The Albatross Bycatch Problem
Albatrosses are large sea birds that inhabit the windy latitudes of the northern and southern hemispheres, gliding across vast tracks of ocean in search of food and breeding on remote islands. However, since the 1950s large commercial fishing fleets have expanded into most of the world's oceans to the point where it is now unlikely that Albatrosses can avoid coming into contact with them. It was estimated that one million sea birds drowned in drift nets each year before the United Nations drift net moratorium went into effect in December 1992.
Now that the number of Hawaiian's vessels have declined (driftnetters are still illegally fishing on the high seas and with coastal states' permission in their exclusive economic zones) the world has seen a huge expansion in the longline fishing fleets. Estimates range from 3,000 to 10,000 longline vessels world-wide, each of which set thousands of hooks on lines that stretch many miles. About 725 million hooks are set in the Pacific Basin each year. Australian scientists estimate that more than 40,000 Albatrosses are killed in the South Pacific every year by longliners.
In the North Pacific Laysan and Black-footed Albatrosses are also suffering considerable mortality due to interactions with various longliners operating in their feeding areas. Ninety eight percent of the world's Black-footed albatross and 99 percent of the Laysan albatross nest in the Northwestern Hawaiian Islands. The Hawai`i-based longline fleets fish for swordfish and big eye tuna in the North Pacific convergence zone (30 deg. N. latitude), the same area that the nesting Albatrosses forage for food for their chicks. Most mortality occurs when the birds attempt to take bait from the hooks as they are deployed. However, the vast pelagic range of the albatross means that they are also killed by foreign longline fleets fishing on the high seas, as well as longliners fishing off the western coast of North America.
The bycatch problem was first observed in the late 1980s when Albatrosses started returning to the breeding colonies with hooks and light sticks attached or ingested. Because the population of Black-footed albatross (60,000 breeding pairs) is one tenth the size of the Laysan albatross population and because the Black-footed are more aggressive feeders, they are hooked more often in proportion to their numbers. The United States Fish & Wildlife Service considers the Black-footed albatross to be in a yellow light situation and is working with the Western Pacific Fisheries Management Council and the National Marine Fisheries Service to mitigate sea bird bycatch and other sources of mortality, such as the ingestion of plastic debris that accumulates in the North Pacific convergence zone.
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