It was one small leap for a frog, but a giant step for the California red-legged frog kind.
The California Department of Fish and Wildlife, along with partners, released the 10,000th frog following a decade-long conservation effort in Yosemite National Park on Thursday, May 7, the agency announced.
The frogs, which can grow up to five inches long, are federally listed as a threatened species and vanished from Yosemite for decades after being overrun by invasive species.
But thanks to recent efforts led by the National Park Service — alongside the U.S. Fish and Wildlife Service, the CDFW, Yosemite Conservancy and San Francisco Zoo & Gardens — the amphibians are on the rise.
Now, the species has established a foothold and is successfully breeding, Yosemite National Park Aquatic Ecologist Rob Grasso explained.
“This milestone reflects years of focused work to restore a species that plays an important role in the park’s ecosystem,” he said. “After invasive bullfrogs eliminated red-legged frogs from the area decades ago, we removed those threats and created conditions for recovery. Today, multiple generations of frogs are established in Yosemite Valley.”
Why California red legged frogs disappeared from Yosemite
Rather than human encroachment or climate change, the main challenge for California red-legged frogs has come from invading fellow amphibians.
American bullfrogs introduced into the local ecosystem are primarily to blame for the plight of the California red-legged frog, CDFW officials said.
Also, raccoons.
“Elevated raccoon populations, fueled by open refuse sites that remained in use until the 1970s, also contributed to the loss,” according to a CDFW statement. “Park staff spent decades removing bullfrogs, while habitat improvements tied to the Merced River Plan restored wetlands, streambanks, and river systems critical to the frog’s survival.”
Why the California red legged frog matters to the state
The California red-legged frog was designated the official amphibian of the Golden State in 2014.
“The California Department of Fish and Wildlife is proud to have assisted the recovery of California’s official state amphibian in Yosemite,” CDFW Amphibian and Reptile Conservation Coordinator Laura Patterson said.
The credited California voters for approving grants that have made the project possible.
Officials also thanked landowner Diane Buchholz of Garden Valley, who they said allowed researchers to collect frog eggs from her property.
From eggs to wild frogs inside a San Francisco breeding program
The effort to restore the threatened species largely depends on a San Francisco-based facility created through a partnership between the National Park Service and the San Francisco Zoological Society, CDFW officials said.
“At the facility, staff raise frogs from wild-collected eggs to 1- and 2-year-old juveniles in a controlled environment before releasing them into the park,” the statement said.
According to San Francisco Zoo & Gardens Director of Field Conservation, at the outset of the program in 2016, “no California red-legged frogs remained in Yosemite Valley.”
“Today, every frog in the valley traces back to this effort,” she said. “Despite drought, severe winters and flooding, the population has proven resilient.”
Under the program, staff plan to release roughly 830 young frogs this year and raise about 600 eggs, officials said.
The Mark Twain connection to California red legged frogs
The 10,000 frogs released on Thursday were named “Twain.”
The species gained notoriety after being mentioned in Mark Twain’s story, “The Celebrated Jumping Frog of Calaveras County,” which starred a California red-legged frog.
“The species, the largest native frog in the western United States, grows 2 to 5 inches long and is known for its reddish underside and soft, short calls,” the CDFW stated. “It inhabits ponds, streams, and wet meadows.”
This article originally appeared on Victorville Daily Press: Threatened California red-legged frog marks comeback in Yosemite
Reporting by Brian Day, USA TODAY NETWORK / Victorville Daily Press
USA TODAY Network via Reuters Connect
