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Fishery Bulletin 117(3) 
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8 
Map of study area showing the 18 genetic sample groupings used in analyses for cobia (Rachycen- 
tron canadum ) collected in the Atlantic Ocean off the southeastern United States during 1988- 
2017. Groupings were determined on the basis of natural latitudinal breaks in the collection data. 
Abbreviations for group locations are given in Table 2. 
Table 3 
Mean fork length (FL) at tagging, by tagging zone, of cobia 
(Rachycentron canadum) sampled from 1988 through 
2017. The tagging zones of Georgia (n=l) and north of 
Brevard County, Florida (n= 2), were excluded because of 
small sample sizes. Standard deviations (SDs) are given 
for means. GOM=Gulf of Mexico. 
Tagging zone 
Mean FL (mm) 
Virginia 
853 (SD 9) 
North Carolina 
803 (SD 19) 
South Carolina 
825 (SD 10) 
Brevard County 
774 (SD 15) 
South of Brevard 
740 (SD 30) 
Florida Keys 
750 (SD 6) 
GOM 
764 (SD 25) 
Total 
786 (SD 19) 
Table 4 
Mean fork length (FL) at recapture, by recapture zone, of 
cobia (Rachycentron canadum) sampled from 1988 through 
2017. The recapture zones of north of Virginia (sample size 
[ft]=2) and Georgia (n= 5) were excluded because of small 
sample sizes. Standard deviations (SDs) are given for 
means. GOM=Gulf of Mexico. 
Recapture zone 
Mean FL (mm) 
Virginia 
964 (SD 10) 
North Carolina 
1008 (SD 29) 
South Carolina 
985 (SD 13) 
North of Brevard 
957 (SD 19) 
Brevard 
921 (SD 21) 
South of Brevard 
972 (SD 20) 
Florida Keys 
903 (SD 8) 
GOM 
935 (SD 6) 
majority of South Carolina cobia were recaptured within 
the South Carolina zone (n=112, 87.5%) in subsequent 
years and in close proximity to the tagging location (Fig. 3). 
Cobia tagged in South Carolina were also recaptured off 
the east coast of Florida (north of Brevard/Brevard), 
primarily during November-April (zz=12). In total, 98% of 
cobia tagged in South Carolina were recaptured there or 
in the north of Brevard/Brevard zones. One cobia tagged 
within Port Royal Sound was recaptured in the GOM off 
the central coast of Florida after 2 years at large. 
