The Mountain Yellow-legged Frog, MYLF, Rana Muscosa, once a common frog in the Southern
California mountains, was placed on the Endangered Species list in 2002. At that time, less than 200 of
these frogs were reported to live in the San Gabriel, San Bernardino and San Jacinto mountain
streams. The last couple of years have brought extreme challenges to the recovery efforts being made
to prevent the extirpation of the frog from the San Jacinto mountains.
Decline of the MYLF over the years has been attributed to many factors including habitat loss,
nonnative predators (bullfrogs,trout) and a fungal disease, called chytridriomycosis. The Mountain
Fire of 2013 burned a portion of the habitat in the San Jacinto Wilderness, followed by a torrential
rainfall that caused ash and sediment to fill in some crucial creeks. The ongoing drought has added to
the current perilous state.
A critical component of the restoration efforts began in 2006 when numerous tadpoles were
rescued from several pools that were drying up in the San Jacinto mountains. Seventy-eight of these
tadpoles were transferred to the San Diego Zoo Institute for Conservation Research. This was the
beginning of the captive breeding program with the cooperation from various agencies including; US
Geological Survey, US Fish and Wildlife, US Forest Service, California Dept of Fish and Wildlife and
California Department of Transportation.
The first of many releases in the San Jacinto Mountains occurred at the James Reserve near Lake
Fulmor in 2011. The researchers discovered that releasing adult frogs is more successful long term
than tadpoles which had a lower survival rate. As a USFS volunteer, I participated in a release project
in the Fall of 2013. Good looking, healthy frogs were on their way to a new life in a couple of clear
mountain pools with perfect surrounding habitat. It is uncertain how many of them survived the
subsequent flash floods and last year's drought.