2002 Warmwater Fisheries Survey of Fish Lake, Chelan County, Washington

Fish Lake, Chelan County, Washington was sampled between September 23-27, 2002, using a boat electofisher, gill nets, and fyke nets. Eight fish species were observed during sampling efforts. Largemouth bass (Micropterus salmoides), yellow perch (Perca flavescens), rainbow trout (Oncorhyncus mykiss), brown trout (Salmo trutta), largescale sucker (Catostomus macrocheilus), northern pikeminnow (Ptychocheilus oregonensis), prickly sculpin (Cottus asper), and redside shiner (Richardsonius balteatus) were collected during this survey. Rainbow trout comprised the majority of the fish captured at Fish Lake, while warmwater gamefish, primarily yellow perch comprised 29.8 percent of the fish collected. Largescale sucker comprised 48.5 percent of the total biomass of fish collected, while rainbow trout comprised 21.6 percent of the biomass of fish collected.

Yellow perch ranged in age from one to eight years; however, Ages five and seven yellow perch were absent from our sampling. The PSD for yellow perch was 20, and relative weights were near the national average (Wr = 100). Growth of yellow perch was above the state average for all but age one fish.

Fish Lake is primarily managed as a trout fishery. Yellow perch are also sought after by anglers year-round. Historically, this lake provided excellent perch fishing; however, recently anglers have expressed concern over declines in harvest during the summer. No creel surveys have been conducted on this lake; therefore, no data exist on perch exploitation. This survey was conducted, in part, to determine the size structure and abundance of yellow perch in the lake. We found YOY and age one fish to be smaller than average for this time of year. It is possible that rainbow trout are competing with yellow perch for forage as well as preying on yellow perch YOY and juveniles. However, without any analysis of trout diets this remains unknown.