Vol. 53 - Alaska Resources Library and Information Services

Larvae. Larval red king crab distribution and relative abundance were
documented with standard net hauls over transects designed to fill
existing data gaps and to establish a continuing program. The primary
sampling method for collecting larval red king crabs was the standard
oblique bongo net tow in order to facilitate comparisons with previous
Alaskan plankton and larval decapod collections both in Bristol Bay and
off Kodiak Island. The nets were fished in CALCOFI fashion (Smith and
Richardson 1977) to a depth of 80 m, or 10 m above the bottom, whichever
was less. Eighty meters was selected as the bottom depth to be fished
because crab megalopae are known to vertically migrate down to a depth
of at least 70 m, but apparently not to 90 m (Ito and Ikehara 1971;
Kendall, et al. 1980). The objective of the bongo net collections was
to sample all of the larval crabs in the water column independent of
time of day when sampled.
The bongo nets used were paired 0.333 mm (333) and 0.505 mm (505) mesh
nets 60 cm in diameter with a length:width ratio of 5:1. These mesh
sizes have been used in previous Alaskan plankton and larval decapod
collections (Armstrong, et al. 1981a; Haynes 1974; Kendall, et al. 1980).
A TSK and/or a General Oceanics "bullet" flowmeter was attached at the
mouth of one or both of the nets. Collections were preserved in the
field with 4 percent formalin and BHT added to preserve color of the
larvae.
Two additional sampling devices, a Tucker trawl and a neuston net, were
also utilized at two stations to characterize diel vertical stratification,
which may be important for potential oil impact assessment. The
sampling design utilized followed that of Kendall, et al. (1980) to
assure a good comparison. The mesh size of both nets was 0.505 mm and
the depths sampled were 0, 10, 20, 30, 40 and 50 m. Sampling was done
at dawn, midday, dusk and midnight.
Epibenthos. All of the epibenthic sampling was conducted from either
the NOAA Ship Miller Freeman and its MonArk launch.
Sampling days
303