Biologists are puzzled by the mysterious deaths of 104 endangered mountain yellow-legged frogs in breeding tanks at a California zoo.
There are now only two frogs left at the Fresno Chaffee Zoo, one of three zoos participating in a wildlife breeding program to reintroduce frogs rescued after the 250-square-mile Angeles National Forest wildfire in Los Angeles two years ago.
Zoo director Scott Barton tells the Los Angeles Times that they haven't determined why the frogs died. He says the zoo may send the two remaining frogs elsewhere to see if someone else will have better luck.
Fewer than 200 mountain yellow-legged frogs are believed to exist and the Station fire destroyed critical habitat.
Zoos in Fresno, Los Angeles and San Diego are involved in the public-private effort to re-establish the yellow-legged frog population in Southern California.
