Vol. 53 - Alaska Resources Library and Information Services

the benthic habitat associated with the islands (e.g., predator refuge),
and/or restriction by virtue of some sort of competitive, agonistic
interaction with other species.
Confinement of the species to a small
area about St. Paul Island makes them extremely vulnerable to oil
catastrophes originating in the northern St. George Basin lease sale
area (Fig. 3.8).
On a broader scale, blue king crab tend to be more northerly in
distribution than red king on both sides of the Pacific. Slizkin (1973)
found high abundance of adults off Cape Navarin and reported juveniles
even farther north to Cape Cukotsky (64°N latitude).
He concluded that
blue king crab are more tolerant of colder temperatures (1-2°C) than are
red king crab, and that this differential partially explains species
separation.
The depth range of main aggregations of blue king crab is about
45-75 m on a mud-sand bottom, although gravel to rocky substrate is
found immediately adjacent to both Pribilof Islands. Otto et al. (1982)
note that estimates of female and juvenile blue king crab around both
the Pribilof and St. Matthews islands are low because of some distribution
over rocky, untrawlable bottom. These observations strongly
suggest that spawning and successful recruitment of first instar juveniles
may depend on availability of nearshore, rocky-cobble substrate
for protection of both females and small juveniles.
Later, as older and
larger animals, populations disperse farther offshore although still in
a small area on the scale of the southeastern Bering Sea.
Dependence of
early benthic juveniles on refuge substrate is substantiated by
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