What are long-line fisheries?

As the name implies, long-line fisheries use a long line - a piece of rope or nylon - that lies in the water supporting baited hooks. There are two main types of long-lines:

Albatross and Giant Petrels scavenging fish offal from long-line fishing vessel

Surface long-lines are suspended about 200 metres below the surface from floats. They might exceed 100km in length and carry 3000 baited hooks suspended on 40m-long branch lines. Baited hooks are spaces about 50m apart and bob up and down in the water to attract fish. Surface long-lining is used all around the world to catch highly prized mid water fish like tuna and swordfish.

Bottom or ground long-lining is used to catch deep water fishes like ling, hake and Patagonian Toothfish. Bottom long-lines are heavier than surface long-lines and carry many more hooks on much shorter lines. Every year bottom long-liners set hundreds of millions of baited hooks into oceans inhabited by albatrosses.

Drowned black-browed Albatross

Albatrosses' awesome flying ability and vast ranges make it easy for them to follow fishing vessels - particularly when there's a free feed on offer.

As the baited hooks are deployed by the fishing trawlers, the albatross dive for the baits, the hooks lodge in the bill or throat and the bird is dragged under and drowned.

In the Southern Ocean, where most albatross species range, it is likely that tens-of-thousands of albatrosses and other petrel species are killed annually.

Surface long-lining is the biggest threat to wandering albatross - the slow-moving birds have time to attack the long branch lines floundering in the water. Bottom long-lining is less of a threat to wanderers as the heavier lines sink faster and they are out-competed by smaller, more manoeuvrable species like black-browed albatrosses.

Black-brows and grey-headed albatrosses are particularly vulnerable to long-lining - both surface and ground - as they are good divers and can reach the baits as deep as two metres down.

The birds are also inadvertently encouraged to hang around the ship as the offal from the cleaned catch is thrown overboard, providing a veritable banquet.

Wandering albatross hooked and drowned

The problem is most severe in the illegal long-line fishery for Patagonian Toothfish because the fishery occurs in defiance of the law and international agreements designed to protect fish stocks and bycatch species like seabirds. Clearly, it's unlikely that efforts would be made by these fishermen to safeguard seabirds from becoming hooked.

Measures to reduce albatross mortality in long-line fisheries do exist and have done for at least 10 years. The most effective are night fishing, flying lines of streamers behind boats to scare albatrosses off hooks, adding weight to long-lines so they sink faster, setting long-lines deep underwater and expelling offal discreetly.

However, experience has shown that educating fishermen about mitigation measures, though essential, is unlikely to make fishermen comply with conservation requests voluntarily. So it is vital that mitigation devices are easy to employ, cost-effective - and are legislated for by authorities. This summarises the focus of Peregrine's albatross conservation initiatives: grass roots development of mitigation devices; education; and advocacy for fisheries regulation.