TRENT ET AL.: KING MACKEREL IN SOUTHEASTERN UNITED STATES 



TABLE 3. — Mean length (mm, x), modal length (mm, ML), and per- 

 cent female (%F) of king mackerel samples by area, gear type, and 

 month during 1968-69 and 1975-76. 



Year 



Recreational 

 hook and line 



Commercial 

 hook and line 



Gill net 



ranged from 57.1 to 75.8. Only in south Florida did 

 the sex ratio favor males; during 1978 the annual 

 estimate based on commercial hook-and-line data 

 was 40.2% females. Sex data were available from all 

 seven areas in 1978; percent female ranged from 40.2 

 in south Florida to 92.9 in Louisiana (Table 5). 



The degree of dominance by female king mackerel 

 varied in relation to size of fish and type of capture 

 gear (Table 5). Females were dominant in all size 

 classes >900 mm FL and were dominant in 31 of 38 

 sample groups at lengths <900 mm FL. 



COMPARISONS AMONG 

 GEAR TYPES 



An understanding of the variations in fishing techni- 

 ques with a particular gear, and of the selective 

 characteristics of each gear, is needed to interpret 

 our data properly in making comparisons of size com- 

 position among years and geographic areas. The 

 baits used by recreational fishermen in various areas 



1300 

 1200 

 1100 

 1000 

 900 

 800 



s 



(!) 



5 900 



ac 



2 800 



700 



600 



900 



LOUISIANA 



,•77 



TEXAS 



800 



700 



NORTHWEST 

 FLORIDA 



SOUTH FLORIDA 



i i 



E— « 



JAN. MAR. MAY JUL. SEP. NOV. 

 MONTHS 



FIGURE 2. — Monthly mean fork lengths of king mackerel, Scom- 

 beromorus cavalla, caught by recreational hook and line by year 

 and area. 



are described above. Since data are not available for 

 evaluating variations in recreational fishing techni- 

 ques and their selectivity for particular sizes of fish, 

 we assumed that the various baits and methods were 

 not sufficiently selective to bias our analyses to this 

 point. We did, however, have data to evaluate size 

 selection among recreational hook and line, commer- 

 cial hook and line, and gill nets. 



Time, area, and sample size were used as criteria to 

 select data for comparison. A minimum of 25 fish was 

 required from the same geographic area during the 

 same month from each of two compared gear types. 



713 



