BIOMETRIC VARIATION AND REPRODUCTION OF THE BIVALVE Anomalocarida flexuosa (BIVALVIA; VENERIDAE) IN DIFFERENT FISHING AREAS

The bivalve Anomalocardia flexuosa is one of the main fishing resources utilized in artisanal fishing in northeastern Brazil. The objective of the study was to identify the reproductive and biometric variations in the A. flexuosa shell across different fishing areas in the estuary of the Goiana and Megaó rivers in Northeast Brazil, generating information to support strategies for its conservation. Three bimonthly sampling points were used, with P1 being characterized by manual fishing; P2 by more intensive fishing than P1, with the use of less potent fishing gear; and P3 by high-intensity fishing with tools that enhance the collection capacity, such as long-handled nets. For each specimen collected, shell length, shell height, shell width, total weight wet weight, and meat yield were measured to assess size patterns of the organisms and meat yield. Histological analyses were also conducted to identify the reproductive stages. From the analysis of 5,188 captured specimens, it was observed that with P3 presented the lowest body sizes, possibly reflecting overfishing at the site. Growth models were isometric for shell measurements and negative allometric for the length-weight relationship in P1 and P2, and positive allometric in P3. Photomicrographs were taken of 32 specimens for P1, withe 45% males, 48% females and 7% unidentified; and 25 specimens in P3, 12% males, 52% females and 36% unidentified. Regarding reproductive stages, the most representative were the “maturation” and “mature” stages. Due to the evidence of overfishing in P3 and high potential yield in other points, we highlight the need for efficient management actions that mitigate the impacts of overfishing, such as rotation of fishing areas.