Long~line gear was fished at 17 stations during the four
cruises.
Sixty "baskets" of 6-hook,
180 to 210-fathom mainline
gear with 16-fathom droppers were fished at each station.
The
catch rate ranged from 0.6 to 21.9 tuna per 100 hooks per set.
Details of the catch are given in Table 2.
Some of the skipjack
tuna used for samples were taken by live-bait fishing, whereas
the flying fish samples were obtained from specimens that flew
onto the ship's deck at night.
Samples of muscle and liver were dissected from the fresh
fish,
labelled,
placed in a plastic bag,
for transport to Christmas Island.
and frozen aboard ship
Here some samples were
weighed, dried in an oven at 95° C for 24 hours, reweighed,
ground and placed in a standard size plastic container for
counting;
other samples were frozen or dried and shipped to
the Laboratory in Seattle for further processing and analysis.
In most of the tuna-like fishes samples of light and dark muscle
and liver were analyzed separately.
Plankton and nekton samples were collected with one-meter
diameter plankton nets and a six-foot diameter Isaacs~Kidd midwater trawl.
Sixteen 30-minute surface plankton tows,
four 30-minute,
thirty-
50-meter plankton tows and one 30-minute,
100-
meter plankton tow were made with the one-meter open net.
Settling volumes, after the large organisms
fish,
etc.) were removed,
(jellyfish,
lantern
ranged from 73 to 1,150 ml per tow.