Sutter et al.: Movement and stock affinities of Scomberomorus cavalla 



321 



F 17.382). Several fish moved remarkable distances 

 over short periods of time. For example, one fish re- 

 leased from Jupiter, Florida, traveled 2250 km in 77 

 days before being recaptured off the southern Texas 

 coast. 



King mackerel stocks 



in the southeastern United States 



The percentages of king mackerel released as either 

 Atlantic or Gulf stock and classified (using the posterior 

 probability of the discriminant function analysis) into 

 the same stock based on time and place of recapture 

 are given in Table 2. The chi-square value for the test 

 of homogeneity of the within-group covariance was 

 significant (x 2 41.89, df 6); therefore, the within- 

 covariance matrices were used in this analysis. A total 

 of 66.81% of king mackerel released as Atlantic stock 

 was classified as the same stock upon recapture; 

 therefore, this group was given a 66.81% affinity in- 

 dex value (Table 2). A 76.07% affinity index value was 

 found for the Gulf of Mexico king mackerel stock. The 

 percentage of classification for recaptured king 

 mackerel in the five substocks is given in Table 3, again 

 using the within-covariance matrices in the discrimi- 

 nant function Or 245.87, df 24). All fish released in the 

 SE U.S. Atlantic coast substock area were recaptured 

 within the temporal and spatial definition of the Atlan- 

 tic stock; i.e., they were all classified with either the 

 SE U.S. Atlantic coast or southern Florida summer 

 substocks (Table 3). Therefore, the SE U.S. Atlantic 



coast substock was given a 100% affinity value for the 

 Atlantic stock. Southern Florida summer substock 

 returns were similarly examined; 4.23% were classified 

 with the SE U.S. Atlantic coast substock, and 53.97% 

 were classified with the southern Florida summer 

 substock, which yielded a 58.20% affinity index value. 

 The combined Gulf substock had a 100% affinity-index 

 value for the Gulf stock based on returns from the 

 Florida Keys winter substock (9.09%) and from the 

 Gulf waters (90.91%). The affinity-index value of the 

 Florida Keys winter substock was 90.00% (Table 3), 

 although some fish released in this area were classified 

 in each of the five substock areas. King mackerel 



