands of the Greater Yellowstone Ecosystem,” will be open to the public at the Teton County Library until July 10. For those unable to make it, a virtual version of the exhibit can be found here.
The program’s research underlines how amphibians are an important link in the food chain due to their intermediate size; amphibians feed on many smaller species and in turn also get eaten by larger animals.
Amphibians also act as important indicators of landscape health. Since they go through both terrestrial and aquatic life stages, amphibians get exposed to problems that occur both in the water and on land and can highlight conservation concerns. Peterson notes that their smooth, moist and permeable skin makes these species very susceptible to environmental conditions, allowing them to be early indicators of pollution.
Peterson says changes in habitat are a big worry for amphibians in the GYE, where climate change and global warming are causing wetlands to dry out and are exacerbating habitat fragmentation due to development.
“Even within the national parks, there is an impact of development,” Peterson tells Buckrail. “Things like roads, buildings and parking lots have affected [amphibian] populations.”
Peterson also says disease has turned out to have an unexpectedly large impact on amphibians. What’s known as “chytrid fungus,” a human-introduced disease into the ecosystem, is affecting western toad and spotted frog populations. Peterson says researchers believe it to be responsible for western toad and leopard frog decline. While he notes the GYE hasn’t seen declines as extreme as they are in other places (chytrid fungus has wiped out scores of species in the tropics), he still emphasizes the risk of its presence.
“It’s probably the worst wildlife disease ever,” Peterson says. “It strikes me that that’s the most likely reason that leopard frogs have disappeared from GTNP.”
Viral disease, like Ranavirus, has affected some of the frogs and the salamanders in the GYE as well.
To help support local amphibian populations in the face of these challenges, Peterson stresses the importance of keeping a connection between culverts and road design and using beaver restoration as a tool to enhance wetlands. Radio telemetry studies in the GYE have confirmed that frogs and toads move around quite a bit, as far as several kilometers, so reroutes somewhere like the Grand Loop highway in YNP through their habitat results in heavy road mortality for amphibians.
“You can make animal crossings more amphibian friendly,” Peterson says. “Another really important thing is beaver restoration. Beavers are really important to amphibians.”
Peterson says a study in the Northern Rockies confirms that one of the most important parts of amphibian habitat is the presence of beavers.
Peterson will also give a presentation about the exhibit at 6 p.m. on July 9 at the Teton County Library, hosted by the Jackson Hole Bird and Nature Club. The event is free and open to all.
