Conservation team members prepare to release a red-legged frog at Yosemite National Park. (Photo courtesy of San Francisco Zoo/Twitter)

The San Francisco Zoo & Gardens reached a milestone recently when it released the 1,000th individual red-legged frog reared at the zoo into Yosemite National Park.

A pair of red-legged frogs swim into their new habitat in Yosemite National Park.

The species had been absent from Yosemite for 50 years before the zoo’s conservation team started a collaborative project three years ago with the National Park Service, Yosemite Conservancy, U.S. Fish & Wildlife Service and California Department of Fish & Wildlife.

The near-extinction of the species was mainly due to the introduction of the non-native bullfrog, according to the zoo.

A video of the frog release was posted on Twitter.