Satellite Tracking Finds Albatrosses' Deadly Zones
JOHANNESBURG - Satellite tracking data have pinpointed parts of the world where longline fishing trawlers and albatrosses cross paths, often with fatal results for the majestic sea birds, a report released on Wednesday said.
More than 300,000 seabirds, including 100,000 albatrosses, are believed to drown each year because they are lured by baited hooks and then pulled under the water.
"Identifying areas where albatrosses and fishermen overlap is a crucial conservation step," said Cleo Small, international marine policy officer at BirdLife International.
The report, "Tracking Ocean Wanderers," was collated by UK-based BirdLife International and the Royal Society for the Protection of Birds (RSPB).
It uses satellite tracking data on 16 species of albatross and three petrel species, all endangered by commercial and pirate longline fishing fleets which use nets up to 130 km (80 miles) long carrying thousands of baited hooks.
It identifies hot spots where both longliners and large numbers of seabirds are found in waters around New Zealand and southeast Australia, the southwest Indian Ocean, the south Atlantic and the north Pacific.
Conservationists say that fairly simple measures can be used by longliners to reduce seabird mortality.
"They can thaw out their bait, which will then sink faster and not attract birds, or they can attach weights to sink the bait," said BirdLife's Richard Thomas.
He said Brazilian fishermen use a colourful but effective technique that involves dying their bait two shades of blue.
Birds tend not to see blue but fish do. The first dye keeps the birds away but is water soluble and bleaches after the bait sinks.
This leaves a fat-soluble blue dye which makes the bait more attractive to the fish, so both fishermen and birds win.
Albatrosses are slow breeding, so there are fears that longliners are killing some species faster than they can reproduce.
All 21 albatross species are officially classed as under global threat of extinction.
The elegant white gliders are famed for their large wingspan and the long ocean journeys they make. The wandering albatross has a wingspan of up to 11 feet (nearly four metres) -- the broadest in the world.
The report also highlighted the huge distances travelled by some species during migration -- the northern royal albatross can fly up to 1,800 km in 24 hours and the grey-headed albatross can circle the globe in 42 days.