Vol. 53 - Alaska Resources Library and Information Services

7.1.2 Reproduction
Reproductive season among hermit crabs differs by species and locality
(Nyblade 1974).
Copulation and egg extrusion usually occur from autumn
through spring.
Some species have a single brood and release larvae
only in the spring, while multiple brooders may release larvae throughout
the summer months (Table 7.2).
Egg development time from extrusion to
hatching has been recorded only for the second brood in multiple brooding
species, and varies from 1.5 to 2.0 months in the laboratory (Nyblade
1974). Egg size and number per female also vary with species. Like the
larvae of other invertebrates, those of hermit crabs appear in the water
column later in more northern waters (Stephenson 1935; Pike and Willliamson
1959).
Therefore, with some allowance for latitude, the laboratory
and field data of Nyblade (1974) for hermit crabs collected in the San
Juan Archipelago (Table 7.2), may be applied tentatively to the same species
found in the southeastern Bering Sea.
Zoeal duration for most species
falls in the range of 50-60 days.
Laboratory studies have demonstrated
that they are primary carnivores during this period and may feed
on copepod nauplii, copepodites, barnacle nauplii, polychaete trochophores,
and other small planktonic larvae (Roberts 1974).
Duration of
the megalops stage is approximately 21 days with little variation among
species.
7.1.3 Benthic Distribution
Individual species of adult and juvenile hermit crabs were found in
as many as 46% of benthic trawls taken in the southeastern Bering Sea in
1975 (primarily north of the Pribilof Islands and shallower than 80 m)
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