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About Applegater. (Jacksonville, OR) 2008-current | View Entire Issue (May 1, 2008)
Applegater May-June 2008 23 Williams Creek Watershed Council hosts fish trap on Williams Creek BY ARTHUR SHERMAN In spring of 2007, the Williams Creek Watershed Council (WCWC) along with the Oregon Department of Fish and Wildlife (ODFW), the Middle Rogue Steelheaders, Bureau of Land Management’s Grants Pass Resource Area and many local volunteers, operated a fish trap on lower Williams Creek. The trap was part of a statewide effort by ODFW to monitor juvenile salmonid production as part of the Oregon Plan for Salmon and Watersheds. One objective was to estimate the number of Chinook salmon fry as well as Coho salmon and steelhead smolts migrating out of Williams Creek. This project also helped determine the abundance of pre-smolt steelhead, Coho salmon, and resident cutthroat trout. Fish eggs, or roe, hatch into alevin or sac fry. The fry quickly develop into parr. Parr stay for one to three years in their natal stream before becoming smolts. As smolts, their body chemistry changes to allow the fish to live in salt water. The trap looks like a large mesh cone lying on its side on a floating platform. Fish swimming downstream pass into the trap and then into a holding tank. Each day the trapped fish were removed carefully, identified and counted. All the fish were then put back into the creek. Fish were trapped and counted in Williams Creek between March 5 and May 31, 2007. The resulting data provides important baseline information for measuring trends in fish populations. It also is used to identify factors that limit the health of the fishery. All of this is used to develop management strategies designed to protect and improve fish populations. Four different species comprised the majority of salmonid fish caught in the trap: Chinook salmon, Coho salmon, steelhead trout, and cutthroat trout. The fish counts were used to estimate the total numbers of fish of each species passing the site. After the fish are identified and measured, their fins are marked to avoid double-counting Chinook salmon juveniles were the most abundant species caught in the trap. Approximately 120,000 young Chinook migrated toward the Pacific Ocean during the trapping period. These fish came from eggs in the fall of 2006 and emerged from their shallow nests in stream gravels (called redds) in late winter/spring 2007. After two to six years in the Pacific they will return to Williams as adults. Approximately 3,900 Coho smolts, a federally protected species, outmigrated during the period. These fish were spawned in fall/winter 2005-2006 and emerged from their redds in spring 2006. They will migrate to the Pacific for one to two years, and then return as adults. Approximately 3,300 steelhead smolts outmigrated. These are on their way to the Pacific to grow to adulthood after residing in Williams Creek for one or two years. Additionally, there were approximately 3,500 pre-smolt steelhead (fish about a year old or less). These fish may reside in the mainstem Applegate (or possibly the Rogue River) for the summer months and return to Williams Creek or other Applegate tributaries to over-winter another year before heading to the ocean. Steelhead life histories are generally more variable than those of other species. Approximately 1,900 cutthroat trout of varying ages outmigrated from Williams Creek. These fish simply may migrate to and from the Applegate and Rogue Rivers and then back to Williams Creek and its tributaries. The larger rivers provide more food while the smaller streams provide refuge and spawning habitat. As far as it is known, Applegate River cutthroat do not migrate to the ocean. Additional native species caught in the trap were Pacific lampreys, small-scale suckers and sculpins. Non-native species caught include numerous redside shiners, bluegill, and one Umpqua pike minnow. The Williams Creek Watershed Council and ODFW are operating the trap again in spring 2008. For more information on this project, please call WCWC at 541-846-9175. Volunteers remove fish from the smolt trap. After the fish are identified and measured, their fins are marked to avoid double-counting. Trapped fish are identified, measured and counted. The trapped fish are all carefully returned to the creek. Arthur Sherman WCWC Council Coordinator 541-846-1024