Sampling Littoral Fish with a Seine: Corrections for Variable Capture Efficiency

Capture efficiency of a beach seine varies greatly depending on aspects of the littoral zone habitat and fish community. To address this sampling bias, we quantified seine efficiency and several habitat and fish community variables at 26 littoral stations in 10 southern Quebec lakes. We then generated regression models predicting capture efficiencies for total, midwater, and benthic fish. Predictions from these models yield "sliding" correction factors for seine catches. Bottom snags and seine rolling generally reduced capture efficiencies, and higher proportions of benthic fish were associated with reduced capture efficiencies for total fish. Higher macrophyte biomass was associated with increased capture efficiencies. Fish size was a significant predictor of capture efficiency only for benthic fish; smaller fish escaped the seine more readily. Regression models explained 26–73% of the observed variation in capture efficiency. Use of our models will improve the accuracy of abundance estimates from littoral seining with little additional effort.