PHOENIX— The Center for Biological Diversity today filed a notice of its intent to sue the U.S. Fish and Wildlife Service and Arizona Game and Fish Department for failing to address decades of damage to the state’s endangered aquatic species from non-native fish stocking, in violation of the Endangered Species Act.

“Decades of stocking invasive fish in Arizona has driven most of our state’s native fish to the brink of extinction,” said Taylor McKinnon, Southwest director at the Center for Biological Diversity. “This legal action is about accounting for the damage that’s been done and securing the funding needed to give these rare desert fish a chance to recover.”

Today’s legal action seeks to ensure that federal funding for stocking non-native sportfish in Arizona supports recovery of the state’s endangered fish, snakes and frogs, and doesn’t contribute to their further decline.

Measures to help endangered fish include constructing barriers to prevent stocked fish from escaping from reservoirs into endangered species’ streams, monitoring and removing them from those streams and their watersheds, restoring endangered species habitat, and reintroducing endangered species to streams they previously lived in.

Since 1950 the Fish and Wildlife Service has provided Arizona with more than $414 million in federal sport fishing funds under the Dingell-Johnson Sport Fish Restoration Act. This has funded the introduction and spread of non-native fish throughout the state.

The Service did not provide a biological opinion for the statewide program under the Endangered Species until 2011. A decade later when it renewed the non-native fish stocking program, the Service removed many of the safeguards for endangered species that had been required under the 2011 review.

“The current program includes some conservation measures like stocking triploid rainbow trout, but these steps fall far short of what’s needed to help Arizona’s endangered species recover after decades of damage and neglect,” said McKinnon. “Saving these animals will require serious commitment to restoring and protecting their habitat and keeping invasive species out.”

Non-native fish are a leading cause of the decline of Arizona’s native aquatic species. About 85% of the state’s native fish species are in decline — a higher percentage than in any other state — and most are protected under the Endangered Species Act. They include Gila topminnows, Gila chubs, loach minnows, spikedace, Little Colorado spinedace, razorback suckers and bonytails. Other federally protected aquatic species harmed by non-native fish include narrow-headed gartersnakes, Northern Mexican gartersnakes and Chiricahua leopard frogs.

To avoid litigation, both agencies have 60 days to respond to today’s notice and address violations.