Abstract

Based on estimation of age structure from catches derived from the west Florida shelf, gag (Mycteroperca microlepis) stocks exhibit alternating strong and weak year classes. Four year classes (1985, 1989, 1993, 1996) were observed to exceed 40% of the total annual age structure by ages 4 - 6, the ages at full recruitment to the fishery. When sample locations were more precisely reported during 1998 - 1999, there was a slight trend towards older ages and increased ratio of males from the southwest Florida coast versus north of Tampa, the area where the fishery has historically been concentrated. The intluence of gear on age-structure was quite apparent. In general, recreational hook-and-line gear captured the youngest fish, with increasingproportions of olderages occurringincommercialhook-and-line and long-line gears. Because of the catch patterns resuling from a strong 1993 year class, we suggest that gear selectivity by age is determined more by location and depths fished relative to the population distribution and less due to direct attributes of the gear, such as hook size or differences in fish behavior and susceptibility by size.

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