Invasive species lie in wait, strike after decades

Animals and plants introduced from foreign habitats may not reveal themselves to be harmful 'invasive' species for decades, according to a European study published on Monday. (Left: Canadian geese)

Species that are moved away from their natural predators back home can displace native species in their new habitats, and scientists say the problem already costs Europe 12 billion euros ($16 billion) a year.

The study, which is likely to hold true for other continents too, means that the seeds of future, perhaps bigger, problems have literally already been sown.

The study compared the effects of "alien species" such as American ragweed,(right) Canada geese (see above left) or Japanese deer in 28 European countries.

The study's findings indicated that it can take decades to figure out which alien species will be disruptive, and looking at those that arrived in 1900 was a better indicator of current problems than looking at those from 2000.

"This lag in the cause-and-effect relationship would mean that ... the seeds of future invasion problems have already been sown," said the study, published in the U.S. Proceedings of the National Academy of Sciences. (Left: Canadian thistle)

Birds and insects were quickest to get established in new habitats, helped by their mobility. Others took far longer to reach the critical numbers to become invasive.

Introductions to Europe from the 19th century included ragweed, whose pollen is blamed for some hay fever, and the black locust tree (right), also from North America, which can damage European grassland with its ability to store nitrogen.

Increasing trade and travel during the 20th and 21st centuries means that the problems are likely to worsen unless checks on everything from the ballast tanks of ships to coffee or grain imports are tightened.

"We should do more about this problem now," said Stefan Dullinger, of the University of Vienna, Austria, who was among authors of the study from institutes in New Zealand, the Czech Republic, Germany, Switzerland, Spain, Italy and France. (Left: Florida parakeets)

"Otherwise, things can become even much worse than they are in a few decades," he said. The findings for Europe were likely to be mirrored elsewhere in the world. (Right: Kudzu in the south of the US - grows so fast people say they can see it happening)

The study also recommended that Europe should target controls at animal and plant species that were so far causing no damage but were known to be invasive in other habitats. (Left: map of distribution of invasive species)

Climate change could also add to the spread. "Warmer temperatures could trigger the spread of invasive species that are limited by climate now," Dullinger said.

Source:
Reuters, "Invasive species lie in wait, strike after decades", accessed December 22, 2010

Genetic breakthrough in fight against honeybee killer

A breakthrough in the battle against a deadly mite responsible for decimating the honeybee population has been welcomed by conservation groups.

The varroa mite is the biggest killer of honeybees and has become resistant to medication developed to destroy it. But now scientists have identified a genetic technique that could stop the mite in its tracks.

Researchers from the government's National Bee Unit and Aberdeen University have worked out how to "silence" natural functions in the mites' genes.

Alan Bowman, from the University of Aberdeen, said: "Introducing harmless genetic material encourages the mites' own immune response to prevent their genes from expressing natural functions. This could make them self-destruct.

"This approach targets the mites without harming the bees or, indeed, any other animal."

Giles Budge, from National Bee Unit, part of the Food and Environment Research Agency (Fera), agreed. "This cutting-edge treatment poses no threat to the bees.

"With appropriate support from industry and a rigorous approval process, chemical-free medicines could be available in five to 10 years."

The mite, which looks like a tiny brown crab, hitches a ride on the bee, draining its blood and weakening its immune system. It takes just 1,000 mites to kill a colony of 50,000 bees.

Honeybees play a vital role in food production as crop pollinators but populations fell between 10 and 15% in the two years to 2009.

The mite is particularly deadly during the winter months as it strikes when bee numbers are depleted and colonies do not have enough bees to keep warm.

The mite originally attacked the Asian honeybee but jumped to the European honeybee, which has a poor natural defense. It injects viruses, suppresses the bees' immune system and feeds on blood. Beekeepers use chemical controls but can never eradicate it and over the past decade the varroa developed resistance to some medication. (At right: distribution of varroa mite in red)

The environment minister Lord Henley said: "Bees are essential to putting food on our table and worth £200m to Britain every year through pollinating our crops.

"This excellent work by UK scientists will keep our hives healthy and bees buzzing."

The process uses the Nobel Prize-winning theory "RNA interference", which controls the flow of genetic information. So far the "silencing" has worked with a neutral varroa gene, which has no significant effect on the mite.

Scientists now need to target a gene with the specific characteristics that are perfect to force the varroa to self-destruct. Tests by other scientists have shown the treatment can be added to hives in bee feed. The bees move it into food for their young, where the varroa hides.

Martin Smith, president of the British Beekeepers Association, said: "While this research is at the early stage, we are pleased that work is being undertaken to try and control the varroa mite which remains the largest threat to beekeeping in this country. We look forward to seeing further work in this area."

Source:
The Guardian,"Genetic breakthrough in fight against honeybee killer", accessed December 22, 2010

Beat winter blues with birdsong, National Trust urges

Birdsong can conquer the gloom of shorter winter days, says the trust as it launches an online audio guide to Britain's best-loved species.

The National Trust is urging people to tune into birdsong to help conquer the gloom of the short winter days of the year.

The trust has recorded birds at Woodchester Park in Gloucestershire and created an online audio guide to some of Britain's best-loved species, from favorites such as the robin and members of the tit family to the blackcap (right) and great-crested grebe. Others contributing to the soundtrack include the goldcrest, blackbird, thrush, chiffchaff, wren, mallard, coot and even the garden bully, the wood pigeon (below left).

Whether the song is to ward off competitors for territory or seeking a mate, trust ecologist Peter Brash insists listeners will feel better for hearing it. "We're all attuned to the need to eat five fruit and vegetables a day or take a 30-minute walk. Taking the time out to listen to five minutes of birdsong every day could be beneficial to our wellbeing."

"Even today, when we have less than eight hours of daylight, there will be plenty of birds around to lift the spirits," said Brash. "Though there is no real substitute for listening to birds sing in the outdoors and we're never that far away from birdsong wherever we are." (At right: chiffchaff bird)

Source:
The Guardian,"Beat winter blues with birdsong, National Trust urges", accessed December 22, 2010

Africa Has Two Elephant Species, Genetic Analysis Confirms

Contrary to the belief of many scientists (as well as many members of the public), new research confirms that Africa has two -- not one -- species of elephant. Scientists from Harvard Medical School, the University of Illinois, and the University of York in the United Kingdom used genetic analysis to prove that the African savanna elephant (left) and the smaller African forest elephant have been largely separated for several million years.

The researchers, whose findings appear online in PLoS Biology, compared the DNA of modern elephants from Africa and Asia to DNA that they extracted from two extinct species: the woolly mammoth and the mastodon. Not only is this the first time that anyone has generated sequences for the mastodon nuclear genome, but it is also the first time that the Asian elephant, African forest elephant (right), African savanna elephant, the extinct woolly mammoth, and the extinct American mastodon have been looked at together.

"Experimentally, we had a major challenge to extract DNA sequences from two fossils -- mammoths and mastodons (left) -- and line them up with DNA from modern elephants over hundreds of sections of the genome," says research scientist Nadin Rohland of the Department of Genetics at Harvard Medical School.

According to David Reich, associate professor in the same department, "The surprising finding is that forest and savanna elephants from Africa -- which some have argued are the same species -- are as distinct from each other as Asian elephants and mammoths."

Researchers only had DNA from a single elephant in each species, but had collected enough data from each genome to traverse millions of years of evolution to the time when elephants first diverged from each other.

"The divergence of the two species took place around the time of the divergence of the Asian elephant and woolly mammoths," says Professor Michi Hofreiter, who specializes in the study of ancient DNA in the Department of Biology at York. "The split between African savanna and forest elephants is almost as old as the split between humans and chimpanzees. This result amazed us all."

The possibility that the two might be separate species was first raised in 2001, but this is the most compelling scientific evidence so far that they are indeed distinct.

Previously, many naturalists believed that African savanna elephants and African forest elephants were two populations of the same species, despite the significant size differences. The savanna elephant has an average shoulder height of 3.5 meters whereas the forest elephant has an average shoulder height of 2.5 meters. The savanna elephant weighs between six and seven tons, roughly double the weight of the forest elephant. (Left: range of African elephants)

African savannah elephants are found in savannah zones in 37 countries south of the Sahara Desert. African forest elephants inhabit the dense rain forests of west and central Africa. The continent’s northernmost elephants are found in Mali’s Sahel desert. The small, nomadic herd of Mali elephants migrates in a circular route through the desert in search of water.

DNA analysis revealed a wide range of genetic diversity within each species. The savanna elephant and woolly mammoth have very low genetic diversity, Asian elephants have medium diversity, and forest elephants have very high diversity. Researchers believe that this is due to varying levels of reproductive competition among males.

"We now have to treat the forest and savanna elephants as two different units for conservation purposes," says Alfred Roca, assistant professor in the Department of Animal Sciences at the University of Illinois. "Since 1950, all African elephants have been conserved as one species. Now that we know the forest and savanna elephants are two very distinctive animals, the forest elephant should become a bigger priority for conservation purposes."

This research was funded by the Max Planck Society and by a Burroughs Wellcome Career Development Award in Biomedical Science.

Source:
Science News, "Africa Has Two Elephant Species, Genetic Analysis Confirms", accessed December 22, 2010
Journal Citation:
Nadin Rohland, David Reich, Swapan Mallick, Matthias Meyer, Richard E Green, Nicholas J Georgiadis, Alfred L Roca, Michael Hofreiter. Genomic DNA Sequences from Mastodon and Woolly Mammoth Reveal Deep Speciation of Forest and Savanna Elephants. PLoS Biology, 2010; 8 (12): e1000564 DOI: 10.1371/journal.pbio.1000564

Forests size of Russia 'could be restored'

Forests covering an area almost the size of Russia could be restored around the world, according to a global partnership of scientists.

The researchers, including the International Union for Conservation of Nature (IUCN), have drawn up a world map showing 1.5 billion hectares where there are opportunities to replant degraded or cleared forests.

Carole Saint-Laurent, IUCN's senior forest policy advisor, said: "There's no one-size-fits-all blueprint. The restoration would need to be driven by the community needs in each area.

"We know it can be done. There are people all over the world who are doing it already."

Three quarters of the world's forests have been cleared, degraded or fragmented due to human activity, while a third have disappeared altogether, according to IUCN.

However, as forests fulfill needs for food, fuel and timber, restoring them can benefit communities as well as the environment, the organization said.

The map was drawn up by the World Resources Institute, South Dakota University and IUCN, for the Global Partnership on Forest Landscape Restoration ahead of the launch of the United Nations International Year of Forests 2011.

Saint-Laurent said: "This study came out of a partnership with about 30 governments all over the world. We are bringing people who are working on forest restoration together, as well as increasing understanding of the contribution that forest landscape restoration can make in addressing climate change.

Saint-Laurent added: "So far this is all at a global level, but our next step is to apply this to individual countries to give a more detailed picture."

The map was created using information on areas that were once forest and have the potential to be re-grown, according to Saint-Laurent. The researchers excluded areas that are now urban or crop land.
However, they still need to look in more detail to determine exactly where it is feasible to re-grow forest.

"These are 1.5 billion hectares where opportunities could be found," said Saint-Laurent. "More analysis needs to be carried out to find what's really possible within that, because we haven't been able to map land rights, and there might be areas that are not suitable from a social point of view.

"Even if you took out a third, it's still a vast area and a vast opportunity."

Often, this would be done in small patches between farms or villages, or along corridors to protect waterways or fields.

"We are talking about taking landscapes that are not doing anything for anybody and producing something of value," said Saint-Laurent.

"It can help create livelihoods for communities. There's an increasing groundswell of interest at the moment in forest restoration. People are starting to see there's a wonderful opportunity that forests can offer more to people than they already do. For example, in an area of Tanzania over a 15-year period significant areas of forest have been restored in small patches around villages and farms. It means the women do not need to walk as far to get their firewood for fuel, which has significant benefits for families."

"You are accommodating a diversity of land uses in one area."

IUCN said the greatest opportunities for restoring forests were in Africa and Asia, each offering potential for 500 million hectares. In the African countryside for example, many tree species can be planted to improve living conditions in the short and the long term. Fruit trees (mango) that over time will offer a varied diet and additional income, have fast growing branches that need to be cut back. These branches are perfect for firewood and are useful as construction materials to build homes and protective fences for fields and animals.

The emphasis on restoring forests would complement work on preventing deforestation in the first place.

"This is not a replacement for protecting native primary forests, but it's an add-on," said Saint-Laurent. "We need to protect forests, but also put something back where they have been degraded. Over a 30-year-period we believe this could have as much benefit as avoided deforestation."

The U.N.'s International Year of Forests 2011 will be launched to take over from International Year of Biodiversity 2010 on December 18.

Source:
Cable Network News (CNN), "Forests size of Russia 'could be restored'", accessed December 22, 2010

That snow outside is what global warming looks like

Unusually cold winters may make you think scientists have got it all wrong. But the data reveal a chilling truth. There is now strong evidence to suggest that the unusually cold winters of the last two years in the UK are the result of heating elsewhere.

With temperatures in some parts of the UK and Ireland set to reach as low as 28°C on Monday night, many have been wondering why this winter has been especially harsh. According to NASA the reason is a natural shift the the location of the Gulf Stream called ‘Negative Arctic Oscillation’.

Writing on their Earth Observatory site NASA describes how the Gulf Stream, which usually bring mild air from the Mexican Gulf to the British Isles, has shifted from its usual path due to a belt of high pressure sitting in the mid-Atlantic. This oscillation has forced the stream further north bathing western Canada and southern Greenland in unusually warm weather while leaving Ireland, the UK and Northern Europe freezing cold.

The Arctic Oscillation is a climate pattern that influences winter weather in the northern hemisphere. It describes the relationship between high pressure in the mid-latitudes and low pressure over the Arctic. When the pressure systems are weak, the difference between them is small, and air from the Arctic flows south, while warmer air seeps north. This is referred to as a negative Arctic Oscillation. Like December 2009, the Arctic Oscillation was negative in early December 2010. Cold air from the Arctic channeled south around a blocking system over Greenland, while Greenland and northern Canada heated up.

The unusual cold brought heavy snow to Northern Europe, stopping flights and trains (right) early in December. Cold temperatures and snow also closed roads and schools in the eastern United States and Canada during the first week of December. The diagonal path of a powerful winter storm is visible as a streak of cold across the Upper Midwest of the United States.

The global temperature maps published by NASA present a striking picture. Last month's shows a deep blue splodge over Iceland, Spitsbergen, Scandanavia and the UK, and another over the western US and the eastern Pacific. Temperatures in these regions were between 0.5C and 4C colder than the November average from 1951 and 1980. But on either side of these cool blue pools are raging fires of orange, red and maroon: the temperatures in western Greenland, northern Canada and Siberia were between 2C and 10C higher than usual. NASA's Arctic oscillations map for 3-10 December (left) shows that parts of Baffin Island and central Greenland were 15C warmer than the average for 2002-9. There was a similar pattern last winter. These anomalies appear to be connected.

The weather in UK winters, for example, is strongly linked to the

The North Atlantic Oscillation also was in a negative phase: i.e. above-normal pressure over Iceland; below-normal pressure over the Azores; in Northern Europe this is usually associated with below-normal temperatures.

contrasting pressure between the Icelandic low and the Azores high. When there's a big pressure difference the winds come in from the south-west, bringing mild damp weather from the Atlantic. When there's a smaller gradient, air is often able to flow down from the Arctic. High pressure in the icy north last winter, according to the US National Oceanic and Atmospheric Administration, blocked the usual pattern and "allowed cold air from the Arctic to penetrate all the way into Europe, eastern China, and Washington DC". NASA reports that the same thing is happening this winter.

Sea ice in the Arctic has two main effects on the weather. Because it's white, it bounces back heat from the sun, preventing it from entering the sea. It also creates a barrier between the water and the atmosphere, reducing the amount of heat that escapes from the sea into the air. In the autumns of 2009 and 2010 the coverage of Arctic sea ice was much lower than the long-term average: the second smallest, last month, of any recorded November. The open sea, being darker, absorbed more heat from the sun in the warmer, light months. As it remained clear for longer than usual it also bled more heat into the Arctic atmosphere. This caused higher air pressures, reducing the gradient between the Iceland low and the Azores high.

So why wasn't this predicted by climate scientists? Actually it was. Obsessed by possible changes to ocean circulation (the Gulf Stream grinding to a halt), we overlooked the effects on atmospheric circulation. A link between summer sea ice in the Arctic and winter temperatures in the northern hemisphere was first proposed in 1914. Close mapping of the relationship dates back to 1990, and has been strengthened by detailed modeling since 2006.

Will this become the pattern? It's not yet clear. Vladimir Petoukhov of the Potsdam Institute says that the effects of shrinking sea ice "could triple the probability of cold winter extremes in Europe and northern Asia". James Hansen of NASA (right) counters that seven of the last 10 European winters were warmer than average. There are plenty of other variables: we can't predict the depth of British winters solely by the extent of sea ice.

Climate change skeptics voice howls of execration at this theory: now you're claiming that this cooling is the result of warming! Well, yes, it could be. A global warming trend doesn't mean that every region becomes warmer every month. That's what averages are for: they put local events in context. The denial of man-made climate change mutated first into a denial of science in general and then into a denial of basic arithmetic. If it's snowing in Britain, a thousand websites and quite a few newspapers tell us, the planet can't be warming.

According to NASA's datasets, the world has just experienced the warmest January to November period since the global record began, 131 years ago; 2010 looks likely to be either the hottest or the equal hottest year. This November was the warmest on record.

Still global warming skeptics say to just look out of the window. No explanation of the numbers, no description of the North Atlantic oscillation or the Arctic dipole, no reminder of current temperatures in other parts of the world, can compete with the observation that there's a foot of snow outside. We are simple, earthy creatures, governed by our senses. What we see and taste and feel overrides analysis. The cold has reason in a deathly grip.

Source:
The Guardian, "That snow outside is what global warming looks like", by George Monbiot, accessed December 22, 2010
The Sociable, "NASA explains why there has been so much snow this winter", accessed December 22, 2010

Polar bear status pits environmentalists vs. administration

A long simmering dispute about how much the government should protect polar bears has turned into a battleground for environmentalists and some of the country's most powerful business organizations over the larger question of global warming. Both sides are concerned about the effect that a decision on the bear's status might have on the regulation of greenhouse gas emissions, which scientists say is driving climate change.

U.S. District Court Judge Emmet Sullivan sent the controversial listing decision back to the Obama administration in October, asking officials to clarify the language the agency used when it determined that polar bears aren’t “endangered” under federal law. The deadline for the official response was this week.

Environmental groups normally friendly to the Obama administration have sued Interior to list the bear as endangered, saying the sea ice the bears need for hunting and breeding is being rapidly depleted by warming temperatures.

If the Obama administration listed the polar bear as endangered, it would have to move against factors that endanger it -- large emitters of greenhouse gases. That possibility worries industries dependent on fossil fuels, such as major manufacturers and utilities.

On Wednesday, the Interior Department filed arguments in federal court defending its decision to classify polar bears as "threatened" rather than "endangered" despite widespread shrinkage of the sea ice that forms the bears' natural habitat.

"The Service explained how its biologists had concluded in 2008 that the polar bear was not facing sudden and catastrophic threats [and] was still a widespread species that had not been restricted to a critically small range or critically low numbers," the agency said in a statement. (Right: polar bear distribution)

What makes the issue so sensitive is that, if polar bears received the stricter endangered classification, the Obama administration would be pressured to attack the problem at its source: the petroleum, coal and manufacturing companies that emit the greenhouse gases scientists say are a major factor in climate change.

"There is a pronounced push-back from industry because they rightly see that they will have to modify or mitigate their activities to comply with the laws," said Andrew Wetzler, director of the Land and Wildlife program at the Natural Resources Defense Council, one of the environmental groups suing to change the polar bear's status.

In early 2009, the Obama administration pledged to revisit several controversial environmental decisions made under George W. Bush — including the polar bear's status. But months later, Obama's Interior Department ratified the bears' "threatened" classification. (Right: sea ice extent)

Listing the polar bear as “endangered” as a result of global warming could open the door to using the Endangered Species Act to regulate greenhouse gases, an outcome the Obama administration has opposed.

Although the Obama administration has moved steadily to reduce greenhouse gas emissions — with a tough reelection campaign ahead in 2012 and a still-wobbly economy — the White House has been trying not to provoke policy battles with the wary business community.

The issue is even more sensitive because tougher emissions rules would be likely to raise prices and could cost jobs.

Scientific data point to a mounting threat to the polar bear, the largest carnivore on land. Polar bears depend on sea ice for hunting, breeding and denning. Typically, polar bears hunt for ringed seals on the sea ice, catching them when they come up for air. However, since the ice is melting earlier and earlier in the year (sea ice melting graph), polar bears are shifting there habitat to land and water, and may be missing out on hunting opportunities

Higher temperatures have brought about a rapid decline in summer sea ice, robbing bears of their hunting platforms. The loss of sea ice essentially threatens bears with starvation.

Despite the scientific evidence pointing to the probable extinction of polar bears in the wild, the Obama administration reaffirmed Wednesday its decision to designate polar bears as a "threatened," not "endangered," species, in defiance of the wishes of conservationists who say the bears are in danger of extinction because their arctic hunting grounds are melting.

The International Union for Conservation of Nature considers the species "decreasing." A recent paper in the journal Ecology concluded there was a "high probability" that polar bears would disappear in the Beaufort Sea, which is off Alaska, by the end of the century.

The Interior Department does not dispute the science, which it uses as the basis of its "threatened" listing. But the listing contains the so-called "4d" exemption, excluding greenhouse gases from being regulated as a threat to a species.

Except for the "4d" exemption, threatened species receive most of the same regulatory protections as those listed under the Endangered Species Act, including a requirement that federal agencies refrain from actions that might jeopardize their existence or destroy or harm their habitat.

Industry groups, including the American Petroleum Institute, the U.S. Chamber of Commerce and the National Mining Assn., are fighting to keep the exemption and to keep the polar bear from being classified as endangered.

Industry leaders said they would be watching the polar bear decision closely as a signal of the administration’s commitment to compromise with them.

"It's based upon the position that the science doesn't exist to draw a link between a particular activity, industrial or otherwise, and an identifiable incremental effect on sea ice," said Richard Ranger, senior policy advisor for API.

"Given the inability to establish a causal relationship between, say, expansion of the port of Los Angeles to sea-ice loss, why should U.S. industries be subject to additional burdens when Chinese industries are not subject to anything?" he said.

A change from threatened to endangered status “would have profound consequences,” said Richard Ranger, senior policy advisor for the American Petroleum Institute, a lead litigant on the industry side. “It would very much get our attention.”

But lawyers for the environmental groups would like to win endangered status for the polar bear precisely because the listing would eliminate the 4d exemption.

Kassie Siegel, director of the Climate Law Institute at the Center for Biological Diversity, called the administration's decision "a huge disappointment." Arctic ice, the bears' hunting ground, is melting and bears are starving to death, she said.

"It's a wasted opportunity to do the right thing," Siegel said. "The government's own studies show about an 80 percent chance of extinction of two-thirds of the world's polar bears in the next 40 years."

Siegel, the lead attorney in the environmental groups' petition to change the bear's status, denounced the government's action and said her group would mount a new legal challenge.

"The new decision from the Obama administration amounts to nothing more than lipstick on a pig," she said. "It puts a gloss on a horribly flawed Bush-era decision that is anti-science and serves to greatly undermine the protection of not just the polar bear but all of America's imperiled wildlife."

Still, some independent legal and scientific experts say the Endangered Species Act may not be an appropriate tool to deal with the impact of climate change, designed, as it was, to regulate humans encroaching on forests or polluting rivers.

"It just screams for some kind of response from Congress and not the courts," said J.B. Ruhl, law professor at Florida State University College of Law and a specialist in endangered species protection. "But in Congress you have a stalemate."

Source:
Los Angeles Times, "Polar bear status pits environmentalists vs. administration", accessed December 23, 2010
Los Angeles Times, "Obama decision on polar bear status closely watched", accessed December 23, 2010
Politico, "W.H.: Polar bears not 'endangered'", accessed December 23, 2010
Washington Post, "Polar bears' 'threatened' designation irks activists", accessed December 23, 2010