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Vol. 53 - Alaska Resources Library and Information Services

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A total of 317 crabs age 3 <strong>and</strong> younger was collected during the study.<br />

The distribution of these crabs, divided into apparent age groups, is<br />

shown by cruise in Figures 3.5-4, 3.5-5 <strong>and</strong> 3.5-6. All of the crabs in<br />

this size range were collected at 50 m or shallower depths, primarily in<br />

the four easternmost subareas: Port Moller (PM), Port Heiden (PH),<br />

Kvichak Bay (KB) <strong>and</strong> Togiak Bay (TB). The numbers of crabs collected<br />

per cruise from each of these subareas are summarized in Table 3.5-2.<br />

The KB <strong>and</strong> PH subareas yielded the greatest total numbers of small<br />

crabs, partially due to the greater number of samples taken in these<br />

areas (Table 3.5-1). Catch per station data, calculated as the sum of<br />

the mean catches per station divided by the number of stations sampled<br />

per subarea, are also presented in Table 3.5-2. Crab densities in the<br />

KB <strong>and</strong> PH subareas were generally higher than in other subareas during<br />

each cruise, with the exception of the TB area during April-May. The<br />

high value for the PH subarea during cruise 83-5 is primarily the result<br />

of a single catch of small crabs (59) at station PH230, using the<br />

trynet. The high value for the KB subarea during the same cruise is the<br />

result of six rock dredge hauls in the vicinity of station KB2*4 that<br />

each contained from seven to 37 small crabs, <strong>and</strong> a single trynet haul<br />

at station KB250 that contained 13 small crabs. The large catch at<br />

station PH230 consisted of almost equal numbers of YOY individuals <strong>and</strong><br />

one year-old (1+) individuals, whereas the majority of crabs from the KB<br />

stations were young-of-the-year (Section 3.4).<br />

The relative abundance of the age groups of juvenile crabs over the<br />

length of the study is presented in Figure 3.5-7. The catch per<br />

station data represent the mean number of crabs per station divided by<br />

the number of stations sampled in the entire study area for each of the<br />

three cruises. The greatest changes were the increase in numbers of<br />

young-of-the-year, 1 <strong>and</strong> 1+ crabs <strong>and</strong> the decrease in numbers of age 3<br />

crabs. Age 2 <strong>and</strong> 2+ crabs were caught in very small numbers during<br />

April-May <strong>and</strong> June only.<br />

357

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