Seasonal Variation in Catch Rate and Body Condition for Four Fish Species in a South Dakota Natural Lake

ABSTRACT

Seasonal variation in catch rate (catch per unit effort, CPUE) and body condition (relative weight, Wr) for northern pike Esox lucius, black crappie Pomoxis nigromaculatus, yellow perch Perca flavescens, and walleye Stizostedion vitreum sampled with trap (modified fyke) nets was evaluated in Lake Madison, a natural lake in eastern South Dakota, from March through October, 1990. Seasonal variation in CPUE and Wr occurred for all fish species. Northern pike CPUE declined from spring until fall. Black crappie CPUE was highest in the spring and fall. Yellow perch and walleye CPUE peaked during the summer. Seasonal variation in mean Wrwas similar for all fish species—mean Wr declined from spring to early summer then increased until early fall. Fisheries biologists should consider seasonal variation associated with CPUE and Wr during the assessment of sampling data.