Intra- and Interannual Variation in the Relative Condition and Proximate Body Composition of Arctic Ciscoes from the Prudhoe Bay Region of Alaska

Abstract

Abstract Weight and length data collected during the summers from 1984 through 1994 were used to examine the seasonal life history strategy of Arctic ciscoes Coregonus autumnalis collected from Prudhoe Bay, Alaska. Differences in observed and predicted weight were used to determine if condition increases during the summer feeding season when energy reserves are accumulated and decreases during winter when energy reserves are depleted. Data from proximate body analyses of lipid and protein content collected from 1991 to 1993 also were examined. Condition was indexed as residual values generated from a whole population least-squares regression of log e -transformed weight and length data. For data pooled by individual year-classes, we tested the conceptual hypothesis that mean residual value, mean lipid content, and mean protein content increased during summer and decreased during winter. For the 12 year-classes examined, concurrent mean residual values supported our conceptual hypothesis in 61 of 76 instan...