Employees have begun setting gillnets at Ralston, Cagwin and Tamarack lakes in the Desolation Wilderness in an effort to remove trout and restore once-friendly frog habitat, the agency’s Lake Tahoe Basin Management Unit announced.
Over the next decade, the Forest Service plans to remove brook and rainbow trout from Margery, Lucille, LeConte and Jabu lakes in the wilderness area just west of Tahoe, they said.
The lakes were selected due to their proximity to current populations of the frog, a candidate for listing under the Endangered Species Act.
Prior to the 1950s, lakes in the wilderness area had no fish and supported viable frog populations, biologists said. Predation by introduced nonnative fish helped eliminate the frogs from more than 90 percent of their native habitat.
Biologists say it takes up to four years for the mountain frog to complete its life stages from egg to tadpole to adulthood, which leaves it vulnerable to predators like trout.
Research has shown that frog populations recover after fish removal, officials said, and other lakes in the wilderness area will be stocked for recreational fishing.