The present study reports a detailed description of the reproductive cycle of the common limpet (Patella vulgata) and rough limpet (Patella ulyssiponensis) from Praia da Luz in Lagos (Algarve coast – southern Portugal). Individuals of both species were sampled monthly from intertidal rocky areas during two consecutive years (January 2017 – December 2018) and subjected to gonad histology and calculation of the mean gonadal index (GI). In these protandrous hermaphrodite limpets, the estimated size at sex change was slightly smaller in P. vulgata (SL50 ≈ 29 mm) than in P. ulyssiponensis (SL50 ≈ 36 mm). In general, the reproductive cycles of both species were characterised by a main spawning season in early spring – early summer, sometimes including subsidiary spawning events, followed by a short resting period during summer. The comparison of the main spawning season throughout the species distributional ranges revealed that populations of P. vulgata and P. ulyssiponensis from southern Portugal have the later spawning period reported for the northeastern Atlantic Ocean. The overall information gathered in this study is relevant for conservation purposes and provides valuable baseline data for the proposal of management measures for the harvesting activity targeting P. vulgata and P. ulyssiponensis in southern Portugal.
Managing Thesis and Internship Exchanges
