LIFE hISTORy OF RE d gROUpER (EpinEphElu S Morio) OFF ThE COASTS OF NORTh CAROLINA ANd SOUTh CAROLINA

Abstract

The objective of this research was to update the knowledge on the life history of red grouper Epinephelus morio (Valenciennes in Cuvier and Valenciennes, 1828), a commercially important species off North Carolina and South Carolina. A total of 2146 specimens was sampled from commercial catches and obtained with fisheryindependent gear between december 1996 and September 1999. Red grouper ranged in total length (TL) and age from 315 to 851 mm and from 2 to 20 yrs. Observed length-at-age was described by the following von Bertalanffy growth equation: TL (mm) = 853(1−exp ( −0.209(age (yr)+0.812))). Sex and reproductive state of 2068 red grouper were assessed by histological analysis. Of these, 86.8% were classified as female, 5.9% as transitional, and 7.3 % as male. Age at 50% maturity was 2.4 yrs and TL at 50% maturity was 487 mm. The sex ratio of red grouper was 1 male to 6.6 fe males. Red grouper was confirmed to be a protogynous hermaphrodite. Age at 50% transition was 7.2 yrs and TL at 50% transition was 690 mm. Spawning in females occurred between mid-February and mid-June. Spawning females were captured on multiple locations off the North Carolina and South Carolina coasts, at depths between 33 and 90 m.