Standardisation of commercial CPUE

A model for standardisation of fishing power for individual vessels in a commercial fishing fleet is developed. Catch rates of vessels are compared when they are fishing close together in time and space, and their fishing power relative to a standard vessel is calculated. The model is applied to a logbook data base from the Norwegian bottom trawler fleet, and effects of varying model parameters are explored. Relative fishing power from the model are correlated with the vessel’s length and engine power. The model seems to be robust when varying catch composition criteria, minimum number of comparisons required and standard vessel.