Demographics and Yield–Per–Recruit Assessment of the Vulnerable Spiny Lobster <i>Palinurus elephas</i> in the Azores—Implications for Conservation and Fisheries Management

Abstract

The spiny lobster Palinurus elephas has been intensively harvested across its range and is generally considered overfished, with global landings declining sharply from an average of 820 t in 1960–79 to 385 t in 2000–19. Despite its economic and ecological importance, limited information is available to perform stock assessments and make robust management decisions. In this study, demographics and exploitation levels of P. elephas were determined from coastal areas of the Azores, and the relevance of these data for conservation planning was discussed. Carapace length varied between 39.6 and 174.3 mm, with mean sizes decreasing by depth. Males reached larger sizes and grew faster than females but were less dominant. Lifespan was 43 years for females and 60 years for males. The estimated mean length at first capture was 101.65 mm—around 58% of its asymptotic length. Fishing mortality and exploitation levels were close to the optimal values, indicating an uncertain future for Azorean populations if stock assessment and management initiatives are not focused on this species. Conservation and management strategies may benefit from these results under the ‘precautionary approach’ principle. However, up–to–date and accurate catch and fishing effort data need to be urgently collected.

Keywords

• crustacean
• commercial species
• data-limited
• life-history
• population structure
• exploitation level