Project overview: Uncover the impact of climate-driven wildfires and tree mortality on the endangered Pacific fisher by supporting park staff in monitoring populations with remote cameras, GPS collars, and scientific models.   

How your support helps: Yosemite National Park is home to the elusive, federally endangered Pacific fisher. This small, forest-dwelling mammal faces major threats from climate-induced habitat loss, largely driven by wildfires. 

In 2021, Yosemite Conservancy helped launch an ambitious fisher study to address the threat of extinction from drought-induced tree mortality and frequent wildfires. Using GPS collar technology and biological samples, researchers have been able to: uncover fisher movement patterns post-fire, locate and protect reproductive structures used by female fishers, model the effects of land management on fisher density, understand human impacts on fishers, and monitor current populations. 

These efforts will continue to contribute invaluable data necessary to recover the Pacific fisher in Yosemite and surrounding public lands. This project builds on multiple years of research conducted by numerous agencies and will allow land managers to make well-informed management decisions. 

This year: With your support, park biologists will continue to survey and monitor Pacific fishers using remote cameras and GPS satellite technology. This year, scientists will build on the wealth of information about preferred fisher habitat and contribute valuable data toward innovative fire-management strategies. This will protect both fishers and local landscapes for generations to come. 

Project partners: Yosemite National Park; University of California, Davis; Integral Ecology Research Center; Rocky Mountain Research Station 

Sarah Stock

Wildlife Biologist, Yosemite National Park

Project Notes

"This study is urgently needed to fill critical knowledge gaps on fisher habitat use and connectivity in a landscape drastically altered by tree mortality and wildfire."