Vol. 53 - Alaska Resources Library and Information Services

examining their vertical larval distribution, a brief examination of
vertical distribution of these larvae in the 1980 and 1981 MOCNESS
stations suggest that they too were concentrated in the upper 40 m of
the water column.
Thus, 40 m can be considered a reasonable lower depth
limit in calculating density of these taxa in the water column.
Summary
1) The majority of Oregoniinae and Pinnotheridae occurred in the upper
40 m of the water column sampled by the MOCNESS year in 1980, 1981.
2) Although analyses of the larval vertical distribution of the other
Brachyura taxa was not possible, that data too (1980 and 1981
MOCNESS) suggest that the majority of these larvae appeared in the
upper 40 m.
5.3.2 Temporal and Horizontal Patterns of Larval Distribution
and Density
Temporal patterns of larval distribution of the non-Chionoecetes
Brachyura during the years 1976-1981 were examined to determine when
these larvae were present in the plankton of the southeastern Bering Sea
(Fig. 5.3).
Criteria were established to assure a conservative approach
to examination of the duration of larval stages (molt-frequency). These
criteria were:
1) n >= 6, where n is the number of larvae of an individual
taxon observed in a sample, and 2) at least three samples were
used to calculate the mean percent of each larval stage during each oneweek
interval.
Consequently, only one taxon, Oregoniinae, was examined
for molt-freqency patterns and only in the year 1981 because all other
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