Category Archives: Green Alerts

Polar bears eating goose eggs for survival

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Polar bears

may be turning to snow goose eggs to help them survive as Arctic sea ice melts due to global warming, scientists say. Polar bears typically hunt seals out at sea, returning to land when springtime temperatures melt the ice floes the bears use as rest stops. But climate change has been causing sea ice to melt earlier each year, forcing polar bears to come ashore sooner.

In a previous study, biologist Robert Rockwell and his colleague Linda Gormezano documented polar bears in Canada’s Hudson Bay area returning to land about two weeks earlier than they’d done in the past, near the end of June instead of the middle of July. This early arrival brings the bears back to shore around the same time that nesting snow geese are incubating their eggs in Hudson Bay.

Snow goose eggs are more often food for skuas and Arctic foxes. But

polar bears

are famous for their voracious appetites. One polar bear reportedly went on a “goose egg-fest,” Rockwell said, devouring more than 800 eggs in four days. Accounts like this have caused some scientists to worry that hungry polar bears might severely reduce or wipe out nesting snow goose populations.

But in new research, recently published online in the journal Oikos, Rockwell and his team shows that the currently plentiful snow goose population is in no danger from the bears. In fact, the eggs might provide a valuable backup food source as polar bears are forced to end their seal hunts early. For one thing, a snow goose egg is about twice the size of a chicken egg, but it is much more nutritious, said Rockwell, a research associate at the American Museum of Natural History and a professor at the City University of New York.

Downing a goose egg is like “eating a stick of butter,” he said. Rockwell estimates that if a Polar bears eats about 88 snow goose eggs, the bear will be consuming the caloric equivalent of a seal. Snow geese are migratory birds that spend their winters in warmer parts of North America. The birds typically arrive in the Arctic to breed around the end of May and remain through August.  Snow geese are currently considered a species of least concern according to  the International Union for Conservation of Nature, because they have a wide range and a large global population that seems to be increasing. Its time to do something to save these wonderful creature

“Polar bears”

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Toxic algae take over British water bodies

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A combination of mild weather and high levels of phosphate nutrients from agriculture and homes are to blame for the green, porridge-like toxic algae blooms that have blighted British canals and lakes this summer, the Environment Agency has said.

There have been 83 algal incidents so far this year — a month into the three-month algae season — a higher than usual amount, according to the agency. In 2010, the number of incidents reached 225, while the peak year was 2005, when 226 were reported.

It is not yet clear how many of this year’s incidents are blue-green algae. Blue-green algae (Cyanobacteria) are natural inhabitants of many inland waters and estuaries, and form potentially toxic green scum when they die.

These toxin-producing blooms, called harmful algal blooms, have been known to  kill wild animals, livestock and pets, and can be harmful to people. Toxic algae have been detected in high concentrations in Loch Coulter, near Stirling, the Llysy Fran reservoir, in south- west Wales, Malthouse and Ranworth Broads in Norfolk, the Serpentine, in London and the Wishing Tree reservoir, in East Sussex.

Other areas have also suffered excessive amounts of algal blooms, with water activities suspended as British Waterways officials were forced to take action.

The blooms are caused by a surge in algae brought on by a combination of climatic factors including the recent calm, mild weather, drought in some parts of the UK causing slow-moving water, and July’s heavy rain in other parts of the country, which increased the amount of nutrients from fertilizers, sewage and detergents in the waterways.

In humans who have swallowed or swum through the blooms, toxins have been linked to neurological, digestive and skin problems and long-term liver disease.

In 1989, two soldiers taking part in canoe training at the algae-hit Rudyard Lake, in Staffordshire, became severely ill with atypical pneumonia. Others reported abdominal pains, vomiting, diarrhea, blistering of the mouth and sore throats.  Algal toxins have also been major contributors to fish kills. Professor Geoffrey Codd of Dundee and Stirling Universities, who is a leading expert on blue-green algae, said, “It’s possible that those toxins can accumulate in the fish.”

Blue-green algae feed off nitrates from the air and phosphates from the water. The Plant life Wales conservation officer, Ray Woods, said, “When extra phosphates enter the water in sewage and fertilisers, the algae thrive. With nitrogen from the air and the higher phosphate levels, the blue-green algae just keep growing and can become excessive.”

1 in 5 plant species at risk of extinction

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One in five of the world’s plant species – the basis of life on Earth – are at risk of extinction according to a landmark study. At first glance, the 20 percent figure looks far better than a previous official estimate of almost three-quarters but the findings are being greeted with deep concern. The report published on September 29 is the first comprehensive assessment of plants from giant tropical rainforest to the rarest of delicate orchids. It concludes that the real figure is at least 22 per cent and could well be higher as hundreds of species being discovered by scientists each year are likely to be in the “at risk” category.

“We think this is a conservative estimate,” said Eimear Nic Lughadha, one of the scientists at Kew Gardens, London responsible for the project. The previous estimate, that 70 per cent plants were either endangered or critically endangered, was based on what scientists acknowledge were studies heavily biased towards species already thought to be under threat.

The latest study is considered crucial to understanding the level of threat to the entire natural world’s biodiversity, according to Craig Hilton Taylor, of the International Union for the Conservation of Nature (IUCN), which runs the world’s official “red lists” of threatened species. “Plants are the basis of life, and it has many implications,” said Taylor. The results will be presented to world leaders meeting at Nagoya, Japan next month to discuss the world “biodiversity crisis, along with new red lists for vertebrates and several groups of the planet’s millions of invertebrate species”. “This is a base point,” said Lughadha. “What we do from now is going to lead to the future of plants. We need to challenge the idea that plants are there to be exploited by us,” he said.

A climate warning from the deep

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The dispersal of tiny sea creatures in Antarctica has alerted scientists to the vulnerability of Earth’s ice sheets Bryozoans make unlikely prophets of doom. Nevertheless, scientists believe these tiny marine creatures, which live glued to the side of boulders, rocks and other surfaces, reveal a disturbing aspect about Antarctica that has critical implications for understanding the impact of climate change. British Antarctic Survey researchers have found the dispersal of these minute animals suggests a sea passage once divided Antarctica 125,000 years ago. The discovery was made for the ongoing Census of Antarctic Marine Life project and involved comparing bryozoans from the Ross and Weddell seas.

These two seas are separated by the west Antarctic ice sheet, one of the planet’s largest masses of ice. Bryozoans found in the Ross and Weddell seas should have been fairly different in structure if the sheet had been stable and ancient. The two populations would have slowly evolved in different manners, if the sheet was millions of years old.                Bryozoans

But Dr David Barnes and his team discovered that the two populations were almost identical, indicating the two seas must have been connected by a major sea passage in the recent past, around 125,000 years ago. “What we’ve got is these groups of animals that don’t disperse very well because the adults don’t move at all and the larvae are short-lived and sink, so they find it difficult to get around,” says Barnes. “So you’re left with this nice signal of where things used to be connected and, in this case, it appears to be a connection between what is now an ice sheet.”

The impact of the west Antarctica ice sheet melting sufficiently to let a major sea passage extend through it would have been considerable. A complete collapse of the sheet today would lead to a sea-level rise of between 11feet and 16feet, for example, though the event uncovered by Barnes may only have been a partial one. Nevertheless, the research indicates that the great ice sheet, thought to be impregnable, is really highly vulnerable.