Reproductive Dynamics and Hermaphroditism in the Black-Footed Limpet (<i>Patella depressa</i> Pennant, 1777) on an Intertidal Rocky Shore in the Algarve Coast (Southern Portugal)

The present study aimed to describe the reproductive cycle of the black-footed limpet (Patella depressa Pennant, 1777) from an intertidal rocky shore in the Algarve coast (southern Portugal). Samples were collected monthly between January 2017 and December 2018, being the species gametogenic cycle described based on gonad histology and the mean gonadal index. The presence of both transitional and mosaic hermaphrodites, indicate that some individuals are able to change sex (sequential hermaphroditism). Despite the occurrence of hermaphroditism, sex proportions were approximately equal, suggesting the absence of protandric sex change in this species. The population exhibited an extensive occurrence of ripe and spawning gonads, throughout almost all study period, probably related to consecutive processes of gonadal re-ripening and partial spawning events. The reproductive dynamics of P. depressa displayed clear inter-annual differences, with a short resting period recorded in 2017 (June &ndash; August) and the absence of resting gonads in 2018. Continued monitoring of this population and collection of environmental data is required to further improve the knowledge on the reproductive dynamics of this species. Such information is crucial for proposing additional management measures for the sustainable recreational harvesting of limpets in southern Portugal.