2002 Warmwater Fisheries Survey of Pierre Lake, Stevens County, Washington

Pierre Lake (Stevens County) was surveyed by a 3-person investigation team June 11-14, 2002. Fish were sampled by boat electrofishing, gill netting, and fyke netting. Eight fish species were collected. Green sunfish (Lepomis cyanellus) (n=1,453) and largemouth bass (Micropterus salmoides) (n=816) were the most abundant species sampled during collection activities. Largemouth bass and green sunfish contributed the highest (48%), and second-highest (36%) proportion of the biomass, respectively. Brown bullhead (Ameiurus nebulosus), black crappie (Pomoxis nigromaculatus), cutthroat trout (Oncorhynchus clarkii), kokanee (O. nerka), rainbow trout (O. mykiss), and walleye (Stizostedion vitreum) were also collected. Although a small proportion of green sunfish in Pierre Lake have grown larger than is commonly seen in most northern waters, most are too small to provide much angling value. Slow growth, low condition, and missing year classes of black crappie, and low condition of smaller size largemouth bass may be a result of heavy interspecific competition with the relatively high density population of green sunfish. Largemouth bass up to 19 inches were observed in Pierre Lake, though most were smaller than 10 inches. Although populations of salmonid species appeared low, their numbers were most likely under represented because of sampling bias. Cutthroat trout observed during this survey were below the national average in terms of condition. Given its northern latitude, habitat characteristics, and history as a successful salmonid water, Pierre Lake may be best suited as a water managed for trout and kokanee and rehabilitation should be considered. If Pierre Lake continues to be managed as a mixed species water, future management considerations should include monitoring the response of fish populations to the recently imposed largemouth bass slot-limit, and conducting a creel survey to determine angler harvest and preferences.