Vol. 53 - Alaska Resources Library and Information Services

The occurrence of a multi-stage larval population may, in part,
simply reflect geographic differences in hatch time. Data in Figures
3.17a and b were grouped from the entire geographic area of strata I and
II for the time intervals shown because samples were so few. However,
in 1982, stations from Amak Island to Cape Seniavin were collected in a
six-day period along this 215 km distance. By grouping zoeal stages
SI+SII and SIII+SIV, and calculating frequency of occurrence, the
resultant data suggest an earlier hatch along the western than along the
eastern NAS (Fig. 3.18). Around Amak Island, SIII+SIV larvae comprised
80 to 100% of total populations but by Cape Seniavin SIII+IV were only
32% (Fig. 3.18).
The total period of larval development is estimated to take about
4.5 months from hatch of first zoeal in early April, to metamorphosis of
megalopae in mid to late August (Fig. 3.17b). Megalopae were collected
as early as June 15 in 1978, but more typically in early July and
August, 1981 and 1982, respectively. Since 45% and 55% of larvae were
SIV and megalopae in early August, 1982 (Fig. 3.17b), metamorphosis to
the benthos probably did not occur until late August to early September
for much of that year class.
Blue King Crab: Very little data are available with which to gauge
hatch and metamorphosis of P. platypus (the OCSEAP FY83 Pribilof Island
program on blue king crab should improve this data base). The earliest
samples containing blue king crab were collected in late May, 1976, and
all larvae were SI and II. In late June, 1978, a few Pribilof Island
stations had SIV larvae, and in early July, 1982, all larvae caught were
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