Alaska's Commercial Salmon Fishery

In Alaska, salmon come first. Alaska has a long and successful track record of managing and conserving its abundant salmon resources. Record salmon runs with a recent average annual catch of 165 million salmon is the proof of this successful approach.

Salmon fishing permits are issued to individuals, not corporations, through the "limited entry permit system". The total number of available permits for each fishery is strictly limited. Fishermen may not own more than one salmon permit for the same gear type and area. This creates a fishery made up of many individuals and families.
Three main gear types catch Alaska salmon: trolling, gillnetting, and purse seining. All commercial salmon fishing boats are relatively small vessels; averaging 30 to 50 feet.

Trollers use long trolling poles to pull or troll 2 to 4 deep weighted lines through the water, each with 8 - 12 leaders attached. At the end of each leader there is a lure or baited hook. Boat size varies from small skiffs to vessels of 50 feet or more with most ranging between 25 to 40 feet.
Trollers primarily target king, coho, and pink salmon as they enter Alaskan waters on their way to the spawning grounds. Trollers catch a relatively low volume of high-quality fish. The fish they catch are bright and vigorous from fresh ocean waters. They are often
sold dressed, or filleted in the fresh or fresh frozen market.
Gillnetters set curtain-like nets in the water suspended from a float line at the surface and a weighted lead line along the submerged bottom edge. Nets vary in length from 900 to 1800 feet long. The net's mesh openings are just large enough to allow an adult fish head to get through and become entangled at the gills.

There are two types of gillnets; driftnets that are free floating from boats, and setnets that have one end attached to the shoreline. Boat size is limited to 32 feet or less in Bristol Bay; otherwise, the average range is 30 to 40 feet. Gillnetters primarily harvest sockeye, chum and coho.
Purse Seiners use a large floating net, pulled and set in circle by a power skiff, to surround schooling salmon. The weighted "purse line" at bottom of the net is drawn closed to contain the fish. The net full of fish is then gathered to the boat through a highpowered hydraulic block.

Source : articlesbase