Reproductive activity and seasonal variability in the biochemical composition of a pen shell, Atrina maura

Abstract

Atrina maura is a bivalve in the family Pinnidae and is the most important pen shell species fished in Mexico. To date, there is no information on the effects of reproductive activity and environmental variables on the biochemical constituents of the body tissues of this species. To fill this gap, we studied the reproductive cycle of A. maura monthly during 2015. Total carbohydrate, lipid, and protein content of the muscle, mantle, gonad, and digestive gland were measured. Sea surface temperature and chlorophyll a concentration were obtained, and the interannual differences were calculated. The results indicate that warmer temperatures, influenced by El Niño, and food scarcity, influenced by ‘The Blob’ event, affected the reproductive activity of A. maura. Females exhibited massive oocyte degeneration and shorter reproductive events with intermittent spawning peaks, while males spawned continuously throughout the year but without a maturation stage. The biochemical composition indicates that this population relies on protein metabolism, with no difference between sexes. Temperature had a negative effect on lipid production by the digestive gland in females, while in males, carbohydrate content in the mantle was negatively affected by temperature. Food scarcity was only correlated with lower carbohydrate content in the digestive gland of females. The mantle and the digestive gland exhibited an important role during reproductive activity as a physiological adaptation to unfavorable environmental conditions such as warmer temperatures and food scarcity.