Trolling
Posted by Andrew via Email at 10:20 PM, August 08, 2004
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| (C) Greenpeace |
"It's very easy, you just take the hook out, and release it," explains Bill, who works on a line troller. We've been talking about three different industrial tuna fishing techniques: line trolling, long lining and purse seining.
The kind of ship Bill works on has fishing lines, up to 18 feet (5.4 meters) long attached to booms that fold down to a horizontal position. On the end of the lines is a selection of lures. The lines are attached to a bell. When fish pull the lines, the bell rings and the crew rushes out to pull in their catch.
Larger photo
"If we catch an undersize fish we have to keep it alive and throw it back in the water", confirms Johnny, one of Bill's crewmates. "We know that's the main recourse, our future."
Johnny used to work on a different kind of fishing ship, a long liner. Long liners put out, for lack of a better description, very long lines. Each long line has shorter lines attached to it with baited hooks on the ends. The main line can be a hundred miles long. "So two reels, that's two hundred miles," says Johnny about his old boat. "That's six thousand, almost seven thousand, hooks. Yup, it's a lot of work, man."
To set the lines takes hours. By the time they're reeled back in, a lot of the fish hooked are already dead. A good captain can try to target a specific species, by setting the line deeper or shallower for example, but they catch non-target species anyway, which are often thrown overboard dead.
"We don't catch any sharks with these," Bill says holding up a tuna lure. "We only catch albacore." Sharks are caught accidentally by legitimate long liners, and are sometimes even targeted deliberately, for their fins. Birds, turtles and assorted (non-target) fish also end up as unintentional catch.
Then there are the purse seiners, often bad mouthed by fishermen working on both the long liners and the trollers. "With the purse seiners, there's no discrimination," says Bill. "They catch it all and it all dies". He's barely exaggerating. By-catch (unwanted/non-target species) is a major problem with purse seiners. They can take huge volumes of fish (some catch 11,000 tonnes a year), and although they target tuna, everything in the net is brought in. The process is very democratic with no regard for age, size or species - it's all hauled on the deck in a big net sausage.
I suspect that Johnny didn't want to say anything bad about his fellow fishermen, but in the end he did volunteer that there are big problems with how long lining and purse seining is done, saying, "They kill whatever, the baby fish…They don't think about the world, our future".
Given it's advantages in terms of sustainable fishing, targeted catch, and generally better working conditions for the crew, you might wonder why the global fishing industry has shifted away from trollers (purse seiners and long liners are now far more numerous). Partly it's because trolling is more labour intensive. It's also because line trolling only targets fish near the surface. So, it is certainly not the whole solution, but does show that, if properly regulated, highly targeted sustainable fishing can be done profitably.
