THOUSAND OAKS (AP) — A discovery involving a rare California frog has researchers hopping for joy.

The National Park Service says egg masses from the California red-legged frog were found last week in a stream in the Santa Monica Mountains near Los Angeles.

It’s evidence that the threatened species is reproducing.

The frogs haven’t been seen in the mountains since the 1970s. The Park Service has been trying to rebuild the population by transplanting them from nearby Simi Hills.

The March 14 discovery of nine egg masses indicates that after four years of effort, the population is sustaining itself.

Red-legged frogs famously appear in the Mark Twain story, “The Celebrated Jumping Frog of Calaveras County.”

The species once lived throughout California’s coastal areas but habitat loss and invasive species have shrunk the population.

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