Yellow Legged Frog Inventory at Sequoia, Kings Canyon, and Yosemite National Parks 2022-2023 - Open Format Dataset
National Park Service Inventory and Monitoring Division. 2026. Yellow Legged Frog Inventory at Sequoia, Kings Canyon, and Yosemite National Parks 2022-2023 - Open Format Dataset. National Park Service. Fort Collins CO https://doi.org/10.57830/2318110
The endangered mountain yellow-legged frogs (a species complex of Rana muscosa and R. sierrae) were once ubiquitous and abundant in lakes, ponds, and meadows of the high-elevation Sierra Nevada, in both Sequoia and Kings Canyon National Parks and Yosemite National Park. Both species declined or were extirpated in over 90% of their historic habitats due to the introduction of non-native predatory fish (trout) to high mountain lakes and the emergence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis). Habitat restoration (fish eradication) by both parks has allowed frogs to recover in many sites. Over several decades, frogs in some parts of the Sierra Nevada have evolved resistance or tolerance to Batrachochytrium dendrobatidis. However, other frog populations remain naïve to the disease, putting them at risk of extirpation when the disease inevitably invades. In 2022–2023, we inventoried approximately six hundred sites in both parks to 1) conduct surveillance for new disease outbreaks, 2) quantify frog recovery since previous surveys, 3) identify large frog populations capable of supporting future recovery actions, 4) identify sites/habitats capable of supporting future recovery actions. The results of the inventory surveys in Yosemite National Park indicate that Rana sierrae remains widespread, represented in virtually every basin or watershed visited. Generally, frog occupancy continues an upward trend, driven primarily by a small number of habitat restoration and frog population recovery actions like translocations and reintroductions. Survey results in Sequoia and Kings Canyon National Parks indicate that both Rana sierrae and Rana muscosa have limited occupancy but are present across the landscape and even thriving in a small number of sites. Increases in occupancy and abundance have occurred where habitat restoration and reintroductions have occurred, although the latter have been more limited in spatial scale than in Yosemite.
- Type
- Data Package
- Authors
- National Park Service Inventory and Monitoring Division
- Date of Issue
- 2026-09-08
- Publisher
- National Park Service
- DOI
- 10.57830/2318110
- Units
- SEKI , YOSE
- Keywords
- Batrachochytrium dendrobatidis, IMD, National Park Service, NPS, NPS Inventory and Assessment Program, NPS Inventory and Monitoring Division, NPS Species Inventory Program, occupancy, Open-format, Rana muscosa, Rana sierrae, visual encounter survery
- License
- Unlicensed (not for public dissemination)