Purse Seining is a method used to catch TUNA. A seine or net is drawn out from the fishing boat and around the school of TUNA. Weights carry one edge of the seine deep into the water. When the fish are surrounded, the bottom of the seine is drawn together or pursed, so that the fish are trapped and hauled aboard the boat. This method accounts for about 80 percent of the commercial catch of Light Meat TUNA.
Long-Lining also accounts for about 80 percent of the world’s Albacore TUNA harvest. A very long line (as much as 130 kilometers or 81 miles) supported by floats and marked with flags is set out from a fishing boat. Branch lines attached to the long line are sunk with baited hooks to depths of 55 to 150 meters. It may take as many as 20 hours to set a line, and longer to retrieve it with its catch.
Pole and Line or Trolling are other means used to catch TUNA commercially. Live bait (anchovies or sardines) are dumped from the fishing boat to bring TUNA into a feeding frenzy. This is called “chumming”. Fishermen on the boat drop lines with barbless hooks into the school of fish, and bring them aboard as they are hooked.
