Tuesday, December 28, 2010

Broodstock Hatchery Threatens Wild Sandy River Steelhead

Over the last decade, many populations of wild steelhead in the Columbia River have seen modest recoveries from low levels observed during the 1990s. Biologists have largely attributed increased wild abundance to improved ocean conditions at the mouth of the river. Meanwhile the Sandy River, home to one of the largest and historically important steelhead runs in the Lower Columbia has continued to decline. All this despite increased habitat protection and the removal of two dams in the basin. Meanwhile ODFW continued to plant nearly a quarter of a million hatchery steelhead into the river annually. During that time NMFS estimated a stray rate of nearly 45% for hatchery fish spawning in the basin.

In 2000, on top of the two hatchery programs already in place ODFW initiated a wild broodstock hatchery program which now harvests nearly 15% of the wild run. Meanwhile the wild population which as recently as 1980 topped 4000 fish now hovers below 5% of historic abundance at 700-1000 fish annually. Mining 15% of an ESA listed wild run to enhance harvest opportunity is absolutely unacceptable, furthermore wild broodstock hatchery fish residualize at a much higher rate and spawn at the same time as their wild counterparts dramatically increasing the ecological impacts of the program and the likelihood that hatchery fish spawn with wild. On the nearby Hood River, Hitoshi Araki and Michael Blouin of ODFW showed that even one generation in captivity is enough to significantly reduce the reproductive success of hatchery spawners so on the whole broodstock programs offer no conservation benefit to wild fish and may actually pose greater risk than traditional early timed stocks.

All this in a river with generally good habitat on the Columbia where some other populations have recently been trending upwards. The glaring different between the Sandy and other river systems where wild fish have recently been increasing in numbers...those systems have seen hatchery interactions with wild fish reduced or eliminated entirely. The Molalla River on the the Lower Willamette River has seen a more than 12 fold increase in wild steelhead abundance since hatchery programs were discontinued and populations continue to increase. Wild summer runs on both the Wind and Washougal Rivers have also benefited greatly from WDFW efforts to keep hatchery fish off the spawning grounds. Given the geographic proximity of these rivers outmigrant steelhead from the Molalla, Wind and Washougal have in all likelihood been experiencing the same marine environment as fish from the Sandy River. With high quality habitat throughout the Sandy basin, there is no reason the wild run could not recover to an even greater abundance than pre 1980s levels, however until ODFW deals with the impact of its hatchery programs on wild fish that will not happen. Instead, populations of wild steelhead on the Sandy will continue to decline as managers mine harvest 15% of the wild run to supplement harvest.

Sandy River Steelhead Returns at Marmot Dam

More information from NFS River Steward Spence miles at the Whitefish Can't Jump Blog:


Write ODFW and tell them what you think of their management of the Sandy.

Todd Alsbury
North Willamette District Biologist
Oregon Department of Fish and Wildlife

Ed Bowles
Fish Division Director
Oregon Department of Fish and Wildlife

Roy Elicker
Oregon Department of Fish and Wildlife

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