California's Aerial Fish Stocking Program Endangers Native Frogs

BERKELEY, CA -- Conservation groups led by Pacific Rivers Council want aerial fish stocking stopped in California's high mountain lakes. The non-native fish pose a direct threat to the increasingly rare amphibian species that are native to those lakes.

Scientists believe that decades of over-stocking of fish by DFG, and stocking in inappropriate places, has pushed several native frog species to the brink of extinction. In particular, the mountain yellow-legged frog (Rana muscosa) and the Cascade frog (Rana cascadae) both have been especially hard hit by these practices. Introduced fish compete with native frogs for scarce food resources and also directly prey on them in both the tadpole and adult stage.

Earlier this year, Robert C. Hight, Director of the California Department of Fish and Game (DFG), issued a temporary moratorium on fish stocking in high elevation lakes. The survey program was intended to help the agency make better fish stocking decisions by providing DFG with data on where the remaining frog populations were located and just how many frogs are still left in the wild. In early July, the Director reversed course and lifted the moratorium despite the fact that important field surveys for these sensitive species had yet to be completed.

"How can he make good management decisions without the necessary scientific data upon which to base them?" said Dr. Robert Stack, Director of the Jumping Frog Research Institute (JFRI) in Calaveras County. "Even a frog knows that its a wise thing to 'look before you leap.'"

"We're really only asking the Director to use some common sense here," said Deanna Spooner of the Pacific Rivers Council. "DFG is supposed to be the state agency that helps our threatened and sensitive native wildlife species, not the one that drives them towards extinction. The agency needs to make its stocking decisions based on reliable survey data and a thorough independent scientific review."

"We believe that resuming stocking without completing the surveys violates the California Environmental Quality Act, which requires state agencies to thoroughly analyze the impacts of a program on the environment. Up to now the statewide stocking program has been "exempt" from undergoing such an analysis," said Brent Plater, an attorney with the Center for Biological Diversity. "We urge Director Hight to follow the law, as his decision to resume aerial stocking clearly has the potential for significant impacts."

In a letter to Director Hight, the conservation groups also note that such stocking sometimes creates poor fisheries, wastes public resources, and could lead to the increased future use of rotenone to "undo" mistakes currently being made. "Once this or some future Director realizes that stocking mistakes have been made, there's a real possibility that DFG will come back and propose to use rotenone (a poison that not only kills the non-native fish but also kills the native fish and amphibians) in an attempt to undo the damage," said Robert Stack "Unfortunately, this "solution" has devastating repercussions, and quite frankly, DFG has a very poor track record in using this chemical poison."

The groups specifically called on Director Hight to reinstate the moratorium until the amphibian surveys and an Environmental Impact Report were completed, and to also undertake a full analysis of the impact of rotenone on aquatic ecosystems. Signatories to the letter included representatives from the following conservation organizations: Pacific Rivers Council, Center for Biological Diversity, California Wilderness Coalition, Living Rivers, Jumping Frog Research Institute, Plumas Forest Project, and the Central Sierra Environmental Resource Center.