Standardization of the catch per unit effort (CPUE) of the industrial purse seine fleet extracting the north-center stock of the Peruvian anchovy (Engraulis ringens Jenyns)

Abstract

We used a methodology based on Generalized Linear Model(GLM). The CPUE was expressed as metric tons of catch per trip duration. The explicative variables used were year, month, holding capacity, latitude, spatial inertia and distance from the coast. The model had a determination coefficient of 0.485, explaining almost half of the variability observed in the CPUE. The variable with the highest influence was the holding capacity (49% of the explained variance), likely due to the high harvest capacity of the anchovy fleet and the hyper-aggregation of the pelagic resources, which occurs even if they are highly exploited. The correlation between the standardized CPUE and estimated biomass from a catch-at-age model (r=0.74) indicates that the method based on GLM is recommendable for the standardization of CPUE. The resultant CPUE is proposed as an alternative for monitoring the anchovy biomass.