Observers used random sampling methods to choose hauls to sample. Once those hauls were selected, observers sub-sampled for the species composition of the whole haul. Generally, a small sub-sample, approximately 300kg, is obtained from each sampled tow. Within that sample species are identified, counted, and weighed. Raw data are entered into the observer database located in the AFSC in Seattle.
Raw data are available as are the data extrapolated from the sample to the haul.
The area ranged from 40 km off Dixon entrance in the east to 20km off the Islands of Four Mountains in the west. These data were collected using a Nor eastern high opening bottom trawl net with rubber bobbin roller gear on two or three chartered vessels. Station locations were allocated for each stratum from a grid of points laid over the survey area. Within each stratum the sampling density was assigned based on expected variances of abundance for selected species from past surveys. The stations were then randomly selected within each stratum and divided equally between the number of vessels surveying during that year.