Vol. 53 - Alaska Resources Library and Information Services

most probably due to the mix of species in our samples.
Even though
they have 5-7 larval stages before the megalops is reached, the majority
of larvae (given a 2 week intermolt period) would have metamorphosed and
settled out of the water column by early August in 1981.
In April of
that year, 93% of the larvae were SI in April, while 58% were megalopae
by July.
Argis spp. (A. lar, A. dentata and A. ovifer) were present at 2% or
13 of the 626 station locations sampled from 1976-1981 (Fig. 6.26).
Except for one station (A 5 on the PROBES A line), they favored the
mid-shelf domain and stations < 100 m sonic depths. All stages, I, II
and megalopae, were taken during April to July. Megalopae in particular
were taken as early as May 23rd (NOAA, R/V Alaska) and as late as July
4th (PROBES) in 1981.
Distribution and Abundance:
Four species of adult crangonids, Crangon
communis, C. dalli, Argis dentata, and A. lar, are routinely taken
during trawl surveys of the St. George Basin (Paul Anderson, NMFS,
Kodiak, Alaska, personal communication). According to Ivanov (1969),
crangonid adults dominate the 0-50 m depth zone of the inner shelf
domain. This region was only sporadically sampled during the 1976-1981
cruises and thus substantiation of this fact was difficult.
However,
nearshore distribution of crangonids was confirmed during the 1982
OCSEAP cruises along the North Aleutian Shelf.
From Unimak Island to
Port Moller, the dominant shallow water shrimp taxa were Crangonidae (D.
Armstrong, pers. observation, June 1982, R/V Miller Freeman), primarily
C. communis, C. alaskensis and A. dentata.
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