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Vol. 53 - Alaska Resources Library and Information Services

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The results of correlation analysis indicated that several physical <strong>and</strong><br />

biological factors were related to the density distribution of red<br />

king crabs. Tables 3.5-3, 3.5-4 <strong>and</strong> 3.5-5 present the correlation<br />

matrices for cruises 83-1, 83-3 <strong>and</strong> 83-5, respectively. Generally, king<br />

crab density for age groups young-of-the-year through age 2 was negatively<br />

correlated with depth, whereas the density of crabs age 2+ <strong>and</strong><br />

older was positively correlated with depth. Young-of-the-year crab<br />

density was positively correlated with gravel presence in sediments<br />

<strong>and</strong> with bottom water temperature. None of these correlations was<br />

statistically significant.<br />

Variables related to the density distribution of 0+ or young-of-the-year<br />

crabs were bryozoan biomass during the April-May cruise (r=0.5280),<br />

sea urchin biomass during the June <strong>and</strong> September cruises (r=0.7011;<br />

r=0.5746, respectively), <strong>and</strong> polychaetes <strong>and</strong> gravel during the September<br />

cruise (r=0.8607, r=0.6090, respectively). Densities of age 1, 1+ <strong>and</strong> 2<br />

crabs were significantly correlated with sea urchins (r=0.7239) during<br />

the April-May cruise, <strong>and</strong> with polychaetes <strong>and</strong> salinity (r=0.5225,<br />

r=0.6404, respectively), during the September cruise. Densities of<br />

crabs age 2+ <strong>and</strong> 3 were correlated with the sea onion (r=0.6965)<br />

during the April-May cruise, <strong>and</strong> with age 3+ <strong>and</strong> older red king crabs<br />

(r=0.5975) during the June cruise.<br />

The results of multiple linear regression analysis are presented in<br />

Appendix E. For age class 0+, the sea star (Asterias amurensis) biomass<br />

was the most important variable for data from the April-May cruise,<br />

while sea urchin (Strongylocentrotus droehbachiensis) biomass was the<br />

most important variable in June. During September, three variables each<br />

accounted for 74 percent or more of the variability in YOY crabs for the<br />

single variable model; these were: polychaete biomass (r²=0.7418);<br />

salinity (r 2 =0.8211); <strong>and</strong> sea urchin biomass (r 2 =0.9982).<br />

Sea urchin biomass was also important in the regression models using<br />

data for age 1 through 2 crabs, accounting for 95 percent of the vari-<br />

363

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