September 23, 2013 — The U.S. is setting the standard for ecologically sustainable longline fishing. Now it's time to make sure the rest of the world gets onboard.
The United States is the world leader in innovations to reduce longlining bycatch of birds, but we haven't come nearly as far with protections for non-target fish and sea turtles. Many other nations don't use mitigation for any kind of bycatch. Largely as a result, about half of the world's petrels and most of the albatrosses are threatened with extinction.
There's no bycatch problem with New England longlining because the anchors sink the hooks to the ocean floor before the few diving birds in the area can grab the bait, because non-target fish can be released alive, and because there are relatively few sea turtles off New England.
But other longliners can face daunting challenges. The last thing they want is to waste hooks and fishing time on non-targets, so they're apt to be receptive to mitigation methods. "We try to extract ideas from fishermen and sometimes move those ideas in different directions, working with them on their boats," Melvin says. "We get them involved in a problem-solving process. I really wanted to zero in on streamers, fine-tuning the design to make it more effective. Off South Africa there were several albatross species we were concerned about. They couldn't reach the bait, but white-chinned petrels would bring it up and get mobbed by the albatrosses, which would then get hooked and drown."
So working with Japanese boats in a major study from 2008 to 2010, Melvin's team and the fishermen figured out a way to extend the streamers, and they lowered the hooks beyond the streamers by placing weights on the branch lines that hung off the main longline. This, combined with night fishing, virtually eliminated bycatch. Melvin says these innovations seem to be catching on well with Asian fleets and are now accepted as best practices.
Off Alaska, longliners targeting Pacific cod, sablefish, and halibut were killing huge numbers of seabirds, including critically endangered short-tailed albatrosses. With no large deep-diving petrels in the Northern Hemisphere, Melvin's team was able to reduce bird bycatch by 80 percent with its standard streamer design. On the U.S. West Coast the team is teaching streamer use to U.S. sablefish longliners operating about 20 miles out, where the continental shelf falls away and black-footed and Laysan albatrosses feed.
Most of the remaining problems are with foreign and illegal vessels operating in the Southern Hemisphere, home to most albatrosses. With minor exceptions, these birds breed at mid or high latitudes, but they can feed thousands of miles from their nests. For instance, BirdLife International has tracked wandering albatrosses on foraging trips that last 22 days and span 2,237 miles from the Antarctic to the tropics. In Samuel Taylor Coleridge's beloved poem, it was probably a wandering albatross, patrolling the southern fringe of its range, that the ancient mariner dispatched with his crossbow.
Read the full opinion piece at Audubon Magazine