November 2007 |
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Endangered Native Fish Get Helicopter Rides To New HomesA multi-agency team converged in southeastern Arizona last week to carry out one of the largest re-introduction 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." BLM biologist Heidi Blasius said, "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. “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 re-introduction 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." U.S. Fish and Wildlife Service biologist Mary Richardson said, "Establishing populations of these fish in the Muleshoe CMA will enhance the survival and recovery of each of these species." 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. "After years of planning and coordination to carry this reintroduction off, there's a tremendous feeling of accomplishment and optimism for the success of our efforts," said Tony Robinson, CAP projects program manager for the Arizona Game and Fish Department. "It's no exaggeration to say that we're really looking at one of the last chances for these fish to exist." All four species are imperiled throughout their native Gila River basin and are federally listed under the Endangered Species Act.
Data collection will take place over the next five years to monitor the success of the re-introduction. Program modifications and additional stockings will be used to augment native fish populations and improve the likelihood of establishing self-sustaining populations of each of the four species. The Muleshoe Ranch CMA is a 55,000-acre mosaic of public and private land. Within its boundaries is most of the watershed area for seven permanently flowing streams, representing some of the best remaining aquatic habitat in Arizona. Some 80 percent of the region's wildlife species depend upon these streamside communities at some time in their lives |
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