Bluefin tuna

The Atlantic bluefin tuna (Thunnus thynnus) is a species of tuna in the Scombridae family. It is variously known as the northern bluefin tuna (mainly when including Pacific bluefin as a subspecies), giant bluefin tuna (for individuals exceeding 150 kilograms or around 330 pounds) and formerly as the tunny.

Techniques

Boat
Big-game fishing requires a boat of sufficient seaworthiness and range to transport the crew to the fishing grounds and back. Boats that fit these requirements may be as small as the 18 to 21-foot trailerable boats commonly used along the Adriatic coast or big usually used for spending longer period of time at the open sea.

Trolling
Fish are enticed by trolling fishing lures (designed to resemble squid or other baitfish) or baits behind the boat. Multiple lines are often used. Outriggers were designed to spread the lines more widely. The outrigger holds the lines further away from the boat’s wake, setting lures into clearer water thus making it easier for fish to target in on available lures.

Chumming/chunking
Chumming, or chunking, is the process of throwing pieces of bait fish overboard to attract larger game fish. This is called Berley in Australia.

Fighting the fish
Once a fish is properly hooked on a line, a somewhat tricky task as often initial nibbles only partly hook the fish, one of the fishermen attempts to reel it in. The captain assists by maneuvering the boat so that the fish remains astern (behind the boat), while other members of the crew race to reel in the other lines so as to avoid tangling with the angler reeling in the fish.
Most of the time, the fishing line used for sport fishing has a breaking strain less than the maximum force the fish can apply to the line. The fishing reels therefore have sophisticated drag mechanisms which allow the line to escape if the fish pulls on it, but keep the specified tension on the line. When hooked, most fish will circulate in different directions, and when they are not pulling away from the boat the fisherman can take the opportunity to reel in some of the line. Eventually, if the fish tires and has not broken the line, they will be reeled in; however, the challenge does not end there. Hauling a heavy, powerful, and still very much alive fish on board the boat represents a considerable challenge, unless the fish is tagged and released. Strategies include: gaffing, pulling it in with ones hands, and if it is a smallish game fish, a net.
The fish can be fought with or without a game-chair. With a game-chair, the angler sits in a specially designed chair at the stern of the boat, and places the butt of the rod into a gimbaled mount. Most rods used in this manner are quite long. The older and more classic models had straight rod butts. More contemporary models have bent rod butts, which give a more convenient angle for fighting the fish when the rod is placed in the mount. With large fish, this can still represent a considerable challenge, but “stand-up” game fishing, without the assistance of a chair and with the seat mount replaced by a harness, requires a good deal of strength and endurance, as well as body mass.