Accessible document

GETTING TO KNOW OREGON'S COMMERCIAL FISHERIES

Traps

Writers: Ginny Goblirsch and Steve Theberge
Artist: Herb Goblirsch
Editor: Sandy Ridlington
Design: Rick Cooper

© 2008 by Oregon State University (revised)
ORESU-G-08-012

Trapping Crab

Dungeness crabbing is seasonal, usually from December 1 to August 15. The majority of the catch occurs during the first two months of the season. Most vessels participate in a combination of other fisheries during various times of the year.
Crabbers are rigged with a large hydraulic block (crab block or gurdy). Mounted just behind the pilot house, it is used to haul in pots. Because the catch is delivered to the market live, the vessels have a circulating seawater system in their holds. Most pots are circular, measure three to four feet across, and weigh from 75 to 120 pounds. The 3⁄4-inch welded steel frames are wrapped with strips of used inner tube to protect the steel from corrosion. Stainless steel wire is used to weave a three- to four-inch-diameter mesh over the wrapped frame. Tunnels on opposite sides allow crabs to enter the trap. The traps are baited with herring, squid, or razor clams. A ring on the top side gives undersized crabs an escape route. A single line with usually two cylindrical plastic buoys is attached to the trap. Buoys are marked or colored to distinguish one vessel’s pots from another. Each fisherman has an ODFW-registered number on the buoys.

Crab boats typically have a two- to four-person crew. The crew pushes the pots over one at a time as the vessel follows a particular depth line, usually between 3 and 80 fathoms (a fathom equals six feet). Pots are retrieved one at a time by snagging the buoy line with a hooked pole. The line is placed in the block, which hauls the pot into the vessel. Each vessel is allowed to fish a certain maximum number of pots (check current regulations). When the traps come up, they are emptied, the catch is sorted, and the pot is rebaited and put back out. A two-person crew can average 30 to 40 pots an hour. Traps can hold up to 60 crabs. Crab pots are checked every one to seven days, depending on fishing conditions.

Managing the Crab Fishery

The fishery is managed with limited entry permits (fishermen need a permit to fish for crabs, and only 450 permits are issued for this fishery). Furthermore, the fishery is managed by size and sex restrictions, ensuring a healthy population. Only male crabs are harvested, and the shell on the crab has to be at least 6 1⁄4 inches. This size is reached at four years of age and allows the crab to reproduce for one to two years before being harvested. The crabs can live to be 9 to 10 years old. Landings of Dungeness crab range from 3 million to 18 million pounds, with the average catch at 10 million. Dungeness crab populations fluctuate a great deal from year to year, depending on oceanographic conditions.

Dungeness crab rivals Maine lobster as a gourmet item, and in recent years a live crab market has developed.

Trapping Sablefish

Pot fishing is one method used to harvest sablefish. Vessels are generally large (over 60 feet) because the pots are large and use up a lot of deck space. Trapezoidal, basket-shaped, and rectangular pots are used. Basket-shaped pots have collapsible bottoms so more pots can be stacked on deck.

Gear includes a hydraulic block or line hauler, an overhead hoist for lifting pots, and large buoys and flag poles. Reels are used to hold ground line if the line is not coiled on deck or in the hold. Pots are baited with hake or squid. The pots are run on a longline system with up to 50 pots attached to each line. The lines are set in water depths of 200 to 600 fathoms and are weighted at each end with an anchor. They are marked with surface buoys and flag poles. Sablefish pots have self-destruct panels that are designed to fall apart if the trap is left in the water too long. This keeps the trap from continuing to catch fish if the trap is lost. And fishermen have voluntarily included “escape rings” to allow smaller fish to leave the traps.

Managing the Sablefish Fishery

Sablefish are federally managed under a limited entry program. Harvest is divided among different gear types.