TRENT ET AL.: KING MACKEREL IN SOUTHEASTERN UNITED STATES 



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All data meeting the above criteria were from fish 

 caught off south Florida and North Carolina (Tables 

 1, 2) and are summarized in Table 6. 



All comparisons of south Florida frequency dis- 

 tributions (recreational hook and line to commercial 

 hook and line, and commercial hook and line to gill 

 net) showed significant differences between size 

 compostions; no significant differences were found in 

 comparisons of compositions from North Carolina. 

 The summary data (Table 6) from the south Florida 

 samples showed the following: 1) Mean lengths were 

 greater from gill nets than from commercial hook and 

 line in 5 of 6 cases, 2) standard deviations about the 

 mean were similar between gill nets and commercial 

 hook and line, and 3) frequency distributions were 

 slightly skewed to the right in 15 of 16 cases. 



Although no significant differences were found be- 

 tween the size-frequency distributions of the rec- 

 reational and commercial hook-and-line catches in 

 North Carolina (Table 6), the summary data showed 

 the mean size to be larger, and the standard deviation 

 about the mean to be smaller, in the recreational 

 catches. 



The frequency distributions, from which data in 

 Table 6 were computed, were converted to percent 

 frequency and averaged within gear type and year. 

 These distributions, summary statistics, and results 

 of chi- square comparisons are shown in Figure 3 and 

 Table 7. All comparisons between gear types were 

 significantly different. Mean lengths and standard 

 deviations were greater for the fish caught by gill nets 

 than by commercial hook and line during 1968 and 

 1977; the opposite was true for 1976. Mean lengths 

 of fish caught by recreational hook and line were 

 greater than those caught by commercial hook and 

 line in 1979 (south Florida) and by commercial hook 

 and line 1978 (North Carolina). 



The available data (above) were not adequate to 

 evaluate selectivity and did not reflect the wide 

 variations in mean and modal lengths that occurred 

 among months in the catches. When individual month- 

 ly modes are viewed, we see that modal lengths 

 varied from 649 to 849 mm FL in distributions from 

 commercial hook and line but were always 749 mm 

 FL in the gill net catches (Tables 3, 4). Modal lengths 

 from recreational hook-and-line catches showed 

 even more variation and ranged from 549 to 1,249 

 mm FL. 



Although selectivity of the gears could not be pro- 

 perly quantified, we concluded, based on fluc- 

 tuations (or lack of) in the modal lengths, that among 

 the three gear types the gill net is the most selective 

 and the recreational hook and line is the least selec- 

 tive toward sizes of king mackerel. 



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