Moiseev et al: Effects of pot fishing on the physical condition of Chionoecetes opilio and Chionoecetes bairdi 
245 
Table 3 
Copper concentration, [Cu], measured in micrograms (g wet weight -1 ), in samples of the hepatopancreas of snow crab (Chi- 
onoecetes opilio) and southern Tanner crab (C. bairdi ) under different experimental conditions. [Cu] values are means (±1 
standard error [SE] ). 
C. bairdi 1 
C. opilio 2 
Experimental conditions 
[Cul No. of samples 
[Cu] No. of samples 
Immediately after capture 
Starvation in a crab pot within a period of 55 days 
Repeated pot hauls at short time intervals (<3 days) 
5.5(1.3) 7 
37.3 (18.5)* 5 
17.0(12.1) 6 
0.92(0.07) 7 
2.6 0.8) 6 
1 19 September-12 November 2008, 6-11 October 2008, Sea of Okhtosk (area I). 
2 17 October-3 November 2008, Sea of Okhtosk (area II). 
* Significantly different from that of individuals sampled immediately after capture (P<0.05), Student’s t-test. 
cess nutrients as circulating oligomeric proteins seems 
a bit expensive” (p. 1088). Nonetheless, studies have 
shown that concentrations of total protein and He in 
hemolymph steadily decrease in starved animals under 
laboratory conditions (Hagerman, 1983; and references 
therein). However, it is probable that some of these 
effects were a result not of reduction in the absolute 
amount of protein but of dilution of the protein. Dali 
(1974) showed that blood protein concentration in the 
longlegged spiny lobster ( Panulirus longipes ) decreased 
with starvation within 4 weeks, but this decrease was 
actually due to the increase in blood volume as solid tis- 
sues were metabolized. Djangmah (1970) observed that 
blood protein decreased from 7.9 g L _1 to 2.55 g L _1 and 
that there was a progressive accumulation of copper 
in the hepatopancreas of the common shrimp ( Crangon 
crangoti ) after 23 days of starvation. He suggested that 
the stored copper came from catabolism of He, which 
is, therefore, rendered usable as an energy source in a 
starving animal. Laboratory studies showed that the 
changes of [He] elicited by food availability occurred 
gradually over periods of many days (Djangmah, 1970; 
Hagerman, 1983). However, Spicer and Stromberg 
(2002) demonstrated that starvation had a significant 
effect on [He] in northern krill ( Meganyctiphanes nor- 
vegica ) over the course of a few hours (<10) under labo- 
ratory conditions. They used laboratory studies to in- 
terpret changes in krill [He] that they observed during 
the diel vertical migration of northern krill. Spicer and 
Stromberg (2002) attributed such dramatic decreases 
in [He] in starved individuals to the high metabolic 
rates of northern krill. 
During our experiments, crabs were not fed because 
it was not possible to control the amount of food con- 
sumed by individuals. Any food placed in crab pots is 
quickly eaten by predatory amphipods, which also are 
thought to attack weak or injured crabs (Ivanov and 
Karpinski, 2003). Because the duration of our experi- 
ments was up to several weeks, there was a need to 
determine to what extent the fall in crab [He] was re- 
lated to the forced starvation of animals during the 
experiments. In our experiments on the effects of star- 
vation on crabs, at pot soaking durations of 14, 16, 
and 25 days, [He] in snow crab and southern Tanner 
crab did not change significantly compared with [He] 
in crabs immediately after capture (Fig. 6A). A signifi- 
cant drop in mean [He] between crabs before and crabs 
after soaking was observed only in experiment 9, in 
which crabs soaked in a pot for 55 days (Fig. 6, B and 
C). We, therefore, assume that starvation had no sig- 
nificant effect on the changes in the [He] in crabs in 
all experiments that involved repeated pot hauls be- 
cause, in these experiments, [He] significantly changed 
over the course of a few days. 
A rapid decrease in [He] in crustaceans may be as- 
sociated with the processes of anaerobic metabolism, 
which is one of the major physiological responses to O2 
deprivation. Increases of lactate and bicarbonate-carbon- 
ic acid during anaerobic metabolism result in increased 
hydrogen ion concentration and a drop in pH in crusta- 
cean hemolymph (Barrento et al., 2009; and references 
therein). Crustaceans have compensation mechanisms 
that act in response to acidosis through mobilization 
of buffer bases. However, during severe and prolonged 
hypoxia, the ability of an organism to compensate may 
be exhausted. When no further metabolic compensa- 
tion occurs, the pH level will drop below the tolerated 
range and, as a result, the rates of enzymatic reactions, 
ionic and osmoregulatory controls, and cell membrane 
structure will be affected. Poor health, morbidity, and 
mortality have been reported to be correlated with low 
pH values in crustaceans (Whiteley and Taylor, 1992; 
Ridgway et al., 2006). 
In laboratory experiments, Norway lobster ( Neplirops 
norvegicus) exposed to water with low concentration of 
dissolved O2 (<20% 02-saturation) showed a sudden and 
rapid decrease in [He] (Baden et al., 1990). The length 
of time before the decline began depended on the O2 
concentration. When lobster were exposed to 10% 02- 
saturation, an immediate reduction of their mean [He] 
