Recovery of Endangered Sierra Nevada Yellow-legged Frogs (Rana sierrae) in Harvey Monroe Hall

Recovery of Endangered Sierra Nevada Yellow-legged Frogs (Rana sierrae) in Harvey Monroe Hall

This project will reintroduce up to 50 frogs from the Conness Ponds in Yosemite National Park to Maul Lake annually for at least three years. The actual number will be based on survey results prior to collection (15-20 minimum; 50 maximum). Maul Lake (receiving location) is fishless and ready for frog reintroductions. CDFW will coordinate with YNP Ecologist Rob Grasso and UCSB Researcher Roland Knapp. Adult frogs are the best life stage to move, and CDFW will move only adult frogs. CDFW will translocate no more than 10% of each life stage from a donor population per year. The Conness Ponds source population has been monitored every year since 2007 (SNARL). Using this dataset, the project team believes there should be no impact to the donor population. Maul Lake is at an elevation of 3115m, has a maximum depth of 8.5m, a perimeter of 562m and a surface area of 1.8 hectares. Frogs will be introduced to the lake in 2021, 2022 and 2023. Maul Lake (and other sites within the Saddlebag Lake Planning Watershed) have historic records of Sierra Nevada Yellow-legged Frogs presence in the past. Nonnative fish introductions and disease are believed to have extirpated the populations prior to targeted surveys. Fish were removed from Maul Lake in 1998 (SNARL) and 2021 net sets confirm that the lake has remained fishless. There should be no impact to the destination area. It should recover to a higher standard than is currently available. The translocation and fish removal are part of the INYO NF Management Plan (Wolfenden, 1992) for the Harvey Monroe Hall Research Natural Area. No ground disturbance will take place.

Mono

Unincorporated

Mono