Biases and Utility of Tournament and Angler Catch Data for Assessing Population Structure Indices of Channel Catfish

in an Urban Lake

Authors: Randall D. Schultz and Benjamin J. Dodd

The utility and biases associated with angler harvest data of black bass for fishery management decisions has been shown to be useful, but little information exists on the utility of tournament and angler-catch data for monitoring channel catfish.  We compared sizes and numbers of channel catfish caught by small tournament anglers, creel-surveyed anglers, and baited tandem hoop nets in Lake Manawa, an 800 ac urban lake in Council Bluffs, Iowa.  Tournaments were conducted monthly from May – September, 2006 and the creel survey was conducted from April – October 2006.  Tournament catfish anglers, creel-surveyed anglers, and tandem-baited hoop nets all caught different sizes of channel catfish.  Mean total length of channel catfish caught was lowest in the tandem-baited hoop nets, intermediate for creel-surveyed anglers, and highest for tournament anglers.  Comparisons of angler and tandem-baited hoop net catch rates by size categories revealed that tournament anglers selected against small channel catfish (i.e., RSD S-Q: 28-41 cm); otherwise comparisons among anglers and tandem-baited hoop nets were similar.  We believe there is some utility and cost-savings benefits associated with using angler-caught channel catfish data for making management decisions, but biases need to be considered and more information on comparisons between angler caught channel catfish and sampling data are warranted.