November 5, 2006
Beleaguered native fish receive biological boost
From a recent AZ Game and Fish Department (AZGFD) Press Release:
One of Arizona's beleaguered native fish just received a biological boost. AZGFD biologists were able to stock 150 longfin dace into Upper Mineral Creek, which is located near the ASARCO Mine between Superior and Kearny.
"This is an important conservation action for native fish in Arizona," says Cori Carveth, a native fish biologist with the department. "Upper Mineral Creek was once home to both longfin dace and the endangered Gila chub, but was devoid of any fish from 2001 until August, when an initial group of dace were stocked."
The great news is that the fish stocked in late August have apparently taken to their new home. "The creek is currently full of thousands of young-of-the-year longfin dace. We also saw a few of the adults that we stocked in August. Depending on the continued success of the longfin dace, we hope to reintroduce endangered Gila chub there in the future," Carveth says.
Longfin dace are small native fish ranging up to 2.5 inches in length that have a remarkable capability to disperse into new habitats, appearing a few hours or days after flows reestablish in small desert streams, such as during summer rains.
"These fish are superbly adapted to the challenging environment of desert streams and creeks. Longfin dace can survive in tiny volumes of water beneath logs, rocks or even mats of algae, then reproduce a few days after summer rains rejuvenate a stream," says Carveth.
Longfin dace are wide-ranging and survive in hot, low-desert streams at around 1,360 feet in elevation, but also inhabit clear, cool brooks at higher elevations up to 6,740 feet. They are primarily found in the Gila and Bill Williams river drainages.
Biologists point out that of Arizona's 35 native fish, one is extinct, and almost 75 percent are either federally listed under the Endangered Species Act, are candidates for listing or are listed as a wildlife species of special concern.
Jim Warnecke, a fisheries biologist in the Mesa region, says the future of sport-fish management is inseparably intertwined with that of native fish management. "Factors leading to declines of native fish include stream degradation and the introduction and spread of non-native fish and amphibians, such as the bullfrog."