There has been no documentation of separate stocks, but there are suggestions of isolated local populations in other species. Aging of Pacific hagfish has not been done due to lack of hard body parts in the fish that would bear annual marks. Harvest Harvest is done with traps on longlines baited with dead fish. Larger traps made from plastic buckets or barrels are becoming more popular. Most of the catch is frozen whole and shipped to the Republic of Korea.
Some harvesters add chemicals to containers to kill the hagfish quickly.
While adding the chemicals controls biting among the hagfish and improves the skin quality, it renders the fish unsuitable for human consumption. The most efficient trap design had more than one entrance funnel, escapement holes only in the area around the funnel, and shorter funnels made of solid material. In Canada, patterns of CPUE suggest there may be biological factors such as seasonal movements or spawning periods that affect catch rates. Another barrier to the west coast fishery is a ban on the use of imported hagfish meat for human consumption into the Republic of Korea. In Oregon, hagfish may be harvested using traps that include a biodegradable escape panel.