Climate change raising extinction risk among birds: study

Yahoo News 19 May 08;

Climate change has emerged as a major factor behind the growing risk of extinction facing birds, the world's leading conservation agency warned on Monday.

"Long-term drought and sudden extreme weather are putting additional stress on the pockets of habitat that many threatened species depend on," the International Union for Conservation of Nature (IUCN) said in a report issued on the sidelines of a global biodiversity convention.

"This, coupled with extensive and expanding habitat destruction, has led to an increase in the rate of extinction on continents and away from islands, where most historical extinction has occurred."

The Swiss-based organisation issued an update of its "Red List," the highly respected catalogue of species at threat.

Of the 1,226 birds on the list, 190 are "critically endangered," the highest category of threat.

Eight additional species have entered this category compared to the last list. These each face an extremely high risk of extinction in the wild, and include the Tristan albatross (Diomedea dabbenena) of the South Atlantic and the Floreana mockingbird (Nesomimus trifasciatus) of the Galapagos islands.

In all, 24 species have moved into a higher level of threat as a result of shrinking population or declining habitat. Just two species have seen their prospects improved.

Those seen at greater threat include widespread continental species such as the Eurasian curlew (Numenius arquata) and Dartford warbler (Sylvia undata), both previously in the "least concern" category but now regarded as "near threatened."

"Species are being hit by the double whammy of habitat loss and climate change," said Stuart Butchart, research coordinator with BirdLife, an alliance of conservation organisations, which helped compile the list.

"As populations become fragmented the effect of climate change can have an even greater impact, leading to an increased risk of local extinctions."

The IUCN highlighted the threat to three species:

-- The Mallee emuwren (Stipiturus mallee), a native of South Australia, where the last significant population comprises just 100 birds confined to 100 square kilometres (38 square miles). "Its habitat is now so fragmented that a single bushfire could be catastrophic," the IUCN warned;

-- The New Britain Goshawk (Accipiter princes), a bird of prey in Papua New Guinea, whose habitat has been ravaged by palm-oil plantations;

-- The spoon-billed sandpiper (Eurynorhynchus pygmeus), which migrates between northeastern Russia and Southeast Asia. Its tidal-flat habitat has been badly eroded and its tundra breeding grounds are threatened by climate change.

The rare pieces of good news offered by the IUCN were attributed to two successful conservation programmes.

The first involved the Marquesan Imperial-pigeon (Ducula galeata), whose signature call is a "deep bellow waah-waah, like the mooing of a cow," according to BirdLife.

The species, which is a native of French Polynesia, is doing well under a translocation programme which has shifted breeding pairs to a new home.

The other is the little spotted kiwi (Apteryx owenii). Individuals have been moved out of New Zealand's South Island to new territories and are slowly reproducing.

"This goes to show not only that conservation action works but that it is vital if we are to prevent the extinction of these and other species," Butchart said.

Some 6,000 representatives from 191 countries are attending the 11-day conference on the UN's convention on biodiversity, which was first adopted at the Rio Earth summit in 1992.

Climate change hitting bird species, shows study
Madeline Chambers, Reuters 19 May 08;

BONN, Germany (Reuters) - One in eight of the world's birds are at risk of extinction as climate change puts birds under great pressure, a leading conservation group warned on Monday.

The population of rare birds such as the Floreana mockingbird of the Galapagos Islands or the spoon-billed sandpiper, which breeds in northeastern Russia and winters in south Asia, has declined sharply and they could go extinct, the International Union for Conservation of Nature said in a report.

The 2008 "Red List for Birds" report, published on the first day of a May 19-30 U.N. conference about biodiversity in the German city of Bonn, said 1,226 species of bird were now threatened.

The annual report, closely watched among conservationists, added eight of the world's 10,000 bird species to the Critically Endangered category, the greatest level of threat.

"The latest update of the IUCN Red List shows that birds are under enormous pressure from climate change," said Jane Smart, head of the IUCN Species Programme. The IUCN groups governments, conservation groups and scientists.

Long-term drought and sudden extreme weather are putting additional stress on habitats that threatened species depend on, said the report, noting that extinction rates were rising on continents, rather than on islands where, historically, most extinctions have occurred.

Of the 26 species that moved category due to changes in their population size, rate of decline or range size, 24 were moved up to a higher level of threat.

CURLEW, WARBLER

They included the Eurasian curlew and Dartford warbler, which lives in Europe and north-west Africa. Both were previously in the "Least Threatened" category.

"We urge governments to take the information contained in (the report) seriously and do their level best to protect the world's birds," said Smart. The U.N. Climate Panel says that burning of fossil fuels is stoking global warming.

The report showed that Brazil and Indonesia had the highest number of threatened bird species with 141 and 133 respectively.

The group picked out several other species, including the Mallee emuwren in Australia which has suffered from years of drought and is seeing its population shrink sharply.

Its habitat has become so fragmented that a single bushfire could be catastrophic, said the report.

In the Galapagos Islands, the population of the Floreana mockingbird has fallen to fewer than 60 from an estimated 150 in 1996 and is now on the Critically Endangered list because the species is vulnerable to extreme weather.

The report also pointed to some species that had fared better as a result of conservation efforts, including the Marquesan Imperial-pigeon and the little spotted kiwi.

Around 4,000 delegates at the U.N. meeting of the Convention on Biodiversity will discuss ways to safeguard the range of species and try to slow the rate of extinctions among plants and animals.

(Editing by Ibon Villelabeitia)

Climate 'accelerating bird loss'
Mark Kinver, BBC News 19 May 08;

Climate change is "significantly amplifying" the threats facing the world's bird populations, a global assessment has concluded.

The 2008 Bird Red List warns that long-term droughts and extreme weather puts additional stress on key habitats.

The assessment lists 1,226 species as threatened with extinction - one-in-eight of all bird species.

The list, reviewed every four years, is compiled by conservation charity BirdLife International.

"It is very hard to precisely attribute particular changes in specific species to climate change," said Stuart Butchart, BirdLife's global research and indicators co-ordinator.

"But there is now a whole suite of species that are clearly becoming threatened by extreme weather events and droughts."

In the revised Red List, eight species have been added to the "critically endangered" category.

One of these was the Floreana mockingbird ( Nesomimus trifasciatus ), which is confined to two islets in the Galapagos Islands.

From an estimated maximum of 150 in the mid-1960s, the population has fallen to fewer than 60.

Conservationists listed the mockingbird as Critically Endangered because it experienced a high rate of adult mortality during dry years that have been linked to La Nina events.

Dry years have become more frequent in recent years, and have been blamed as the main driver of the current decline.

"Another threat for small island species, such as the Floreana mockingbird, is the threat from invasive species, in particular mammals and plants," Dr Butchart told BBC News.

"They are having a devastating effect on habitats. For example, goats and donkeys on Floreana are changing the ecological structure.

"Eliminating or controlling invasive species is a very tractable conservation action that can help these birds hang on in the face of these additional pressures from climate change.

"The key actions that are needed to prevent a species like this from going extinct are the very broad-scale climate-change mitigation measures - such as reducing our carbon emissions, limiting the global average temperature rise to no more than 2C (3.6F), and changing society's values and lifestyles."

Dr Butchart said another example of a species being affected by shifts in the climate was the akekee ( Loxops caeruleirostris ), a Hawaiian honey-creeper.

"Not only is it being negatively impacted by prolonged heavy rain causing nesting failures, but they are extremely threatened by introduced diseases, which are carried by invasive mosquitoes.

"The mosquitoes have been restricted to lower altitudes, so the birds do best at heights above which the mosquitoes can go and pass on avian malaria.

"But because of climate change, the temperature zones are shifting. It is getting warmer at higher altitudes, so the mosquitoes can now move higher.

"This is eliminating the mosquito-free zone that the birds used to occupy."

As a result, Dr Butchart explained, this bird was also being uplisted to the status of Critically Endangered.

Despite the latest assessment showing a continuing downward trend in the world's bird populations, he said that conservationists were still optimistic that many species could be saved.

"It is undoubtedly true that we are facing an unprecedented conservation crisis but we do have conservation success stories that give us hope that not all threatened species are doomed.

"We have the solutions but what we need are the resources and political will."

BirdLife International has recently launched its Preventing Extinctions Programme, which targets the 190 species listed as Critically Endangered.

Its goal is to find a "species champion" for each bird, who will fund the on-the-ground conservation work of "species guardians".

"Success stories provide us with the great hope that this can be achieved, provided that we act soon enough."

One bird that has been downlisted from Critically Endangered to Endangered in the latest assessment is the Marquesan imperial-pigeon ( Ducula galeata ).

The main threat facing the bird came from rats, an invasive species.

In order to protect the population of the slow-breeding birds, conservationists moved 10 adults to a neighbouring rat-free island between 2000 and 2003.

The new community of pigeons is now established on the island, and conservationists are hopeful that the population will reach 50 by 2010.

"This has greatly reduced the extinction risk because the bird is now spread over a couple of islands," observed Dr Butchart.

"This goes to show not only that conservation works but that it is vital if we are to prevent the extinction of these and other species."