2004 Warmwater Fisheries Survey of Box Canyon Reservoir, Pend Oreille

Box Canyon Reservoir is an 88 kilometer stretch of the Pend Oreille River between Albeni Falls Dam near Newport and Box Canyon Dam near Metaline Falls in Washington State. On May 10-14, 2004 a warmwater fisheries survey was conducted through a joint effort by the Washington Department of Fish and Wildlife, the Kalispel Tribe of Indians’ Natural Resources Department, and Eastern Washington University’s fisheries program. During the weeklong effort, eight three-person crews sampled 128 of 644 available 400 meter shoreline sections by nighttime boat electrofishing, 56 by gillnetting, and 64 by fykenetting. Data collection included identifying all fish captured to species and recording total length (mm) and weight (g) from fish collected. Additionally, scales were collected from up to five fish per 10 mm length group for age and growth analysis. A total of 15,525 fish, comprised of 24 species, were collected. Pumpkinseed sunfish Lepomis gibbosus (28% by number), yellow perch Perca flavescens (27%), largemouth bass Micropterus salmoides (8%) and black crappie Pomoxis nigromaculatus (6%) were the most numerous warmwater game fish species sampled. Northern pikeminnow Ptychocheilus oregonensis (11% by number), peamouth Mylocheilus caurinus (7%), and tench Tinca tinca (6%) were also numerous. By weight, Tench (33%), largescale sucker Catostomus macrocheilus (12%), and largemouth bass (12%) accounted for the majority of the catch. Boat electrofishing catch rates were highest for pumpkinseed sunfish and yellow perch, followed by northern pikeminnow and largemouth bass; gill net catch rates were highest for peamouth and yellow perch; and fyke net catch rates were highest for pumpkinseed sunfish, yellow perch, and tench. The size ranges (mm; total length) of warmwater game fish sampled were: largemouth bass (52-534), smallmouth bass M. dolomieui (65-431), black crappie (35-280), yellow perch (45-246), pumpkinseed sunfish (29-199), brown bullhead Ameiurus nebulosus (72- 324), and northern pike Esox lucius (267-860). Population indices, including proportional stock density, relative weight, and growth rates, all indicate a prey-crowded community. The results of this survey, when compared with previous work, indicate little change in the reservoir’s fish community over the past 15 years. However, a recent increase in the occurrence of northern pike, in angler reports and fishery sampling efforts, warrants careful monitoring of the population. Managing the reservoir’s warmwater fish populations for quality bass angling opportunity continues to be a viable option for fishery managers.