2000 Warmwater Fish Survey of Silver Lake, Cowlitz County

Silver Lake was surveyed during the spring and fall of 2000. Spring sampling occurred between May 1-4, 2000, by all members of the Warmwater Enhancement Program (six electrofishing boats). Fall sampling occurred on October 18 and 19 by a 3-person team. Multiple gear types (electrofishing, gill nets, and trap nets) were utilized to reduce any sampling bias associated with each sampling method. The surveys were undertaken to track the rebuilding of the fish community after the breach of the dam on Outlet Creek, and subsequent draining of the lake. Sample sizes for most species were very low (total 2,800 fish for spring and 472 fish for fall). Stock density indices show a lack of smaller fish, with higher abundances of fish quality sized and larger. The 1998 year class of many species is either missing or greatly reduced. The dam breach had a definite effect on the fish community as a whole, but no supplemental stocking is recommended at this time. Instead, recommendations for Silver Lake include: 1.) an angler creel survey to estimate angler preference, effort, and harvest ; 2.) continued fish community surveys during both spring and fall seasons to track population rebuilding; and 3.) continued grass carp population monitoring and, if possible, vegetation assessments.