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Fishery Bulletin 112(2-3) 
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03 
n 
o 
TL (mm) 
B 
q 0.8 
TL (mm) 
TL (mm) 
Figure 4 
TL (mm) 
Predicted probabilities of tag returns in each recapture area as a function of total length (TL) and annual total stock abun- 
dance (millions of fish) of Striped Bass (Morone saxatilis ) during the period of 1991-2008. We used the following 4 recapture 
areas (A) Albemarle Sound estuary, (B) Pamlico Sound estuary, (C) North Carolina ocean waters, and (D) northern coastal 
waters (for locations, see the map in Fig. 2B). Probabilities are based on parameter estimates from the most parsimonious 
multinomial logistic regression model that related the recapture area of Striped Bass to TL and stock abundance. Cooler 
and warmer colors represent low and high tag return probabilities, respectively, as follows: (0.0, H; 0.2, H; 0.4, 9; 0.6, D; 
0.8, H; 1.0, ■). Note that tag return probabilities sum to 1.0 (across recapture areas) for a given combination of TL and 
stock abundance. 
vest), the lack of ocean recaptures by Hassler et al. 1 
is not surprising. Nearly all fish recaptured in their 
study (>99%) were smaller than the size at which ap- 
preciable ocean emigration occurs (>800 mm TL), as 
indicated in our study. 
Although other factors, such as prey availability 
and susceptibility to predation, may be involved, wa- 
ter temperature appears to be a salient factor in ex- 
planation of the size-dependent migration and distri- 
bution patterns of the AR stock. A change in tempera- 
ture preferences with fish size has been hypothesized 
to be the main driver of the size-dependent emigration 
pattern observed previously for other stocks of Striped 
Bass (Coutant, 1985), especially the Chesapeake stock 
(Dorazio et al., 1994; Secor and Piccoli, 2007). 
Decreases in temperature optima with fish size can 
be explained by bioenergetic principles. Specifically, the 
temperature threshold beyond which the increase in to- 
tal metabolic load starts to become stressful (i.e. , the 
point at which the scope for activity and growth begins 
