Population dynamics and life history traits of the commercially important jaguar round crab Xantho poressa (Olivi, 1792) in Gran Canaria’s Intertidal Zones (Spain)

Abstract

The jaguar round crab, Xantho poressa, is the most important bait shellfish species in the Canary Islands. The aim of the study was to assess the status and population structure of Xantho poressa in the island of Gran Canaria. Specimens of X. poressa were caught monthly between July 2020 and December 2021 in three intertidal areas with different fishing pressure. Males were consistently larger and heavier than females, and the sex ratio was not different to 1:1. Length-weight relationship showed a negative allometric growth pattern in both sexes, and no significant differences were found between the sampling areas on three sides of the island, suggesting the presence of a single population. Ovigerous females were observed throughout the year, with a peak between June and August, indicating a continuous reproductive cycle. The ELEFAN method estimated an asymptotic carapace length of 31.19 mm. Catch per unit effort showed notable differences between the sampled areas, being the highest abundances (10.42 g/m2/gatherer) recorded at the northern coast and the lowest (5.10 g/m2/gatherer) at the southern one. The relative low abundance, particularly in the south coast, in relation with the current allowed catch quotas (1500 g/day/gatherer for artisanal fishing, 200 g/day/gatherer for recreational fishing) and a high number of recreational fishing licenses, indicate that the jaguar round crab stock of the island could be in risk of overfishing. This analysis provided crucial biological information to support management and conservation strategies for X. poressa .