Evaluation of the bait crabs resources exploited by shellfish gathering in the Canary islands

Abstract

The assessment of populations of the bait crabs Xantho spp., Pachygrapsus spp. and Percnon gibbesi is carried out for the first time for Gran Canaria Island in order to establish their current status. Their respective reproductive periods are described and, according to this, is proposing a modification of the temporary closures of the gathering fishery. The study analysed 3 shellfish areas, at south, east and north of the island. The catch per unit of effort (CPUE) values for Pachygrapsus spp. and Percnon gibbesi were the highest in the north (81.88±67.66 and 26.69±32.63 individuals/hour/gatherer, respectively). However, the highest values for Xantho spp. were obtained in the east coast (27.13±19.92 individuals/hour/gatherer). To establish a correct estimation of the CPUEs by areas, season and fishing effort, a Generalized Additive Model (GAM) was applied to estimate the fishing pressure on this crab species in each area and globally.