Two weeks ago, 43 endangered Sierra Nevada yellow-legged frogs took to the skies in a helicopter from the Oakland Zoo. A team transported them to their new home in the high country of Sequoia and Kings Canyon National Parks. The zoo has now successfully translocated its 1,000th frog to its mountain home.  … The Sierra Nevada yellow-legged frogs (Rana sierrae), also called yellow-legged frogs, used to be common across California’s alpine lakes and streams. Keeping insect populations balanced and feeding predators like birds and snakes. Non-native trout introduced in the late 1800s were the first blow to this native species. The trout ate the tadpoles in large numbers.