226 
Fishery Bulletin 112(2-3) 
Figure 3 
Length-frequency distributions for male (black bars) and female (white bars) Hick- 
ory Shad ( Alosa mediocris) collected from the Albemarle Sound-Roanoke River 
watershed in North Carolina during the spawning run in the spring of 1996. Fre- 
quencies are expressed as percentages, and fork lengths are delineated in 10-mm 
increments. 
ic weight and between mesentery fat and gonad weight 
were estimated by regression analyses. 
Males: log e BWT = 3.09(log e FL) - 11.76; and 
Females: log e BWT = 2.94(log e FL) - 10.80. 
(3) 
(4) 
Results 
Sex ratios, lengths, and age 
The male-to-female ratio of 0.73:l(n=266) for Albemar- 
le Sound was similar (% 2 =0.064, n= 532, df=l, P>0.05) 
to the ratio for the spawning grounds on the Roanoke 
River at Weldon (0.76:1, n= 266). Although there were 
more female Hickory Shad collected in the Albemarle 
Sound than on the spawning grounds in the river, the 
sex ratios were similar at both areas; however, in the 
RRNWR, the sex ratio was significantly skewed to- 
ward males. The independent gillnet survey conducted 
in the RRNWR was biased by the gear characteristics 
used (e.g., mesh sizes), yielding a male-to-female ra- 
tio of 4.29:1 (n = lll) — a value significantly different 
from that of the other 2 sites (x 2 =54.28, n=643, df=2, 
PcO.OOl). The mean size and range of lengths were 
larger for females than for males. Females were 280- 
402 mm FL, and males were 257-376 mm FL. Domi- 
nant size classes (10-mm increments) were 330-339 
and 340-349 mm FL for females (41.5%) and 280-289 
and 290-299 mm FL for males (47.3%) (Fig. 3). 
Body weight, or Log e body weight (BWT) measured 
in grams, increased with length, or Log e FL measured 
in millimeters, for both males (coefficient of determi- 
nation [r 2 ] =0.78) and females (7 -2 =0.73). The following 
equations were used to calculate these relationships: 
Because gonad weight varied considerably for both 
sexes, the length-weight relationship was calculated 
for somatic weight (log e SWT), improving the linear fit. 
for males (r 2 =0.81) and females (r 2 =0.76). The following 
equations were used to determine these relationships: 
Males: log e SWT = 3.01(log e FL) - 11.34; and (5) 
Females: log e SWT = 2.78(log e FL) - 9.98. (6) 
As expected, the relationship between FL and TL was 
highly correlated (r 2 =0.99). The following equation was 
used to establish this relationship: 
Log e TL = 0.99(log e FL) + 0.19. (7) 
Ages determined from scales and otoliths showed 
only a 57% agreement (n=478 pairs). On the basis of 
results of similar otolith-scale comparisons reported 
for Hickory Shad (Murauskas, 2006) and for other spe- 
cies (e.g., Kornegay, 1977; Paramore, 1998; Paramore 
and Rulifson, 2001), we assumed that otolith ages 
were accurate. With that assumption, scales generally 
overestimated the age of younger fish and underesti- 
mated the age of older fish (Table 1). However, scale 
and otolith ages never differed by more than 2 years 
for any given fish. There was no agreement between 
age-2 scales and otoliths. Agreement of age-3 scales 
and otoliths was 62%, age-4 scales and otoliths had a 
61% agreement, and only 26% of scales age 5 and older 
agreed (Table 1). 
