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  PlanetArk 26 May 06
 Migrant Birds From Africa in Serious Decline - Study
SOUTH AFRICA: May 26, 2006 JOHANNESBURG - Several bird species that make annual migrations between Africa and Europe have experienced drastic population declines and scientists are not exactly sure why, conservationists said on Friday.

The findings were revealed in a study by the Britain-based Royal Society for the Protection of Birds (RSPB) and BirdLife International.

"Scientists fear that their dwindling numbers -- well over 50 per cent down in some cases -- may be a warning of widespread environmental damage, which could soon affect man as well," the RSPB said in a statement. "Climate change, drought and desertification in Africa, and massive pesticide use on African farmland may all be to blame for the declines of once common UK birds such as the spotted flycatcher, wheatear, wood warbler and turtle dove," it said.

Researchers were looking at factors such as drought and heavy pesticide use in the Sahel region of Africa, which borders the Sahara desert and is a major stopover point for birds that have made the exhausting journey across the unforgiving sands.

The RSPB said the research, to be published in the journal "Biological Conservation", showed that 54 percent of the 121 long-distance migrants studied have declined or become extinct in many parts of Europe since 1970.

The RSPB said species such as the red-backed shrike no longer breed in Britain, while the spotted flycatcher's numbers were down 86 percent in the United Kingdom. "These migrants are highly evolved and some range over a quarter of the planet's land surface. For species like this to be affected so severely suggests that something pretty serious is going wrong somewhere," said the RSPB's Dr Paul Donald, a co-author of the study.

BBC 25 May 06
Migrating birds suffer huge loss
By Rebecca Morelle BBC News science reporter

Migratory birds have suffered a dramatic decline in numbers, according to a study.

Species that migrate thousands of miles from Africa to the UK have been the worst hit over the last 30 years.

The researchers say the cause of the decline remains a "mystery", but could be linked to climate change, habitat destruction or pesticide use.

Writing in the journal Biological Conservation, they warn the losses may indicate wider environmental damage. The Royal Society for the Protection of Birds (RSPB) and BirdLife International study analysed population trends of European breeding birds, including non-migratory birds and those that migrate both short and long distances.

The data spanned three decades, from 1970 to 2000.

"We found that long distant migrants - the ones that go right across the Sahara, like the swallows, flycatchers and warblers - have shown a fairly consistent pattern of decline," said Dr Paul Donald, an author on the paper from the RSPB.

Those that winter in Africa, he said, seem to be the most affected.

The study also compared the long-distant migratory birds with closely related non-migratory birds, but again found in almost every case that the migratory birds faired worse. Fifty-four percent of the 121 long-distant migratory birds studied suffered plummeting numbers or had even become extinct since 1970.

The roll-call of declining species is long.

"Some fairly iconic species have declined enormously in Europe. There is a very beautiful blue and purple bird called the roller - the population of that bird is crashing all over Eastern Europe," Dr Donald told the BBC News website.

"In the UK, other species that have declined enormously are spotted flycatchers, pied flycatchers, wheatears, wood warblers and tree pipits."

Changing climate

The exact reason for the birds' decline, according to the authors, is a "mystery".

But several theories to explain the losses have been put forward, and will now be investigated.

One explanation is tied to the changing conditions in Africa, where the birds winter. "We know that agriculture has spread; we know there has been a long-term drought in the Sahel; and we know huge amounts of pesticides are used to control locust outbreaks," said Dr Donald.

The swelling size of the Sahara may also be hampering the birds. Migrating birds face longer and longer non-stop flights across the desert.

Climate change has been highlighted as a potential culprit. Warmer springs in Europe are causing some insects to hatch earlier in the year, which means by the time the migratory birds arrive to breed and raise their young they may have missed their much-needed food-source.

"Migrants make up a high proportion of our species of birds, so this is a big conservation issue," said Dr Donald. "But if you think that these are birds that cover vast areas of the Earth's land-surface - this consistent pattern of decline is indicative that there are some pretty severe environmental changes going on somewhere which might also have an impact on humans."

The authors conclude that urgent action is needed to uncover the cause of the decline. "There is something about being a migrant that counts against them," said Dr Donald. "These birds have been slipping away from under our noses for 30 years, and we've never has really noticed it before."
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