Aspectos da reprodução e dinâmica populacional de Chione pubera (Bory Saint-Vicent) (Bivalvia, Veneridae) no sul do Brasil

Abstract

Material collected with a 2-meter wide beam trawl during eight surveys conducted from December 1995 to February 1997 was used for a first preliminary description of the reproduction and population dynamics of the edible venerid bivalve Chione pubera (Bory Saint-Vicent, 1827). Greatest catches were found between 30 to 35 meters depth, on fine sandy bottoms with a mud content lower than 10%. Dry weight meat condition index showed highest values during autumn and lowest values from winter to summer months. Histological analysis of gonadal tissue showed a continuous reproduction, with peaks of maturation on autumn and spring, Spawning was related with the increase of water temperature, that occurs twice a year in the region as a consequence of a particular hydrological characteristic of the inner continental shelf. Size frequency distribution showed a unique principal mode with slow if any displacement through time, indicating a long lived species.