Red Snapper: Ecology and Fisheries in the U.S. Gulf of Mexico

Abstract

<em>Abstract.</em>—Red snapper <em>Lutjanus campechanus </em>sagittal otoliths were sampled from U.S. Gulf of Mexico commercial vertical hook and line, longline and recreational landings over a twelve year period (1991–2002). Our objectives were to examine the empirical age structure of red snapper through space and time, to gauge the relative year-class strength over time, and to compare the impact of strong year-classes upon annual age structure by fishing sector. The recreational fishery selected the youngest fish with a mode at 3 years and a mean age of 3.2 years. The commercial vertical hook and line fishery selected for slightly older fish with a mode of 3 years and a mean age of 4.1 years. The commercial longline fishery selected the oldest individuals with fish first fully recruited to the fishery by age 5 and, a mean age of 7.8 years. Only the commercial longline fishery age distributions were significantly different between the eastern and western Gulf of Mexico. Based on age progressions, strong 1989 and 1995 year-classes were dominant in the landings of the recreational and commercial vertical hook and line fisheries and the 1995 year-class was dominant in the commercial longline landings. A relative year-class index further highlighted these results, and we noted a significant correlation in year-class strength between recreational and commercial vertical hook and line sectors. The year-class index for combined sectors was also significantly correlated between eastern and western Gulf of Mexico with 1989 and 1995 year-classes similarly dominating both regions. An empirical age progression year-class index could be valuable in correlation with early life abundance indices of red snapper and serve to provide inference about the relative error of recruitment data.