Yosemite Valley Predators: Raccoons, Ravens and River Otters – 2017

Yosemite scientists survey Valley predators to protect endangered species. Photo: Rick Kimble.

Thanks to Conservancy donors, aquatic ecologists are restoring two rare species in Yosemite Valley: the western pond turtle and the California red-legged frog. As scientists release frogs and turtles along the Merced River, they are bringing back animals whose populations in the park have declined precipitously or vanished altogether.

Now, scientists aim to fine-tune the reintroduction process by studying species that prey on amphibians and reptiles. Mapping the distribution and abundance of three key hunters — river otters, ravens and raccoons — will help the aquatics team release frogs and turtles in predator-free areas. Findings will inform efforts to improve food storage and waste disposal in areas frequented by ravens and raccoons, two non-native species that have moved into the Valley to forage on human food and trash.

Your support helps scientists study three Yosemite Valley species in order to give rare frogs and turtles the best chance at survival.

Partnering with Yosemite National Park and University of California, Davis.

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Project Notes
Yosemite scientists survey Valley predators, like this raccoon, to help ensure the success of endangered species recovery. Photo by David Grimes

The NPS has a mandate to preserve and protect its wildlife, and biologists in Yosemite are working hard to not only protect current species, but also to restore lost ones. Mapping predators helps us protect endangered species.

Rachel Mazur
Wildlife Biologist
Yosemite National Park