Seasonal Changes in Body Condition of White Crappies and Relations to Length and Growth in Melvern Reservoir, Kansas

Relative weights (Wr = 100 [fish weight/standard weight at length]) of white crappies Pomoxis annularis were monitored in Melvern Reservoir, Kansas, from May 1986 to November 1987 to establish size-related seasonal patterns in condition. For each month from May to November 1987, total length and monthly length increment were compared to Wr for individual fish of ages 1 and 2. Relative weights of white crappies 130–199 mm long and those 200–249 mm long both increased through spring and surpassed a mean Wr of 90 by July. After July, mean Wr for 130–199-mm fish progressively declined through fall to below 75. Mean Wr of 200–249-mm fish also declined after July, but rebounded by fall. Relative weights of white crappies 250–299 mm long decreased after spawning in May, but increased thereafter to November. Mean Wr values near 100 were maintained from November 1986 to May 1987. By the end of June, yearlings had completed 73% of their annual growth; Wr and length increment were directly related. However, by September, Wr and length increment of individual yearlings were inversely related; Wr and length were inversely related by October. Length and Wr of individual 2-year-olds were directly related from August to November; length increment and Wr were directly related from September to November. Body condition in fall will best reflect growth for sizes of fish that maintain or improve condition throughout the summer, especially if most growth occurs early in the season.