29.12.2013 Views

Vol. 53 - Alaska Resources Library and Information Services

Vol. 53 - Alaska Resources Library and Information Services

Vol. 53 - Alaska Resources Library and Information Services

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

per female. Larvae hatch around the Pribilof Isl<strong>and</strong>s about mid-April<br />

based on limited data of Armstrong et al. (1981), <strong>and</strong> development rates<br />

may be similar to those of red king crab larvae. By June most larvae<br />

are third <strong>and</strong> fourth stage zoeae, <strong>and</strong> in July 1981 Armstrong (unpublished<br />

data) caught only megalops larvae off St. George Isl<strong>and</strong>. This<br />

implies that metamorphosis to benthic juvenile could occur in early to<br />

mid-August.<br />

An intriguing question concerning reproduction of blue king crab is<br />

whether egg development may require more than one year thus putting individual<br />

reproductive effort on a biennial schedule. Sasakawa (1973,<br />

1975) suggested that a high incidence of sexually mature, barren female<br />

blue king crab in the western Bering Sea was evidence of a 2-year cycle;<br />

19 months to incubate eggs <strong>and</strong> 5 months barren. Somerton <strong>and</strong> MacIntosh<br />

(1982) disputed this hypothesis based on their study of female crabs in<br />

Olga Bay, Kodiak Isl<strong>and</strong>. They observed males grasping ovigerous females<br />

(prelude to copulation) as the mature egg masses were hatching, <strong>and</strong> from<br />

histological evidence of ovarian maturation they concluded that individual<br />

females may reproduce in sequential years. However, a high percentage<br />

of mature females within the Olga Bay population were barren throughout<br />

the year (38%-52%), dramatizing a greatly reduced reproductive<br />

potential compared to red king crab. If such impairment of population<br />

fecundity exists about the Pribilof Isl<strong>and</strong>s, then oil catastrophes could<br />

greatly exacerbate reproductive success in a year of low mature female<br />

abundance <strong>and</strong> a high incidence of barren animals<br />

551

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!