Sequoia and Kings Canyon National Parks in California’s Sierra Nevada mountains are now home to more than three dozen yellow-legged frogs recently released by staff from the Oakland Zoo. During the first week of August, the zoo said 43 mountain yellow-legged frogs were flown by helicopter to their release site near Laurel Lake.  The event marked the 1,000th yellow-legged amphibian released by the zoo during conservation efforts designed to save the species from disappearing entirely. Biologists said the frogs are part of a broader recovery program designed to pull the species back from the brink of extinction. Scientists attribute much of the population collapse to chytridiomycosis, a deadly fungal disease that has impacted animal populations worldwide.