Effective removal of the American bullfrog (Lithobates catesbeianus) on a landscape level: long term monitoring and removal efforts in Yosemite Valley, Yosemite National Park

A successful landscape-level eradication of the invasive American bullfrog (Lithobates catesbeianus) from Yosemite Valley, Yosemite National Park, has been achieved through long-term removal efforts by the National Park Service (NPS). Starting in 2005, targeted removal using hand, net, and spear techniques led to an 86% reduction in bullfrog populations within the first year. By 2012, no signs of breeding were observed, and the last individual was recorded in 2019. The NPS utilized environmental DNA (eDNA) surveys and audio recordings from 2015 onward to enhance detection accuracy. Following eradication, restoration efforts introduced the federally threatened California red-legged frog (Rana draytonii), marking the first documented successful bullfrog removal on a landscape scale. This study demonstrates that invasive species can be effectively managed in protected areas, facilitating the recovery of endangered native species.

Kamoroff, C., Daniele, N., Grasso, R. L., Rising, R., Espinoza, T., & Goldberg, C. S. (2019). Effective removal of the American bullfrog (Lithobates catesbeianus) on a landscape level: long term monitoring and removal efforts in Yosemite Valley, Yosemite National Park. Biological Invasions, 22(2), 617–626. https://doi.org/10.1007/s10530-019-02116-4