To give you a little context of the area I thought it might be helpful to teach you about the different types of commercial fishing. There are four that I know of, although I am certain that there are more.
2. Gill net
4. Power Troller
1. A Seiner is named for its net, a seine net. It has floats that keep it up, the put the net into the water and use a seine skiff to drive the net all the way out, then the encircle a school of fish and pull together the end of the net until they have a massive haul of fish. If you have seen Finding Nemo there is a moment in the movie when all the fish swim against a net, they are caught in a seine net. Usually seiners take multiple people to operate, because you need someone to drive the seiner, someone to drive the seine skiff and multiple people to deal with the net and all the fish that they haul in. In Alaska, most seiners are going for salmon.
2. A gill-netter is also named for it’s net, a gill net. Gill netters run what are called sets. They drop a net that hangs vertically in the water and leave it there for several hours. The net is held up by buoys to make sure that it doesn’t sink. The gill net works quite simply, the holes on the net are designed so that a fish can put its head through the net, it can’t fit its whole body, so as soon as the fish tries to back up the net catches it by the gills. The gill-netter comes back to the net after several hours after some fish have hopefully tried to swim through it. They pull up the net and gather all the fish that got caught. In Alaska, most gill-netters are going for salmon.
3. A longliner is named quite accurately. Like gill netters, long liners run sets as well. They have a very long line that has baited hooks on the line every 10-15 feet, that long line is anchored to the bottom so that the hooks are close to the bottom. Similar to a gill-netter, a long liner will set their lines and then return after several hours in hopes of multiple fish being attached to the baited hooks. Most long liners, in Alaska, fish for halibut, which is a bottom fish that can grow up to the size of 500 lbs and can be bigger than the bed of a pick up truck.
4. A power troller is a bit different than the other types of commercial fishing. Trolling is when you pull bait, or lures behind the boat as you go about 1-2 knots (1 knot = 1.1 miles per hour). Most people experience trolling with 4-6 people on a boat. Each person will have a fishing road and they will sit and watch their line as the boat moves slowly in hopes of pulling the bait/lures by some hungry fish. Power trolling is trolling on steroids. Whereas trolling normally features one hook per line, power trollers will put a hook on the line every 5-10 feet. If they have one piece of line out, they could have 10-20 hooks on that line in hopes of catching fish at different depths. They also use something known as a downrigger. A downrigger is attached to the line by a clip. The downrigger is dropped to a specific depth so that the person fishing can know exactly what depth they are fishing. Instead of pulling in massive amounts of fish like the seiners and gill-netters, power trollers are catching one fish at a time, they are just using 50-60 hooks at as many depths to increase the likelihood that they will see a fish.
There are surely more types of commercial fishing, and significantly better ways to describe how and what they do but hopefully this gives you enough of a background to understand commercial fishing in Alaska.