News for October, Albatrosses in Trouble

Bird On! News
10th October 2000

David Tomlinson

• Kiwis on the Up
• A honey buzzard autumn

Albatrosses, or rather the threats to their survival, remain in the news. The British Birdwatching Fair at Rutland in August played an important role in raising awareness of the plight of albatrosses, petrels and shearwaters from long-line fishing, and raised many thousands of pounds towards BirdLife's "Save the Albatross" campaign. Now the RSPB has stepped in with its own fundraising project in support of the same campaign. (The RSPB is BirdLife's UK partner and the two charities work closely together.)

RSPB members have received what can best be described as a mini-poster that unfolds to reveal a wandering albatross in flight. It does give some idea of the extraordinary size of this giant seabird which has a wingspan of 11ft, or 3.5m. The accompanying text explains the problem:

"Worldwide, thousands of albatrosses are drowning on commercial longlines each year. These magnificent seabirds are attracted to the fish used to bait the hooks and, as they plunge down to take it, are hooked and dragged beneath the waves. As a result the wandering albatross - the largest of the world's albatrosses - is seriously threatened with extinction. And with some longlines measuring up to 100km in length and carrying thousands of hooks, most other species of albatross are being put at risk of global extinction too. In fisheries terms, the seabird toll is listed simply as the 'by-catch'. But to us, it's the unacceptable cost of longlining."

Ironically, longlining was thought to be more acceptable than netting as it reduced the risk of dolphins and turtles being caught unwittingly and drowned as 'by-catch'. We now know that hundreds of thousands of seabirds are being killed unnecessarily each year, an unacceptably high price to pay for our tuna. There are ways of making longlining less dangerous to seabirds (such as only fishing at night - albatrosses are diurnal feeders).

I have been lucky enough to have seen many albatrosses on the southern seas (only rare vagrants ever appear in the North Atlantic). I saw my first wandering albatross off the Falkland Islands but it was in Australia's Tasman Sea that I enjoyed close encounters with these birds during a pelagic birdwatching expedition. The albatrosses, along with thousands of shearwaters and petrels, were attracted to our boat by chum. Chum is a mixture of sheep fat and other unsavoury abattoir waste that seabirds consume with great enthusiasm. Remarkably, these birds find the chum by smell and can be attracted from miles away.

One individual wanderer that came to our boat consumed about five pounds of fat. We left this bird floating happily on the water where it seemed likely to remain until it had digested some of its huge meal. Whether it could still fly after consuming so much food seemed doubtful.

Albatrosses are extremely long-lived birds, rarely breeding before they are 10 or 11 years old, and then only producing one chick every other year. Such a slow rate of reproduction is fine for a long-lived species with a low mortality rate, but deaths now exceed replacement which is why the albatrosses are in such trouble. I wish the "Save the Albatross" campaign every success, while I have stopped buying, and eating, tuna..

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Kiwis on the Up

Now for some good news from the Southern Hemisphere. The kiwi, New Zealand's national symbol, is benefiting from a major conservation programme and numbers are rising again for the first time for many years. Estimates suggest that there were once 12 million kiwis in New Zealand (they occur nowhere else) but the current combined population for all three species is a mere 70,000. Few New Zealanders have ever encountered a wild kiwi for these curious birds are both shy and nocturnal and difficult to see unless you go out specifically to look for them.

Kiwis have been protected by law since 1896 but this didn't save whole populations from being wiped out by introduced cats and dogs and other predators. Kiwis evolved some 30 million years ago without any need to protect themselves against predators for New Zealand lacked any mammals until they were introduced by human settlers during the last millennium. In addition, forest destruction worked against the kiwi so in the end just small fragmented populations have survived.

In 1991 the Kiwi Recovery Programme was launched and it is thanks to this that the current increase in numbers has taken place. The programme has concentrated on three techniques: predator control, educating the public in keeping their dogs under control in kiwi areas, and the captive rearing of chicks. Recent surveys show a 10% increase in kiwi numbers and if this growth in numbers continues there is a chance that the kiwi might eventually be removed from the list of endangered birds.

When I visited New Zealand some years ago I succeeded in seeing little spotted kiwis on the island of Kapiti. This small offshore island has a thriving population of this, the rarest of the three kiwis. No one knows for sure where Kapiti's kiwis came from but it is thought they were introduced from the South Island in the 1920s. There's little doubt that if the birds hadn't been moved to Kapiti they would have become extinct. Since (introduced) possums were eradicated from Kapiti in the early 80s, the kiwis have flourished and surplus birds have been successfully introduced to several other predator-free offshore islands.

I was lucky enough to stay overnight on Kapiti and so enjoyed the excitement of a nocturnal kiwi hunt. They are noisy birds so the technique is to follow the bird's calls and snuffles and then fire the torch at it. I enjoyed some excellent views on my first night so on the second night I went out armed also with my camera and flash gun. Ironically, that night I was less successful and the few birds I found all bolted at the sight of my torch beam, so I never did get a photograph.

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A honey buzzard autumn

Late September produced an exceptional number of records of honey buzzards in eastern England, making this the best year ever for honey buzzard in Britain. Almost all the birds seen are likely to have drifted across the North Sea from Scandinavia on freak easterly winds.

Honey buzzards are strongly migratory, returning to their European breeding grounds from tropical Africa in early May, with the autumn passage taking place in September. Huge numbers of honey buzzards can be seen at migration bottlenecks at Gibraltar and southern Spain, and at the Bosphorus in Turkey. Like all big soaring birds, honey buzzards dislike crossing water so they choose the shortest sea crossings possible as they move from Africa and Asia to Europe.

Sweden has one of the highest populations of honey buzzards in Europe with at least 3,000 breeding pairs. In a typical year most of these birds will funnel down through Falsterbo in southern Sweden before migrating on to Africa. A certain number of these birds have been blown off course, hence their unexpected appearance in England.

Honey buzzards are deceptively similar in appearance to the common buzzard though they are not related. With practice (and given a good view) they are easy to tell apart for they soar on flat wings (common buzzards always display a gentle V) while the wing shape is also distinctively different. Their plumage is hugely variable but a typical honey buzzard shows a concentric underwing pattern that the equally variable common buzzard never has.

A small number of honey buzzards nest in Britain but no one is sure how many. The New Atlas of Breeding Birds (1993) suggests that as many as 30 pairs occur each year. More recent estimates put the figure at closer to 100 though there is no firm evidence for this higher number. As their name suggests honey buzzards do feed on honey though the larvae of wasps is by far their most important diet. Wasps do best in hot summers so our small honey buzzard breeding population depends on good weather for a plentiful supply of food. In poor summers, few young are fledged.

For the visiting honey buzzards that reached eastern England their sojourn here was brief with few pausing for more than a day or two before resuming their southerly migration. It would be intriguing to know, however, if these Scandinavian birds continued their passage by travelling on through France and Spain or whether, when they reached the continent, they drifted back on to their usual migration route towards Turkey.