Pacific Southwest Region
California, Nevada and Klamath Basin

Rare Tadpoles Released for First Time into Wild Stream

Aug 25, 2010

FOR IMMEDIATE RELEASE
August 24, 2010

U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192

Contact Information: 

Ben Young Landis, USGS
Phone: 916-616-9468

Dani Dodge Medlin, San Diego Zoo
Phone: 619-685 3291

Becca Fenwick, James Reserve
Phone: 951-827-6835

Additional contact:  Jane Hendron, USFWS, 760-271-6487 or Jane_Hendron@fws.gov

Editors’ Note: Adam Backlin, head of this USGS frog reintroduction and monitoring project, is available for phone interviews on Tuesday afternoon and Friday. Please contact Ben Landis for details. The San Diego Zoo will provide photos later today, and video on Aug. 25, 2010. 

 Rare Tadpoles Released for First Time into Wild Stream
Release follows prior introduction of mountain yellow-legged frog eggs in the same area

IDYLLWILD, CALIF. — Thirty-six rare tadpoles were released into a wild steam today near Idyllwild, Calif. as part of a program aimed at giving the nearly-extinct, Southern California population of mountain yellow-legged frogs a chance of thriving in the wild again.

The tadpoles were bred at the San Diego Zoo Institute for Conservation Research and carefully transported to the University of California James San Jacinto Mountains Reserve, part of the University of California Natural Reserve System. There, the tadpoles were released into a quiet stream where researchers can monitor them regularly. This release of tadpoles follows a release of mountain yellow-legged frog eggs in the same area four months ago.

The release was lead by U.S. Geological Survey in collaboration with the U.S. Forest Service, U.S. Fish and Wildlife Service, and the San Diego Zoo. Other partners who have worked to help save the species include the California Department of Fish and Game, the California Department of Transportation (Caltrans) and the San Diego Museum of Natural History.

“This is the first time we have reintroduced captive-bred offspring of this species into the wild,” said Adam Backlin, a scientist with the USGS Western Ecological Research Center. “This tadpole release will refine our methodology for future releases and help us find the most effective and successful strategy.”

Globally, amphibians are on the decline because of habitat loss, effects of climate change, pesticide drift, introduction of nonnative species in the past, and the spread of a deadly pathogen called the chytrid fungus. The mountain yellow-legged frog is one of three frogs or toads on the federal Endangered Species List in Southern California, and has recently been proposed for listing under the California Endangered Species Act. Today, only a small wild population of less than 200 adult mountain yellow-legged frogs can be found in the San Gabriel, San Bernardino, and San Jacinto mountains.

In April, the same team of researchers who released the tadpoles into the creek released about 500 mountain yellow-legged frog eggs. The eggs also were the result of breeding at the San Diego Zoo Institute for Conservation Research. Scientists believe about 40 of those morphed into 5-millimeter (less than ¼ inch) -long tadpoles.  The tadpoles from that first release are so small, it has been difficult for scientists to determine how many survived. The tadpoles released today were about 40 to 50 millimeters (1½ to 2 inches) long, which gives them a better chance of survival, said Jeff Lemm, an animal research coordinator for the San Diego Zoo.

The San Diego Zoo Institute for Conservation Research was the first to breed the Southern California mountain yellow-legged frog outside of its native habitat. Historically, scientists have had great difficulty breeding frogs in captivity. This year, the Zoo scientists discovered that the frogs’ breeding behaviors increased after frogs in the lab were chilled to temperatures that resembled their high mountain stream environment.  Scientists hope the second year of breeding will result in a higher fertility rate.

“Reproduction in the lab, and release is a small first step, but it is a great one,” said Lemm. “We hope to have many more tadpoles to release in years to come and look forward to helping in the recovery of this frog.”

“This is a very exciting day for everyone involved in this important effort to save the mountain yellow-legged frog,” said Becca Fenwick, director of the James San Jacinto Mountains Reserve. “We are proud to be part of the effort to save this species that once thrived throughout Southern California. We will be monitoring carefully in hopes these tadpoles will be the beginning of the species’ resurgence.”

The San Diego Zoo’s breeding program, in conjunction with its partners, began after a wildlife biologist with the San Bernardino National Forest noticed declining creek water levels in Dark Canyon in 2006. The Fish and Wildlife Service salvage effort started the next day. Recovered tadpoles were taken to the San Diego Zoo Institute for Conservation Research, where they metamorphosed into frogs. More recently, some frogs were salvaged due to pollution from the L.A. Station Fire. Those frogs are now at the Fresno Chaffee Zoo's breeding program.

The James San Jacinto Mountains Reserve is one of thirty-seven University of California reserves throughout the state protecting over 280,000 acres, and making them available for research, university level instruction and public outreach.

U.S. Fish and Wildlife Service is working with others to conserve, protect and enhance fish, wildlife, plants and their habitats for the continuing benefit of the American people.

The San Diego Zoo’s Institute for Conservation Research is dedicated to generating, sharing and applying scientific knowledge vital to the conservation of animals, plants and habitats worldwide.

-- FWS --

In partnership with: San Diego Zoo, U.S. Fish and Wildlife Service, U.S. Forest Service,
California Fish and Game, and James San Jacinto Mountains Reserve