Mountain yellow-legged frog restoration amid a wildlife pandemic.

California’s mountain yellow-legged frogs are endangered. One reason is an ongoing wildlife pandemic (or, a panzootic). Worldwide, amphibians are threatened by a disease called chytridiomycosis, caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis. This disease has caused declines in frog and salamander species across six continents, including here in California. In a public seminar on Thursday 12 November 2020, our own Mountain Lakes Research Group Principal Investigator Tom Smith, PhD described some of the conservation tools that we study. Our goal is to help mountain yellow-legged frog populations persist in a landscape with widespread disease.

The recorded seminar is available to watch:

https://www.youtube.com/channel/UCRKf_rnxbSEvv_dp5lZtPBQ

This seminar was part of the UC Santa Barbara Natural Reserve System seminar series. Our research group is based out of the Sierra Nevada Aquatic Research Laboratory, which is part of the Natural Reserve System.

Frogs make an unexpected recovery

In this new video, UCSB videographer Spencer Bruttig talks to Roland during a visit to one of his Yosemite study sites and gets the latest on the outcome of frog conservation efforts there. Amazingly, despite all of the challenges the Sierra Nevada yellow-legged frog has faced during the past century, the frogs are making a remarkable comeback. Hear about this exciting turn of events from someone who witnessed the frogs’ decline and now the beginning of their recovery.

Frog rescue in Yosemite National Park

Adult Sierra Nevada yellow-legged frog (Rana sierrae)

In the Sierra Nevada, the winter of 2015-2016 was one of the driest on record. During the following summer, a habitat in Yosemite National Park containing Sierra Nevada yellow-legged frogs slowly dried up. Just before the last pools dried, Yosemite mounted a rescue of the tadpoles stranded in the shrinking pools. Several thousand tadpoles were collected and flown via helicopter to a lake upstream in the watershed. This video shows the rescue in action.

Frog conservation in Sequoia and Kings Canyon National Parks

Mountain yellow-legged frog populations in Sequoia and Kings Canyon National Parks are in steep decline due to the introduction of non-native trout and the ongoing spread of the amphibian chytrid fungus. As described in this new video, to prevent frog populations from being wiped out when the fungus arrives in a population, early life stage animals (e.g., tadpoles) are being collected from those sites, raised to adulthood in captivity, and reintroduced when they are less susceptible to fungal infection. This collaboration between the National Park Service, San Francisco and Oakland Zoos, and the Mountain Lakes Research Group may portend a brighter future for this imperiled amphibian.