Influence of fish and habitat on amphibian communities in high elevation lakes in northeastern Oregon

Declines in lentic breeding amphibians in the western United States, particularly in relatively pristine areas, emphasize the need for information on the distribution, abundance, and ecology of these species. In 2000 and 2001, we surveyed 43 high elevation lakes in northeastern Oregon to determine the influence of introduced trout and of habitat characteristics on the reproduction of native amphibians occurring there. Long-toed salamanders and Pacific treefrogs were negatively affected by introduced trout. Habitat characteristics exerted more influence on the abundance of eggs and larvae of western toads and Columbia spotted frogs than the presence of trout. Our results indicate that the presence of fish may be detrimental to amphibian biodiversity in high elevation lakes.