The North Carolina Wildlife Resources Commission initiated a fall crappie (Pomoxis spp.) trap net-based stock assessment program in 1986. Since 1986, declining catch rates have forced increased effort to meet sample size requirements. The objective of this study was to determine the effect of trap net design on crappie capture rates and size selectivity. In March and April 1998, 5 trap nets each of 3 mesh sizes (13, 19, and 25 mm bar measure) were set overnight (24 hours) for 4 consecutive nights on 3 piedmont North Carolina reservoirs. Catch rates of crappie approximately doubled with each increase in mesh size and were significantly (P < 0.05) different among all mesh sizes. Similar results were found for crappie <250 and ≥ 250 mm total length (TL). Differences in the pooled length frequencies of the catch were found among mesh sizes; however stock length fish (≥130 mm) were vulnerable to each mesh size and the size range of crappies collected appeared similar among meshes. Increasing mesh size from 13 to 25 mm appears to offer fishery managers a way to significantly increase trap net catches for stock size crappie and control sampling effort. Catch rate and size distribution information collected with the larger mesh traps will not be directly comparable to similar information collected with the smaller mesh traps.
