Reese et at: Distribution and estuarine interactions between wild and hatchery Oncorhynchus keta 
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Inner Inlet 2004 
O 
Inner Inlet 2005 
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Outer Inlet 2004 
A- 
Outer Inlet 2005 
Figure 4 
Weekly proportions of wild chum salmon (Oncorhynchus keta) fry from beach 
seine and Kodiak trawl sets in (A) littoral, and (B) neritic habitats of inner 
and outer Taku Inlet, Alaska, by week during the outmigration period for wild 
fry (late April to mid- June). No chum salmon were caught in neritic habitat 
before 10 May in 2004 and 2005. Early hatchery chum salmon were released 
near the inlet on 10 May and 17 May 2004 and 9-12 May 2005. Late hatchery 
fry were released 22-26 May 2004 and 22 May to 3 June 2005. 
(Fig. 3). The proportion of wild fry was greatest in 
the inner inlet (Fig. 4), but abundance of both wild 
and hatchery chum salmon was greatest in the outer 
inlet. 
Spatial and temporal change in body size 
of hatchery and wild salmon 
Littoral habitat Early and late hatchery fry both were 
on average about four times heavier and about 15 mm 
FL longer than wild fry in littoral habitat (Fig. 5). Early 
hatchery fry were similar in size to late hatchery fry by 
the time the latter were released (Fig. 6). For wild fry in 
the inner inlet, mean weight and length were 0.39 g and 
36.5 mm FL in 2004 and did not increase throughout the 
season (Fig. 6; regression probability that slope of size 
over time=0, P=0.62). In 2005, weight and length of wild 
fry did increase significantly (P=0.03), but the increases 
were relatively small, from 0.38 to 0.48 g and from 37 
to 42 mm FL (Fig. 6). In the outer inlet, by contrast, 
wild fry more than doubled in weight and mean length 
increased significantly (P<0.01) through the season in 
both years, from 37 to 50 mm FL (Fig. 6). For early 
hatchery fry, mean length in the inner inlet increased 
significantly (P=0.02) over time from 51 to 54 mm FL 
in 2004, but did not change in 2005 (P=0.94). In the 
outer inlet, mean weight of early hatchery fry increased 
significantly (P<0.01) by 80% in both years and mean 
length increased significantly (P<0.01) from 52 to 60 
mm FL in 2004 and from 53 to 63 mm FL in 2005 (Fig. 
6). For late hatchery fry, mean length in littoral habitat 
in the outer inlet did not change significantly in either 
2004 (P=0.24) or 2005 (P=0.08). 
Neritic habitat Hatchery chum salmon fry in neritic 
habitat were longer than wild fish in the inner and outer 
