Vol. 53 - Alaska Resources Library and Information Services

Dendrograms and two-way tables (not illustrated) were generated by
multivariate methods (EAP 1982). Similarity analysis of biomass data
from trynet samples resulted in the identification of two major sample
groups. The distribution of samples in these two groups is displayed in
Figure 3.7-1. The two groups, an offshore and nearshore group, overlap
between the 50 and 70 m isobaths along the Alaska Peninsula and along
the 50 m isobath in the northeast portion of the study area. The
average depth of the 43 samples in the offshore group was about 62 m;
the 99 samples in the nearshore group averaged about 36 m depth.
Similarity analysis resulting in species groups exhibited a great degree
of species overlap between sample groups, indicating widespread distributions
for many of the species taken in trynet samples. A group of
three species occurred at their maximum biomass in the offshore samples:
the red king crab, the ascidian Boltenia ovifera ; and the Tanner crab
(Chionoecetes bairdi). The king crabs in these offshore samples were
primarily adults and older juveniles. The species characteristic of
nearshore trynet samples included: yellowfin sole (Limanda aspera); rock
sole (Lepidopsetta bilineata); sea star (Asterias amurensis); hermit
crab (Pagurus ochotensis); Pacific cod (Gadus macrocephalus); and
pollock (Theragra chalcogramma). These species were also present in
offshore samples, but at lower biomass values.
Two major sample groups were also identified from similarity analysis
of rock dredge biomass data; their distributions are shown in Figure
3.7-2. Samples in group AB had a more widespread distribution than
those in group CD, which was found along shore and in shallow areas.
The 33 group AB samples had an average depth of approximately 37 m; the
34 group CD samples averaged about 23 m depth.
The four species groups identified from the rock dredge data formed two
major groups. The species characteristic of sample group AB were
essentially those described for the trynet nearshore group. Rock dredge
hauls in sample group CD were generally devoid of the major species of
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