Reproductive biology of the cockle Cerastoderma edule (Mollusca: Bivalvia) from two lagoons on the Moroccan Atlantic coast

Abstract

The reproductive cycle and gonad development of the edible cockle Cerastoderma edule was studied over a period of 15 months (December 2017–February 2019) at two Moroccan lagoons, namely, Oualidia Lagoon and Sidi Moussa Lagoon. The reproductive cycle for both populations was asynchronous. The initiation of gametogenesis started in winter (December) and the maturation stage was in spring (March) for both lagoons, while Oualidia’s cockle was distinguished by another phase of maturation in summer (June). Sidi Moussa population was characterized by a prolonged spawning period and short sexual resting period. Unlike C. edule of Oualidia Lagoon undergo two peaks of spawning, the first one during spring and the second during summer Condition and gonadal indexes showed seasonal variations and were significantly correlated with temperature and chlorophyll a, which acted as stimulus for spawning events.