Executive Summary - Department of Invertebrate Zoology

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Neuston collections were obtained every th .ee hours for a 24-hour
period at each station during each quarterly cruis_ . At stations D1,
N3, and F2 during the second year only a single neuston tow was made,
in conjunction with bongo sampling . The neuston sampler, designed at
Woods Hole Oceanographic Institution, consisted of two
hyc+rodynamically-shaped . foam-filled floats connected by an endless
fiberglass belt, accommodating a standard one-meter plankton net and
towed by a four-point bridle . n 505 um mesh net was employed in all
neuston sampling . The unit sampled the surface laver to an
approximate depth (floating depth) of 12 cm and a width of one meter .
Tows were made from an extended boom in a widely circular track Zo
keep the net away from the ship's wake and, exc- . where abundance of
salps or ctenophores dictated a shorter tow, we• :` 20 minutes
duration .
Collected samples were washed into buckets, where they were
inspected for tarballs and large, readily identified species .
Tarballs, if present, were removed to labelled plastic zip-bags and
frozen . Large species, if present, were transferred to acid-washed,
teflon-capped jars and frozen for trace metal and hydrocarbon
analysis . A maximum of two species was selected at each station, with
specimens accumulated for a given station through the eight neuston
tows at 24-hour stations . Numbers and identity of *removed specimens
and the occurrence cf tarballs were noted on collection log sheets .
Sediments
Sediment samples for grain size, organic carbon, and nitrogen
znalyses were collected at each grab station . At each station, 12
replicate 0 .1 m2 Smith-McIntyre grab hauls were s ..ade except at some
deep stations where, because of long haul timP, few,~r hauls were made .
Into each of these successful grabs, a 3 .5 cu inside diameter clear
acrylic core was inserted, removed, and capped an both ends for grain
size analysis . The cores generally contained the top 10 cm of
sediment . During the first year, cores from the six grabs taken for
trace metal or hydrocarbon samples, usually the first six, were sent
to the USGS, Woods Hole, where a single grain size analysis was
performed on composited aliquants from the cores and the remaining
material returned to VIMS . At VIMS grain size ana .'vses were performed
on all six sediment samples from the grabs taken :ar faunal analysis
and two of the individual samples returned by USGS . During the second
year all twelve sediment samples were analyzed at VIMS .
Organic carbon and nitrogen samples were collected in a similar
fashion but in smaller diameter core tubes (2 .2 cm inside diameter) .
Gue core sanple each was taken from the six grabs collected for
analysas of macrobenthos . Samples were quickly frozen and remained so
until analysis .
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