Amphibian diversity, distribution, and habitat use in the Yellowstone Lake basin

Abstract/Summary

Global amphibian population declines are being investigated through four interdependent fields of study: distribution and status, ecology, causes of declines, and environmental contexts. In Yellowstone National Park, work on amphibians has proceeded in all four of these fields. This paper describes amphibian species occurrence, distribution, and habitat-use patterns in the Yellowstone Lake area; summarizes the findings of a field study on habitat use by spotted frogs; and describes the directions and goals of continued amphibian investigations. Tiger salamanders, western toads, boreal chorus frogs, and Columbia spotted frogs all occur in the subwatersheds surrounding Yellowstone Lake. Chorus frogs and spotted frogs are the most common species. Salamanders are uncommon. Toads are rare, and we are concerned about their status in Yellowstone and in the Greater Yellowstone Ecosystem. A large variety of wetlands in the Yellowstone Lake basin provide breeding sites. Foraging and overwintering sites are also crucial to amphibian persistence. A case study of spotted frogs in the Lake Lodge area exemplifies this and underscores the need to understand habitat requirements, movement capabilities, and the effects of human activities. Amphibian investigations in Yellowstone over the next several years will probably focus on completing distribution surveys for inventory and monitoring purposes, research into habitat use and amphibian movements, and habitat mapping and modeling. The practical goal is an integrated information system that Yellowstone National Park can use for environmental analysis, project planning, monitoring, research, evaluation of ecosystem health, and education.