Comparison of Catches in Mono- and Multifilament Gill Nets in Lake Erie

The purpose of this study was to compare the number, age, sex, and size offish caught in mono- and multifilament gill nets used to assess populations in Lake Erie, The results of this study could be used to adjust estimates of catch per unit of effort if there were a change from multifilament to monofilament gill nets. More yellow perch Perca flavescens (ratio of catches in mono- and multifilament gill nets = 2.04/1), white bass Morone chrysops (2.78/1), white perch Morone americana (2.07/1), freshwater drums Aplodinotus grunniens (2.93/1), walleyes Stizostedion vitreum (1.92/1), and white suckers Catostomus commersoni (1.23/1) were caught in monofilament gill nets. Only rainbow smelt Osmerus mordax and silver chub Macrhybopsis storeriana were more catchable in multifilament nets. There was some evidence that white perch and freshwater drum saturate monofilament gill nets more than multifilament nets. Age, size, and gender compositions of the catches were similar for both gears. Previously, catches in multifilament nets were compared with monofilament catches by applying a ratio of catches in the two gears. Before making these adjustments, one should ensure first that the ratio is statistically significant, and second that the catches of individual species are not affected by other species saturating the gear.