Rare yellow-legged frogs are returned to drought-hammered San Gabriel Mountains
TRAFFIC: The first to arrive to the San Gabriel River, but none of the first have made it to the San Gabriel River.
SAN GABRIEL, Calif.—The first to arrive to the San Gabriel River, but none of the first have made it to the San Gabriel River. At first, only two or three dozen frogs make it out of a year when water is so low and water temperatures so high that they will not survive the journey.
These first-to-arrive frogs are yellow-legged frogs. They first appeared in 1997 and never again appeared in the San Gabriel Mountains until last year.
“It’s really hard to tell what’s going on because they are so shy,” says Matt Smith, the head of the U.S. Fish and Wildlife Service’s Wildlife Health Program, in an interview from his office in the San Gabriel Mountains, which is south of Pasadena in Los Angeles County. “They are extremely vulnerable.”
On a day in January, when temperatures hit the mid-80s, with no rain, the high-country peaks of the San Gabriel Mountains were so dry that a single yellow-legged frog could survive in the dry stream bed by using its camouflage to blend in with rock. But after a couple of drier weeks, when the mountains were once again well watered, the yellow-legged frogs disappeared.
“It’s the little things,” said Smith. The frogs were spotted on January 17 in the streams, but after two days, people stopped seeing them because they were either hiding in the rocks or in the creeks or wetlands around them. “A few people that worked here said they had seen them and they were so far from dry, they were not leaving.”
It is a mystery with no clear answers. Most people just assume the yellow-legged frogs are going extinct because of the drought-induced water shortage in the San Gabriel Mountains. But some believe the yellow-legged frog population is thriving because most of the breeding females who left in 1998 were carried out of the San Gabriel Mountains by a strong El Niño in 1997. But many of those who were carried out did survive.
At one point, yellow-legged frogs were thriving, but the water in the San Gabriel River was so low and the water temperature so high that the