BECKMAN ET AL.: AGE AND GROWTH OF RED DRUM 



Comparison of age distributions between years 

 provided two estimates of the population age-class 

 structure, varying in time and areas sampled. The 

 similarities in year-of-birth distributions in 1985-86 

 and 1986-87 suggest that the same population was 

 sampled in both years and that distributions may 

 reflect the true offshore schooling population of red 

 drum, assuming no sampling selectivity. Recruit- 

 ment into the population from one year to the next 

 was evident only in the youngest age classes, 

 possibly due to migration from inshore nursery 

 areas. The relatively low numbers of individuals in 

 age classes of less than 10 or 11 years suggests a 

 possible delay or reduction in recruitment into the 

 schooling population sampled. Other possible factors 

 affecting abundance of younger age classes offshore 

 are fishing pressure on inshore red drum, size 

 specific fishing offshore, or other factors affecting 

 survival. 



ACKNOWLEDGMENTS 



Sampling efforts were supported by the Louisiana 

 Sea Grant College Program; the U.S. Department 

 of Commerce, NOAA, Marine Fisheries Initiative 

 Program (MARFIN); the Louisiana State Univer- 

 sity, Coastal Fisheries Institute; the Louisiana 

 Department of Wildlife and Fisheries; and the Na- 

 tional Marine Fisheries Service. Sampling involved 

 the cooperation of many recreational and commer- 

 cial fishermen. We thank Gary Fitzhugh, Bruce 

 Thompson, David Nieland, Robby Parker, David 

 Stanley, and Tony Gaspard for their assistance in 

 data collection and analysis, and James Geaghan for 

 statistical assistance. 



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