Diel and Seasonal Variation in Foraging Activities of Pumpkinseeds in an Ontario Pond

Abstract

Abstract We used time-lapse video with infrared illumination to record feeding activity of pumpkinseeds Lepomis gibbosus in two patches of littoral habitat in a shallow, mesotrophic Ontario pond. Observations were made for 72 consecutive hours in each of eight ice-free months and include extensive, relatively nonintrusive field observations of pumpkinseed behavior at night. We tallied numbers of passes above the substrate and numbers of substrate strikes (at substrate or at vegetation). Variation among months accounted for 40–50% of the total variation in rates of daytime passing and substrate striking, which peaked in May and September. Among-day variation in daytime foraging activity within months was high, accounting for 50–57% of the total variance, and the variances we measured can be used to plan replication levels necessary to achieve adequate statistical power in future studies involving measurements of daily ration or comparisons of exploitation rates in different habitats. Simultaneous video mon...