Rise in divers mystifies experts

A red-throated diver pictured on Shetland

The success of a wild bird in Scotland despite declining numbers in the rest of Europe has mystified experts.

RSPB Scotland said it was delighted but puzzled by breeding figures for the red-throated diver.

The rarer black-throated diver is also on the increase, possibly thanks to the anchoring of man-made rafts in lochs.

A survey of divers by the RSPB and Scottish Natural Heritage (SNH) found the two species had increased in the UK by 16 and 34% in the last 12 years.

Both have declined in Europe and the black-throated diver was last week made a conservation priority by the UK government because of the declines elsewhere.

In Scotland, its numbers rose from 187 pairs in 1994 to 217 pairs in 2006.

In the Highlands - their stronghold - they were declining because some nests were being drowned in floods while eggs at other sites were lost to collectors and predators.

We feared the numbers of red-throated divers might drop because the warming of the North Sea seems to be reducing stocks of the fish they feed on Dr Mark Eaton RSPB scientist

The new study shows the greatest increase in the Western Isles, but also improved figures in the Highlands.

A total of 58 rafts have been installed on remote lochs in the region. They protect the birds from flooding and animals that prey on them and their eggs.

Stuart Benn, senior conservation officer for the RSPB, said: "We can't say hand on heart that the overall increase is due to the rafts because we haven't ringed the chicks, but there is no doubt that the rafts have turned out to be very, very good at what they do."

The RSPB said it was a mystery as to why red-throated divers had done so well.

Its numbers have risen from 935 to 1,255 breeding pairs in 12 years.

'Rain goose'

However, in Shetland the population has dropped from 700 pairs to 407.

The red-throated diver is steeped in mythology and is known as the rain goose in Orkney and Shetland.

In the 19th Century, it was regarded as a foreteller of storms in many parts of the world.

Dr Mark Eaton, an RSPB scientist, said: "We feared the numbers of red-throated divers might drop because the warming of the North Sea seems to be reducing stocks of the fish they feed on.

"The black-throated diver could also be at risk in the future, despite the recent increases. If climate change causes loch temperatures to rise, the small fish the birds feed on could grow too large to eat."

City birds sing for silent nights

A Robin (Image: PA)


Urban robins find it too noisy to communicate during daylight
Robins in urban areas are singing at night because it is too noisy during the day, researchers suggest.

Scientists from the University of Sheffield say there is a link between an area's daytime noise levels and the number of birds singing at night.

Until now, light pollution had been blamed because it was thought that street lights tricked the birds into thinking it was still daytime.

The findings are published in the Royal Society journal Biology Letters.

"You generally only seem to hear nocturnal singing in cities," explained Richard Fuller, one of the study's co-authors.

"So this led us to think that there was some aspect of the urban environment that was driving this phenomenon."

Shedding light

Light pollution had been widely held as the prime suspect. It was thought to prevent the birds from roosting, leading to them remaining active through the hours of darkness.


Noise levels were 10 times higher in places where birds were singing at night
Dr Richard Fuller,
University of Sheffield

"That was the stock answer you would get," Dr Fuller said, "that it was basically tricking the birds into thinking it was daylight and tripping some sort of physiological threshold.

"But we thought that was pretty unlikely because birds are much more complex than that."

He said that there had never been a scientific study to measure the impact of light pollution on the behaviour of urban robins.

"So we went out and measured both noctural light and daytime noise levels and we found that daytime noise had a far stronger effect.

"We found that night-time light had a small effect, but very much smaller than the impact of noise levels."

This led the team to conclude that it was an active decision by the birds to sing at night rather than passively responding to light levels.

"The birds appear to be singing at night to avoid competition with high noise levels caused by our cities during the day," Dr Fuller suggested.

"Noise levels were 10 times higher in places where birds were singing at night."

The findings form a part of a seven-year research programme by the university's Department of Animal and Plant Sciences to measure the impact of urbanisation on biodiversity.

Has Russia declared war on birds?

By Tatyana Sinitsyna

RIA Novosti

(MCT)

MOSCOW - Many migratory birds are already heading for their summer homes in Russia. By the eternal laws of nature, birds are flying in large numbers to their nesting-places for the sake of raising a new generation.

Today, however, few people romanticize the spring return of birds because they have been discredited by the rise of avian flu.

Though ornithologists say the "guilt" of birds has not been proven, fears of a new "plague" seem to be overriding common sense. People are ready to declare a real war on wild birds.

As spring arrives, there are more and more calls from various levels of Russian society to exterminate migratory birds. Alexei Zimenko, the director of the Wild Nature Center, describes such a method of preventing avian flu as "shameful, absurd and unacceptable." First, it would pose a serious threat to endangered species. Second, according to Zimenko, the massive shooting of birds would only encourage an epidemic because killed and wounded birds spread the infection. Third, such measures are very expensive: for example, the work of scare-away teams in the Novosibirsk Region alone costs 300 million rubles a year.

Flocks of birds fly mostly at night, and during the day they stop at their customary migratory places, often near water. It is here that they should be targeted, according to the recommendations. In the instructions it sent to all regional committees, the Russian Agency for Health and Consumer Rights underlines: "Take measures to prevent the nesting of migratory birds near reservoirs and at places of possible contact with poultry." The local authorities will decide which methods to use.

The same is recommended in a letter from the Russian Veterinary Supervision Agency to local authorities: "In population centers situated near the shores of reservoirs where migratory birds have nesting-places, organize measures to scare away birds to a distance of 3 to 10 kilometers from the population centers." The letter contains an important piece of advice: "use all acoustic and other methods." The latter is a clear reference to firearms.

"Besides the fact that the shooting of birds is inhumane and anti-environmental, it is also pointless. Birds are very mobile, and there are so many of them that you cannot exterminate them even if you give every Russian a gun," says Yevgeny Kuznetsov, a leading expert at the Center for the Protection of Wild Animals' Health.

He believes that any attempt to scare away, not to mention shoot, wild birds will only force them to search for new places to feed, rest and nest, meaning they will fly to unusual places.

The problem of avian flu is so serious that it has become the focus of attention not only of scientists and experts but political parties as well. The ruling United Russia party has held a conference on the matter. "Avian flu has existed for millions of years. At present, no type of animal flu is dangerous for humans," Professor Yevgeny Voronin, the rector of the Skryabin Moscow Veterinary and Biotechnology Academy, told the conference. "I can drink a medicine bottle of the H5N1 virus and nothing will happen to me. Students at our academy study virology and work with the live avian flu virus. I have never heard that anyone has suffered."

The tone of another speaker, Academician Dmitry Lvov, the director of the Ivanovsky Virology Research Institute, was different. He believes the possibility of a pandemic on all continents is real. According to Lvov, the potential of the H5N1 virus is greater than that of the Spanish influenza that claimed the lives of 50 million people at the beginning of the 20th century. "For the deadly virus to spread from human to human, only two biochemical changes are needed. If this happens, it will be a disaster," he warned.

The scientist added that it was impossible to counter the process of evolution in ecosystems. "It is impossible to prevent a pandemic or an epizootic (an epidemic affecting animals) because it is a disaster like a hurricane or an earthquake. But it is possible and necessary to reduce the possible effects of such disasters through forecasting and prevention," he stressed. Among the obligatory steps to be taken against avian flu, he named the vaccination of household poultry, reliable protection measures to isolate poultry farms, the vaccination of poultry farm personnel, and wide-ranging disinfection measures.

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ABOUT THE WRITER

Tatyana Sinitsyna is a commentator for the Russian News and Information Agency Novosti; Web site: http://en.rian.ru/. The Washington Bureau of RIA Novosti can be reached by phone at (202) 328-3238, fax (202) 328-0137, or e-mail: novosti@comcast.net.

The opinions expressed in this article are those of the author and may not necessarily represent those of RIA Novosti.

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© 2007, RIA Novosti