778 
Fishery Bulletin 95(4), 1997 
Growth 
Mean growth rates (mean SL divided by mean age) 
varied from 0.18 mm/d in the MAB to 0.41 mm/d in 
Chesapeake Bay (Table 1). Furthermore, early- 
spawned fish experienced considerably faster growth 
than late-spawned fish (Table 1). 
Early-captured larvae grew 37% faster than late- 
captured larvae for individuals <15 mm SL and <80 d 
(Fig. 4A). Early-captured individuals were larger at 
age than late-captured individuals because of differ- 
ent growth rates and not because of larger size at 
hatching, as indicated by tests of regression coeffi- 
cients that showed highly significant differences be- 
tween slopes (P<0.001) but not between intercepts 
(P=0.16). 
Early-spawned larvae grew 39% faster than late- 
spawned larvae (Fig. 4B), and once these size differ- 
ences were established, they persisted through the 
juvenile stage (Fig. 40. There was a significant dif- 
ference between slopes (PcO.OOl) for early- and late- 
spawned larvae, whereas, early- and late-spawned 
juveniles experienced similar growth according to 
tests of regression coefficients (P=0.75). Furthermore, 
Tabie 1 
Mean standard length (mm) and standard error (SE), age (d) (SE), and growth rate (mean SL/mean age) for larval and juvenile 
Atlantic croaker collected in the Middle Atlantic Bight and estuarine waters of Virginia from 21 September 1987 to 10 March 
1988 by hatching month, region, and gear type. 
Hatching 
month 
Sample 
size 
Mean standard 
length ± SE 
Mean age 
± SE 
Mean growth 
Middle Atlantic Bight (MAB) i 
Sep 
19 
7.9 ±0.2 
43.7 ± 0.9 
0.18 
Oct 
21 
5.8 ± 0.4 
29.7 ± 1.5 
0.20 
Seaside Eastern Shore (SES: Wachapregue and Sand Shoal Channel) 2 
Aug 
17 
13.2 ± 1.5 
41.0 ± 3.8 
0.32 
Sep 
115 
11.0 ±0.5 
42.7 ± 1.8 
0.26 
Oct 
6 
13.6 ± 0.8 
56.5 ± 1.1 
0.24 
Bayside Eastern Shore (BES: Occohannock Channel) 2 
Aug 
1 
28.3 ± 0.0 
94.0 ± 0.0 
0.30 
Sep 
32 
14.4 ± 0.7 
67.1 ± 1.2 
0.21 
Oct 
15 
11.0 ± 0.2 
57.5 ± 0.7 
0.19 
Chesapeake Bay 3 
Jul 
7 
25.8 ± 6.5 
77.3 ± 11.2 
0.33 
Aug 
74 
28.9 ±2.0 
70.5 ± 3.8 
0.41 
Sep 
21 
27.8 ± 3.4 
78.4 ± 8.0 
0.36 
Oct 
21 
35.4 ± 1.7 
94.2 ± 2.7 
0.38 
Nov 
7 
20.4 ± 1.3 
71.6 ± 1.0 
0.29 
Marshes (Guinea and Tue Marshes) 2 
Jul 
10 
24.0 ± 2.4 
71.2 ±3.0 
0.38 
Aug 
39 
16.5 ± 1.2 
48.6 ± 2.2 
0.34 
Sep 
75 
9.8 ±0.3 
47.0 ± 2.2 
0.21 
Oct 
4 
10.6 ±0.6 
60.0 ± 1.0 
0.18 
Jan 
7 
12.7 ±0.4 
54.7 ± 2.0 
0.23 
Rivers (York and James River) 3 
Sep 
13 
48.5 ± 2.2 
124.3 ± 1.7 
0.39 
Oct 
25 
32.1 ± 2.1 
105.3 ± 2.2 
0.30 
Nov 
28 
27.6 ± 2.0 
91.5 ± 2.8 
0.30 
Dec 
32 
31.8 ±2.2 
89.5 ± 2.9 
0.36 
Jan 
15 
24.4 ± 1.7 
74.4 ± 1.4 
0.33 
Feb 
1 
10.6 ± 0.0 
49.0 ± 0.0 
0.22 
1 Gear type used was oblique 60-cm bongo nets with 505-gm mesh. 
2 Gear type used was a 4.9-m lined trawl net with a 6.4-mm mesh and 3.2-mm mesh liner and a 4.9-m unlined net with a 15.9-mm mesh. The lined 
and unlined nets were towed simultaneously. 
3 Gear type used was a 9.1-m lined trawl net with a 15.9-mm mesh and 6.4-mm mesh liner. 
