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Vol. 53 - Alaska Resources Library and Information Services

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females. This relationship supports the observations of the 1982<br />

NMFS survey cruise that found an unusually large number of barren<br />

female crabs in a year of very low male abundance. The relationship<br />

between spawners <strong>and</strong> eventual recruits for this species is unclear<br />

(Reeves <strong>and</strong> Marasco 1980).<br />

Females carry eggs for up to 11 months as embryos develop through<br />

naupliar stages to prezoea (Marukawa 1933). This protracted developmental<br />

time makes eggs (during early cleavage) <strong>and</strong> later embryos<br />

susceptible to long-term benthic oil pollution, <strong>and</strong> should be considered<br />

in scenarios of oil mishaps <strong>and</strong> possible perturbations to larval populations.<br />

Again, gravid king crab females are aggregated nearshore in<br />

relatively shallow water along the North Aleutain Shelf, but such<br />

distribution is poorly studied to date.<br />

1.3.3 Larval Biology<br />

Time <strong>and</strong> Area of Hatch. Larvae are hatched nearshore (Armstrong, et al.<br />

1983b; Haynes 1974), molt through four zoeal stages, each about three<br />

weeks (Armstrong, et al. 1983b; Marukawa 1933), spend two to four weeks<br />

as megalopae, <strong>and</strong> then metamorphose to first instars about late July<br />

to August (Armstrong, et al. 1983b; Kurata 1960; Weber 1967). Eggs<br />

normally begin to hatch in early April (Haynes 1974; INPFC 1960; Sato<br />

1958), although female king crab may vary in time of hatch between<br />

widely separated populations from Unimak Isl<strong>and</strong> to Port Moller. Korolev<br />

(1968) summarized data collected by Soviet scientists for June 1959<br />

along the North Aleutian Shelf. Over 95 percent of the female populations<br />

between 161°25 ' to 165°10'W had spawned <strong>and</strong> carried new egg masses<br />

in June, while 90 percent of females east of 161°25'W (Port Moller <strong>and</strong><br />

east) carried empty egg cases indicative of recent hatch, <strong>and</strong> only 10<br />

percent carried new purple egg masses. Armstrong, et al. (1983b) have<br />

presented evidence that egg hatch is not synchronous along the NAS from<br />

Unimak Isl<strong>and</strong> to Cape Seniavin, <strong>and</strong> concluded that larvae emerge earlier<br />

in the southwest portion of the NAS range <strong>and</strong> later to the northeast,<br />

probably in accord with differences in water temperature.<br />

289

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