Tug, glad you brought up the high seas gillnet fisheries. After I graduated from the UW in 1978, the first little job I had was as a fisheries observer on a Japanese salmon mother ship in the North Pacific. Four motherships were fishing and each mother ship had forty three 90 ft gillnet boats returning each day to unload their catch onto the monthership. Each gillnet boat fished about nine miles of gillnet. Monofilament gillnet with about 4 1/2 " stretch mesh. I did this each summer from about 1979-1985. I was able to sample and get the total weight of all the species of salmon off half of gillnet boats. I was employed by the UW but a fellow named Mike Dahlberg who worked for NMFS in Juneau (Auke Bay) was my supervisor. He was the one who met with the Japanese each year in the off season to discuss and agree on the sampling we did.
One reason I am bringing this up is because we are discussing steelhead. The first year I did this job Dr. Dahlberg said that the Japanese clamed they didn't catch any steelhead in their gillnets.The Japanese finally admitted they and was able to take mesurement s off 50 steelhead each summer. The areas where these fish were caught extended the range of North American steelhead at that time.