HAGERMAN, Idaho (AP) -- Federal fish biologists say a decline in water flows from natural springs at a southern Idaho hatchery could one day mean fewer adult steelhead returning to spawn in Northwest rivers.
Officials at the Hagerman National Fish Hatchery, operated by the U.S. Fish and Wildlife Service, say reduced flows of cold, spring water used at the hatchery are forcing them to cut back by about 7 percent the number of steelhead smolts produced and introduced each year into the Snake River.
The cutback is a fraction of the more than 55,000 adult steelhead the Hagerman hatchery and other hatcheries run by Idaho, Oregon and Washington strive to provide each year.
But Hagerman Project Leader Brian Kenworthy says the hatchery's water supply, which has been on the decline for several years, could be an indicator of more significant troubles in the future.
The clear, cold spring water emitted from the rock walls along the Snake River is ideal for raising fish. The area where the springs are located, known as Thousand Springs, also supply water to private trout farms and other public fish farms that raise trout, sturgeon and other species.
The springs are fed by the massive Eastern Snake Plain Aquifer. In recent years, declining water flows at the springs have been a source of controversy between fish producers and southern Idaho farmers and ranchers who pump water from the aquifer to nourish crops.
State lawmakers this year approved an aquifer management plan, which includes plans to replenish, or recharge, and stabilize levels.
Kenworthy said the reductions in smolt production means fewer fish for sportsmen in Idaho, Oregon and Washington.
"We see it as providing a product for the citizens of the Northwest," Kenworthy told the Times News.
The Hagerman hatchery aims to raise enough smolts each year so an estimated 13,600 steelhead can return as adults to spawn. To meet that goal, Kenworthy said the hatchery must produce and release about 1.45 million smolts each year, a return rate of about 1 percent.
Kenworthy says he'll have to cut back by 100,000 smolts soon. The hatchery was revamped and expanded in 1963 as part of the Lower Snake River Compensation Plan to offset losses of salmon and steelhead caused by the series of dams located on the lower Snake River.
That reduction comes after the Hagerman facility recently boosted production to make up for a 160,000-smolt loss at the nearby state-run Magic Valley Fish Hatchery, said Scott Marshall, program manager for Fish and Wildlife Service.
Information from: The Times-News, http://www.magicvalley.com
Copyright 2009 The Associated Press.