Community News · Mariposa County
UCLA Study Finds Winter Fungal Infections Threaten Yosemite Toad Reintroduction
Researchers from UCLA and Yosemite collected approximately 1,800 skin samples across six sites from 2021 through 2023, discovering that young Yosemite toads carry heavy Batrachochytrium dendrobatidis (Bd) fungal infections after emerging from underground winter dormancy. The findings, announced by UCLA on October 1, have already changed Yosemite's reintroduction strategy: managers now allow captive-reared toads several years to grow before release, reducing overwinter infection risk. Federally designated critical habitat for the species includes portions of Madera and Mariposa counties, along with five other Sierra counties. The Yosemite toad received federal threatened status in 2014 and occupies roughly half its historically occupied sites.