Four Native Fish Species Return To Arizona Canyons

A multi-agency team converged in southeastern Arizona last week to carry out one of the largest reintroduction efforts in the state of threatened and endangered fish species. Four varieties of native fish were introduced to five new locations at the Muleshoe Ranch Cooperative Management Area (CMA), near Willcox.

The four native fish species - spikedace, loach minnow, Gila topminnow and desert pupfish - were transported by helicopter from their original sites in Aravaipa Canyon and Dudleyville to streams and springs in the Muleshoe CMA, which is managed jointly by The Nature Conservancy, USDA Forest Service and U.S. Bureau of Land Management.

Helicopters on loan from the Bureau of Reclamation were used to transport the fish from their original locations to the new sites. Eight-hundred spikedace and loach minnow were captured in Aravaipa Creek, then loaded into special transport drums and flown to their new home at Muleshoe. Field biologists transferred the fish into perennially flowing streams using a carefully regulated process that allows the fish to acclimate to the new waters. On the second day of the project, 2,000 desert pupfish and Gila topminnow were transported from a pond in Dudleyville managed by The Nature Conservancy to their new locations.

"Reintroduction efforts of endangered native fish populations have been undertaken in the past with varied success," said Ken Wiley, stewardship director of The Nature Conservancy in Arizona. "The chief reasons for failure include the presence of invasive species, the impact of human activities on the water quality and drought."

"Most native fish reintroductions typically focus on one, maybe two species. The reintroduction of four native fish species is monumental and is vital since all are imperiled to various degrees," said BLM biologist Heidi Blasius. "Numerous stockings for both Gila topminnow and desert pupfish have occurred over the years, whereas the last reintroduction efforts for loach minnow and spikedace occurred in 1968 and 1970. Neither earlier reintroduction for loach minnow or spikedace was successful, so much is depending on this effort."

The reintroduction is a collaborative project unprecedented in scale for Arizona. Additional partners include the U.S. Fish and Wildlife Service, Bureau of Reclamation, Arizona Game and Fish Department, Arizona Land Department and Arizona State University. The reintroduction effort entailed a three-year planning process that included assessment of appropriate species, suitability of relocation sites, coordination with local landowners and development of a follow-up monitoring plan.

"In Arizona, the state of streams and riparian areas is poor; there simply aren't many places anymore where these creatures can live," Wiley said. "Thanks to the management of the CMA partners, these streams in the Muleshoe CMA provide excellent, healthy habitat for the fish. The water quality is great and the presence of exotic competitors is minimal."

"Establishing populations of these fish in the Muleshoe CMA will enhance the survival and recovery of each of these species," said U.S. Fish and Wildlife Service biologist Mary Richardson.

Relocation sites were carefully chosen for each species based on water flows, temperature, substrate type and the presence of other aquatic species to offer optimal conditions for the fish to survive in their new habitat. The introduction of non-native predatory and competitive fishes has contributed to the overall decline of the species included in the reintroduction.