Publication Date:
2015-01-14
Description:
Snow crabs Chionoecetes opilio are quite productive at suitable temperatures, but
can also be abundant in water cold enough to depress settlement of larvae, growth, and reproduction.
In much of the northern Bering Sea, bottom water temperatures are below −1°C for most or
all of the year. Crab pelagic larvae prefer to settle at temperatures above 0°C, so we found high
densities of juveniles only where intruding warm currents deposited larvae in localized areas.
After settlement, maturing crabs appeared to exhibit ontogenetic migration toward deeper,
warmer water. Cold temperatures excluded key predators, but decreased fecundity by restricting
females to small body size (with associated small clutches) and to breeding every 2 yr. Migration
to warmer water may allow females to breed annually and to encounter more adult males needed
to fertilize subsequent clutches. Because older males also emigrate, remaining adolescent males
probably inseminate newly maturing females. Without localized intrusion of warmer currents,
snow crabs might not persist at high densities in such cold waters. However, they are currently
very abundant, and export many pelagic larvae and adults.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
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