SIZE, SEX RATIO, AND RECRUITMENT IN VARIOUS FISHERIES 



OF KING MACKEREL, SCOMBEROMORUS CAVALLA, IN 



THE SOUTHEASTERN UNITED STATES 



Lee Trent,' Roy 0. Williams, 2 Ronald G. Taylor, 2 

 CarlH. Saloman, 1 and Charles H. Manooch IIP 



ABSTRACT 



Data from over 54,000 king mackerel, Scomberomorus cavalla, were analyzed to evaluate spatial and tem- 

 poral variations in size and sex composition in seven areas of the southeastern United States. Data were 

 obtained from the recreational hook-and-line fishery of coastal states from Texas to North Carolina and from 

 commercial hook-and-line and gill net fisheries of south Florida. Of the three types of gear, recreational hook 

 and line appeared to be the least selective and gill net the most selective for particular sizes of king 

 mackerel. 



Size composition in each area varied considerably among months; patterns of size change were discernible 

 in some areas. Sizes of king mackerel varied significantly among areas and years. Catches from south and 

 northwest Florida contained high proportions of small fish (< 700 mmFL); those from Texas and North Car- 

 olina contained mostly medium-sized fish (700-900 mm FL). Mean lengths of king mackerel were larger in 

 1978 than in 1977 in all areas except northwest Florida. In northwest Florida, modal fork lengths were 749 

 mm in 1968-69, 649 mm in 1977, and 549 mm in 1978. The majority of the smallest fish (400-600 mm FL) 

 were recruited to the fisheries in Florida, but the range and areas ol abundance of king mackerel smaller than 

 this are not known. For purposes of evaluating effects of minimum size regi ilations, the king mackerel popula- 

 tion was divided into groups (the Florida winter, immature, spawning, and Louisiana groups). 



Females dominated catches in all size groups and in all areas and years, except for south Florida in 1978. 

 Annual, or ranges of annual, estimates of percentage female by area were as follows: Texas, 60.8-62.2 '.', ; 

 Louisiana, 91.9-92.2%; northwest Florida, 57.1-75.1%; south Florida, 40.2-75.4%; and North Carolina, 

 75.8' r . Females predominated in 3 1 of 38 sample groups at lengths < 900 mm FL. and in all sample groups at 

 lengths > 899 mm FL. 



The king mackerel, Scomberomorus cavalla, is one of 

 the most important species in the coastal pelagic 

 fisheries of the southeastern United States. Despite 

 its high commercial and recreational value (Deuel 

 and Clark 1968; Wise and Thompson 1977), many 

 details pertaining to king mackerel catches and pop- 

 ulation structure are not available. Information 

 needs include the following: 1) Seasonal size com- 

 positions by geographic area, 2) sizes and sex ratios 

 of king mackerel caught throughout the southeastern 

 United States, and 3) the number of groups support- 

 ing the fisheries. To meet these needs we 1) sum- 

 marized data from previous analyses (Trent et aL 

 1981) on seasonal changes in size and sex com- 

 positions of king mackerel catches, 2) determined 

 size and sex compositions in catches by capture gear, 

 area, and year, and 3) separated the stock(s) into four 



'Southeast Fisheries Center Panama City Laboratory, National 

 Marine Fisheries Service, NOAA, 3500 Delwood Beach Road, Pan- 

 ama City, FL 32407. 



: Florida Department of Natural Resources, 100 Eighth Ave., SE, 

 St. Petersburg, FL 33701. 



"Southeast Fisheries Center Beaufort Laboratory, National 

 Marine Fisheries Service, NOAA, Beaufort, NC 28516. 



groups for the purpose of evaluating minimum size 

 regulations in the fisheries. 



This undertaking is complicated by the widespread 

 nature of the species and by the diversity of various 

 fisheries harvesting it. King mackerel occur from the 

 Gulf of Maine to Brazil and are common in the Carib- 

 bean and Gulf of Mexico (Randall 1968). The number 

 of populations or stocks is unknown. The stock(s) 

 fished off the continental United States are probably 

 not the same as those fished in the Caribbean 

 because, of over 1,100 tag returns from over 14,000 

 king mackerel tagged in the southeastern United 

 States, not a single return came from the Caribbean. 4 

 In U.S. waters north of North Carolina, king mackerel 

 is not a target species, either commercially or rec- 

 reationally. The fish are highly migratory and the rec- 

 reational fishing effort for them in any given area is 

 directly related to their availability. Recreational 

 fishing effort is exerted along the Atlantic and 

 northern Gulf of Mexico coasts during the warmer 



Manuscript accepted February 1983. 

 FISHERY BULLETIN: VOL.' 81, NO. 4. 1983. 



4 R. O. Williams, Florida Department of Natural Resources, 100 

 Eighth Ave., SE, St. Petersburg, FL 33701, pers, commun., 

 August 1982. 



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