Ecological Benchmarking to Explore Alternative Fishing Schemes to Protect Endangered Species by Substitution: The Danish Demersal Fishery in the North Sea

The cod stock in the North Sea is threatened by overexploitation. To recover this fishing stock, pressure needs to be reduced. This implies that catch compositions with small amounts of cod are preferred by public policy makers. The present analysis assesses the technological efficiency of fishing trips in terms of the substitution possibilities away from cod by considering landings of cod as an undesirable output. A conservative non-parametric frontier technology approach imposing minimal assumptions and based on directional distance functions is applied to explore alternative fishing activities for Danish gill netters operating in the North Sea with the goal of reducing cod catches. Since performance on different fishing trips may be influenced by the operating environment, a four-stage approach is applied to correct for exogenous factors (Fried et al., J Product Anal 12(3):249–267, 1999). The corrected directional distance function efficiency scores reveal the behavioural inefficiencies, i.e., prospects for decreasing the catch of cod while catch of other species are increased.