Objective: To enhance the reliability of fishery-dependent data and improve our understanding about possible injuries caused by recreational angling gear from a welfare perspective, an understanding of the social and gear-related determinants of catch rates and injury rates is of critical importance. We experimentally assessed the impact of angler skill and different hook sizes on fish catch, hooking depth, and bleeding status in recreational pole fishing of small-bodied freshwater fish.
Methods: In fully controlled experimental field studies, we captured close to 2,000 fish and evaluated the effects of angler skill and hook size on catch outcomes and injury (hooking depth and bleeding) in pole fishing for small-bodied freshwater fish (primarily cyprinids). The experiments followed a factorial randomized block design over 3 years (2011, 2020, and 2024) at two water bodies in northeastern Germany. Individual angler skill levels were determined using a set of self-reported angling skill questions administered before experimental sessions started. We examined whether this self-reported skill index predicted actual catch outcomes (i.e., actual skill) while controlling for site and key gear components.
Results: Anglers self-identifying as skilled indeed achieved significantly greater catch per unit effort (CPUE) than unskilled anglers (a twofold difference on average). Angler skill was unrelated to the size of fish captured. Unskilled anglers caused more fish bleeding than skilled anglers, but the depth of hooking did not vary with the self-reported angling skill index. Hook size (J-hooks ranging in size from 10 to 18) did not influence CPUE or fish injury.
Conclusions: We found a strong skill effect in experimental pole fishing for freshwater cyprinids. Quantifying and statistically considering self-perceived angler skill in future creel surveys and engaging in CPUE standardization when analyzing time series of observational CPUE data collected from angler populations using a self-reported skill index would improve the accuracy of fish stock assessments that use fishery-dependent data collected from anglers.