Comparison of Catch per Unit Effort and Size Structure of White Crappies Collected with Trap Nets and Gill Nets

摘要

White crappies Pomoxis annularis were collected from 13 Kansas reservoirs with trap nets and horizontal gill nets. Ten of the reservoirs were sampled concurrently for two or more years. Our objective was to determine if catch per unit effort (CPUE)—the number of stock-length (>=13-cm) white crappies captured per trap-net-night or per gill-net-complement-night— and size structure—indexed by measures of stock density—differed between trap nets and gill nets. We found no significant relation betweentrap-net and gill-net logio(CPUE). Conversely, size structure of white crappies was similar between gears. Proportional stock density (PSD) and relative stock density of preferred-length fish were positively correlated between gears. Relative stock densities by length category were also significantly correlated between gears. These data indicate that the two gears likely would give similar information about changes in white crappie population size structure, but disparate information about the species' relative abundance.