Alternate Title

Age-Size Structure of Red Grouper, (Epinephelus morlo), from the Eastern Gulf of Mexico


Sagittal otoliths from 534 red grouper, Eplnephelus morlo, were collected from recreational and commercial fisheries of the eastern Gulf of Mexico in 1979-1981 (236 fish) and 1991-1992 (298 fish). Age estimations for the two collections were made In 1991-1992 from the surface and transverse sections of these otoliths. Also, estimates of back-calculated size at age (using the final annulus present at time of capture following Lea's (1910) method were made for these collections. Red grouper were larger in size at capture at age and back-calculated size at age in 1991-1992 than in 1979-1981. The respective von Bertalanffy growth parameters were:

1979·81 L∞ = 78.9, K = 0.1778, t0 = 0.8259
1991·92 L∞ = 92.6, K = 0.1588, t0 = 0.9323
where L∞ Is mean maximum attainable total length In centimeters, K Is growth coefficient, and t0 Is hypothetical age in years at which fish would have zero length.