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Vol. 53 - Alaska Resources Library and Information Services

Vol. 53 - Alaska Resources Library and Information Services

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consisted of 24 hours on all cruises with the use of two scientific<br />

crews. Each station was surveyed prior to bottom sampling with the<br />

ship's 50kH Simrad fathometer in order to assess the trawlability of the<br />

bottom <strong>and</strong> determine the selection of sampling gear.<br />

Samples of epibenthic organisms were obtained with trynet trawls <strong>and</strong><br />

rock dredges; these gear are described in Table 2.1-2. The trynet was<br />

generally the preferred gear for apparent smooth, flat bottoms, whereas<br />

the rock dredge was used where the bottom appeared to be rocky or<br />

broken. A number of trynets were damaged or lost when sampling was<br />

attempted on rough bottoms. Several stations were sampled with both<br />

gear types in an attempt to compare their performance. The scope<br />

(towing wire to water depth ratio) <strong>and</strong> the towing speed were adjusted by<br />

the Miller Freeman fishing crew to maximize gear efficiency. The trynet<br />

was towed with scopes ranging from 3.0:1 to 4.5:1 <strong>and</strong> ship speeds of 2.5<br />

to 3.5 knots. The rock dredge was towed with a scope of 4:1, <strong>and</strong> ship<br />

speeds in the range of 1.0 to 3.0 knots.<br />

Quantitative try net <strong>and</strong> rock dredge samples were placed on a sorting<br />

table, characterized in field notes, <strong>and</strong> sorted to the lowest possible<br />

taxonomic groups. Voucher specimens of many taxa were preserved for<br />

further identification or verification. Samples were carefully searched<br />

for small red king crabs. Taxonomic groups were weighed on a large<br />

fisheries deck scale (for large organisms or large samples) or a triplebeam<br />

dial-type gram scale (for small organisms or samples). All<br />

organisms were counted, with the exception of colonial forms or small<br />

attached fauna. Very large samples were subsampled, <strong>and</strong> the total<br />

sample weights <strong>and</strong> counts were extrapolated from the subsample data.<br />

All red king crabs <strong>and</strong> Tanner crabs were measured for length (king<br />

crabs) or width (Tanner crabs), <strong>and</strong> information on sex, maturity,<br />

shell condition, egg condition <strong>and</strong> external parasites was recorded.<br />

Individual weights were obtained for all king crabs except the very<br />

small young-of-the-year, which were frozen for later analysis. Lengths<br />

304

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