Testing Methods for Estimating the Factor Power Correction Obtained from the Comparative Fishing Trial: C/V Playa de Menduíña Versus R/V Vizconde de Eza

Abstract

In May 2001, a comparative Fishing Trial was conducted by Spain between the old research vessel C/V Playa de Menduíña and the new research vessel R/V Vizconde de Eza in order to calibrate the new ship. The corresponding Factor Power Correction (FPC) and its confidence interval were calculated by six analytical methods proposed in the fisheries literature for American plaice: ratio of mean CPUE, linear regression model, generalized linear regression model by haul, generalized linear regression model by stratum, Kappenma's ratio of scale parameters and a lenght conversion method. We present the results of these calculations and the transformed biomass from the old vessel data by all the methods. The old vessel cathes were in order of three times more than the new vessel catches. The model proposed by Kappenman gave FPC values with the least variation, although his FPC estimation is lower than the rest of the models, so the transformed biomass is lower, too.