136 
Fishery Bulletin 112(2-3) 
Figure 3 
Time series for the period of 1991-2008 of the following trends of the Albemarle 
Sound-Roanoke River stock of Striped Bass ( Morone saxatilis ): 1) total annual 
abundance (millions of fish; gray bars) of the stock (age 1+ fish) estimated from 
a statistical catch-at-age model (NCDMF and NCWRC 2 ), 2) annual percentage of 
tag returns (solid line) that occurred outside the Albemarle Sound estuary from 
Striped Bass tagged and released on the spawning grounds in the upper Roanoke 
River, and 3) catch per unit of effort for fish (number h -1 ) age 9+ (>700 mm in total 
length) (dashed line) in annual spring electrofishing surveys on the Roanoke River 
spawning grounds. 
population rebuilt over the past 2 decades (1991-2008). 
In the early 1990s, few tag returns occurred outside 
the Albemarle Sound estuary: <4% annually across the 
years of 1991-96, with the exception of 1995 (Fig. 3). 
However, as the stock increased in abundance and its 
age structure expanded, returns from regions outside 
the Albemarle Sound estuary increased considerably 
and ranged from 15% to 31% annually during the years 
of 1997-2008 (Fig. 3). 
Effects of fish size and stock abundance on recapture area 
Fish size and stock abundance affected recapture area. 
The best multinomial logistic regression model in- 
cluded the main effects of both fish length and stock 
abundance but not their interaction (Table 2). Good- 
ness-of-fit tests indicated this model fitted the sample 
data well (Pearson goodness of fit, x 2 =H7, degrees of 
freedom=126, P=0.70; deviance goodness of fit, % 2 =104, 
degrees of freedom=126, P=0.93). Although the best 
model showed that recapture area depended on both 
fish size and stock abundance, AIC diagnostics across 
the suite of models indicated that fish length exerted 
a much stronger effect than abundance. Specifically, 
the model that included only fish length had moderate 
empirical support (A;=3.8, mi=0.12), but the model that 
included stock abundance alone had very little support 
(A i= 462.2, h^O) (Table 2). 
Striped Bass of the AR stock exhibit a strong size- 
dependent migration pattern, whereby both the inci- 
dence of emigration and the distance emigrants move 
increase with fish size. The best model predicted that 
the probability of emigration from (i.e., recapture 
outside) the Albemarle Sound estuary increased dra- 
matically with fish size. Specifically, the probability 
of recapture within Albemarle Sound declined sharp- 
ly (from values >90%) beyond 600 mm TL, the size 
at which recapture probabilities began to increase in 
other areas, such as Pamlico Sound and ocean waters 
(Fig. 4). The model predicted that Striped Bass 700- 
800 mm TL in length were most likely to be recap- 
tured in ocean waters of North Carolina (Fig. 40 and 
that the largest fish (>850 mm TL) were most likely 
to be recaptured in the northern coastal region (Fig. 
4D). 
Empirical tag return data supported the move- 
ment pattern indicated by the best model. Nearly all 
(92%) of the tag returns of smaller fish (<600 mm TL; 
