Evaluation of Channel Catfish Sampling Methods in Small Impoundments. Sport Fish Restoration Project F-1-R-50.

摘要

Channel catfish Ictalurus punctatus populations have been difficult to effectively sample in small impoundments across the Midwestern and southern United States. The objective of this study was to determine the best time and method for sampling these populations. I compared seasonal catch rates, length frequencies, and mortality of channel catfish captured in hoop nets (set singly and in tandem) and gill nets, and examined size bias of tandem hoop net sets. Catches and mortality of fishes other than catfish (bycatch) and turtles were also tracked. The best sampling method was 3-day tandem hoop net sets. This method produced higher catch rates than gill nets or single hoop net sets, provided unbiased size structure estimates for fish 250 mm (9.8 in) and larger, and caused little mortality of captured channel catfish and bycatch. Single hoop net and gill net catches exhibited a negative binomial distribution; most hoop net sets captured no channel catfish and bycatch. Turtle mortality commonly exceeded 50% in hoop net sets, especially in mid summer, but turtles were never captured in gill nets.