30 
Fishery Bulletin 1 12(1) 
Table 5 
Summary of recapture information for Cobia (Rachycentron canadum) released in South Carolina 
with external tags. Distance values represent the distance from the specific stocking location in Port 
Royal Sound to the recapture location. Calibogue Sound is a small estuary in the vicinity of Port 
Royal Sound and St. Helena Sound estuaries in South Carolina (SC). 
Year 
class 
Tag no. 
Release 
date 
Recapture 
date 
Recapture 
location 
Days at 
large 
Distance 
(km) 
2004 
M0562 
05/11/05 
05/27/05 
Port Royal Sound 
16 
2004 
M1472 
05/11/05 
05/28/05 
Port Royal Sound 
17 
10.0 
2004 
M1382 
05/11/05 
06/09/05 
Port Royal Sound 
29 
10.0 
2004 
M1397 
05/11/05 
06/09/05 
Port Royal Sound 
29 
10.0 
2004 
M1434 
05/11/05 
06/12/05 
Port Royal Sound 
32 
- 
2004 
M1477 
05/11/05 
08/25/05 
Port Royal Sound 
106 
11.6 
2004 
M1326 
05/11/05 
05/16/06 
Port Royal Sound 
370 
- 
2005 
M2079 
05/03/06 
05/07/06 
Port Royal Sound 
4 
0.0 
2005 
M2245 
04/27/06 
05/02/06 
Port Royal Sound 
5 
12.2 
2005 
M2082 
05/03/06 
05/10/06 
Port Royal Sound 
7 
11.0 
2005 
M2357 
05/03/06 
05/10/06 
Port Royal Sound 
7 
11.0 
2005 
M2360 
05/03/06 
05/10/06 
Port Royal Sound 
7 
10.0 
2005 
M2327 
05/08/06 
05/16/06 
Port Royal Sound 
8 
10.0 
2005 
M2282 
04/27/06 
05/06/06 
Port Royal Sound 
9 
10.0 
2005 
M2081 
05/03/06 
05/12/06 
Port Royal Sound 
9 
9.3 
2005 
M2227 
05/03/06 
05/12/06 
Port Royal Sound 
9 
12.2 
2005 
M2310 
05/08/06 
05/17/06 
- 
9 
- 
2005 
M2089 
05/03/06 
05/13/06 
Port Royal Sound 
10 
11.0 
2005 
M2234 
04/27/06 
05/08/06 
Port Royal Sound 
11 
11.0 
2005 
M2239 
04/27/06 
05/08/06 
- 
11 
- 
2005 
M2321 
05/08/06 
05/20/06 
Port Royal Sound 
12 
10.0 
2005 
M2018 
04/27/06 
05/10/06 
Port Royal Sound 
13 
0.0 
2005 
M2091 
05/03/06 
05/17/06 
Port Royal Sound 
14 
11.0 
2005 
M2132 
05/03/06 
05/17/06 
Port Royal Sound 
14 
- 
2005 
M2 155 
05/03/06 
05/17/06 
Port Royal Sound 
14 
11.0 
2005 
M2205 
05/03/06 
05/17/06 
Port Royal Sound 
14 
10.0 
2005 
M2285 
05/08/06 
05/22/06 
Port Royal Sound 
14 
11.0 
2005 
M2024 
04/27/06 
05/12/06 
Port Royal Sound 
15 
10.0 
2005 
M2210 
05/03/06 
05/19/06 
Port Royal Sound 
16 
11.0 
outside of the stocked area (3 in SC and 2 in Florida); 
however, these fish were recaptured either outside of 
the spawning season (September-October) or just be- 
fore or at the onset of the spawning season (early May). 
Although the sample sizes for recaptures at large for at 
least one year were small (n = 13), all of the recaptures 
during the spawning season (n= 8) occurred within the 
inshore vicinity of the stocked estuary. 
Population structure 
On the basis of the 2008 samples, pairwise compari- 
sons of both genotypic distributions and hierarchical 
f?ST values indicated no differences among the off- 
shore collection locations (G-test: P= 0.075, /?st= 0 005, 
P=0.14; Table 6). However, the two inshore collec- 
tion locations were significantly different from both 
each other (G-test: P<0.001; PgT : 0.043, P<0.001) 
and from the homogenous offshore group (G-test: 
P<0.001; Rst- 0.011-0.023, P<0.05); with the excep- 
tion of the inshore VA and offshore NC collection lo- 
cations. The AMOVA results were consistent with 
this pattern, showing significant differences among 
populations (1.6%, P<0.001, Table 7) and the highest 
proportion of among-group molecular variation (1.3%) 
when grouped according to the pair-wise results. Re- 
sults derived from the 2009 samples were concor- 
dant with the patterns detected in 2008 (AMOVA: 
1.2%, P<0.001; 2.3% among groups), with the SC in- 
shore collection being significantly different (G-test: 
PcO.001; PsT ; 0.017-0.018, P<0.009) from the ho- 
mogenous NC and SC offshore group (G-test: P= 0.53; 
Pst=0-006, P=0.16; Table 8). Results from use of the 
Structure software for both collection years supported 
the pairwise and AMOVA patterns of genetic differen- 
tiation (Fig. 2). On the basis of trajectories of both Ln 
probabilities and variance metrics, k (number of popu- 
lations) was estimated at 3 populations for the 2008 
