Introduction
All but seven of the world’s 22 species of albatrosses are threatened with extinction. The main threats are incidental mortality (bycatch*) in commercial fisheries. British Antarctic Survey science and technology underpins international efforts to conserve these charismatic birds.
Why are albatross populations declining?
Each year, tens of thousands of albatrosses are drowned as they scavenge behind fishing vessels. Both trawling and longlining – where fishing vessels set lines containing thousands of baited hooks – attract seabirds looking for food. Many albatrosses are dragged to their death as they swallow these baited hooks. Others are injured or killed in collisions with trawler cable. Plastic waste ingested at sea, past introductions of non-native, invasive species such as rats, mice and cats onto breeding islands, and disease pose additional hazards.
How serious is the problem?
Fifteen of the world’s 22 albatross species are threatened with extinction, and six are ‘Near-threatened’ according to the World Conservation Union (IUCN). Two species – the waved and Tristan albatross – are critically endangered. However, several of the populations that are declining most rapidly breed on the UK Overseas Territories in the South Atlantic. On the subantarctic islands of South Georgia, for example, three species of albatrosses monitored by British Antarctic Survey (BAS) are declining at between 2% and 4% a year, and are included among less than ten global “Priority Populations” by the Agreement on the Conservation of Albatrosses and Petrels (ACAP).
How do we know?
Since the early 1960s, BAS scientists have monitored albatross populations at Bird Island, South Georgia – home to some of the largest, and best studied, albatrosses in the world. During this time a range of innovative techniques have been developed to understand breeding and foraging ecology. The return rates of ringed birds give scientists an indication of breeding frequency and survival rates, while tiny tracking devices reveal the vast areas of ocean covered by these birds in search of food. Pioneering satellite tracking studies by BAS scientists in the early 1990s gave the first real evidence that some albatrosses spend substantial amounts of time foraging behind commercial fishing vessels. Since then, BAS has accumulated a wealth of tracking data, used recently in one of the most comprehensive studies to date of fisheries overlap and bycatch risk across the Southern Ocean.
Why are albatross populations so vulnerable?
As well as being the largest of all seabirds, albatrosses are also the longest lived, some surviving for more than 60 years. They take many years to reach sexual maturity, not breeding until they are around 10 years old. Although most breed annually, nine species – including the wandering albatross – lay only one egg every two years, and it takes the best part of a year for a young albatross to leave the nest. Because chick production is so slow, even small increases in death rates among adults will cause populations to decline.
What action is being taken?
The international Agreement on the Conservation of Albatrosses and Petrels (ACAP) came into force in 2004 and is coordinating efforts to address the conservation crisis faced by these birds. Argentina, Australia, Brazil, Chile, Ecuador, France, New Zealand, Norway, Peru, South Africa, Spain, the UK and Uruguay have ratified the treaty, thereby agreeing to take specific actions to reduce bycatch and remove introduced species from nesting islands. The Albatross Task Force, part of the BirdLife International Global Marine Programme engages directly engages with fisheries operators and crew to try to reduce bycatch rates. BAS has very close links with both ACAP and BirdLife International, frequently providing data and advice to help develop effective conservation management.
But what are fishing companies doing about it?
Many commercial fishing companies have introduced measures to reduce seabird bycatch rates. On longliners, these include: fitting streamer lines, which flap behind boats and deter birds from trying to feed on baited hooks; weighting hooks so they sink quickly beyond the reach of birds; setting baits underwater; setting lines at night, when albatrosses are not feeding; keeping waste bait and offal on board; and introducing closed seasons for fishing.
Are these measures making a difference?
Yes, to some extent. For example, the Government of South Georgia and South Sandwich Islands applied the scientific evidence and advice provided by BAS scientists to introduce mandatory mitigation measures for its commercial fishery. During the late 1990s, 6,000 seabirds were killed each year by fishing vessels around South Georgia, but the subsequent introduction of mitigation measures has successfully reduced seabird bycatch to negligible levels since 2006. Efforts by the Albatross Task Force have led to substantial reductions in seabird bycatch rates off southern Africa.
What more needs to be done?
Even though albatrosses may be safe around South Georgia, the birds range so far in search of food (sometimes over 1,000 miles a day) that they will inevitably encounter fisheries that do not currently use mitigation measures. As a result, South Atlantic albatross populations are still falling. The challenge now is to persuade other national and international bodies responsible for managing fisheries within the nonbreeding areas of these birds to introduce and enforce mitigation measures.
Fact file
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- Albatrosses belong to a group of birds known as Procellariiformes, or ‘tubenoses’. Tubes on their beaks allow them get rid of excess salt, so they never need to drink fresh water.
- Three of the world’s 22 albatross species live in the North Pacific and there is a tropical species that breeds on the Galapagos Islands. No albatrosses breed in the North Atlantic.
- BirdLife International estimates that longlining kills around 100,000 albatrosses each year.
- Albatrosses cover vast distances when foraging. When breeding, wandering albatrosses range from sub-tropical to Antarctic waters on trips of up to 10,000km in 10-20 days. In the non-breeding season, many species (including wandering and grey-headed albatrosses from South Georgia) migrate long distances, some travelling right around Antarctica.
- With wing spans of up to 3.5m, albatrosses have the longest wings of all birds. They are also amongst the longest lived.
*Bycatch is the term used to describe the non-target species such as seabirds, turtles, fish and marine mammals caught or killed in fishing gear.