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Fishery Bulletin 108(2) 
Days starved 
Days starved 
Figure 3 
Average fork length (mm, top panels) and wet weight (g, bottom panels) for juvenile chum 
salmon ( Oncorhynclius keta) starved over time in the laboratory after capture in the 
marine waters of Icy Strait and Upper Chatham Strait in the northern region of south- 
eastern Alaska, during June (left panels) and July (right panels) 2003. Error bars are 
one standard error about the mean. Significant differences (Tukey’s paired comparisons; 
P<0.05) and percent change between sample intervals are shown in inset boxes. 
juvenile chum salmon during starvation. Limited infor- 
mation has been published on the changes in condition of 
laboratory-reared chum salmon due to starvation. Such 
studies typically show depletion of stored nutrients and 
declines in condition and size over time, despite differ- 
ences in methods (LeBrasseur, 1969; Akiyama and Nose, 
1980; Murai et ah, 1983; Ban et al., 1996). For nutrient 
responses, lipid and serum protein levels of laboratory- 
reared juvenile chum salmon were lowest after 10 and 
20 days of starvation, respectively (Ban et ah, 1996); 
unfortunately, however, energy content was not deter- 
mined. We did not directly measure lipid and protein, 
but the decline in WBEC that we observed between days 
zero and 10 and between days 20 and 45 in June could 
reflect similar declines in these nutrient measures. For 
condition responses, two studies showed that %MC of 
small starved juvenile chum salmon increased by 4.3% 
(41 mm and 0.45 g initial size; 42-d starvation; LeBras- 
seur, 1969) to 5.4% (0.26 g initial size; 28-d starvation; 
Murai et ah, 1983) at ~15°C; another study showed that 
% MC of larger starved juvenile chum salmon increased 
by 12% (94.5 mm and 7.9 g initial size; 91-d starvation; 
Akiyama and Nose, 1980) at 17°C. Trends in %MC of 
our juvenile chum salmon were comparable despite the 
differences in fish size, duration of starvation, and water 
temperature. For size responses, weight decreased for 
five size-groups of juvenile chum salmon (0.46-7.95 g 
initial size; 5-13 wk starvation); however, the percentage 
weight loss decreased as fish size increased (Akiyama 
and Nose, 1980). These differences in weight loss among 
fish sizes indicate that physiological responses to starva- 
tion may vary with ontogeny. 
Our results are also comparable to information avail- 
able for other salmonid species and stages. For starved 
juvenile sockeye salmon (O. nerka), energy density de- 
clined more rapidly and %MC increased more rapidly 
with increasing temperatures (Brett et ah, 1969). In our 
study, chum salmon in June exhibited a 40% decline in 
WBEC and a 9% increase in %MC after 45 days of star- 
vation at an average temperature of ~9°C. By compari- 
son, at similar temperatures (10°C), laboratory-reared 
juvenile sockeye salmon lost 37% of initial WBEC and 
gained 9% MC during 99 days of starvation (Table 3 in 
Brett et al., 1969). Such inverse relationships between 
fraction water and fraction lipid or energy content are 
often reported during starvation (Miglavs and Jobling, 
1989; Simpkins et al., 2004; Breck, 2008). In a few 
studies, size changes similar to those that we observed 
have also been reported among other starved salmo- 
nids. Weight decreased for starved juvenile Arctic charr 
