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Polar bears threatening geese as diet ravaged by climate shift Premium Article ! Your account has been frozen. For your available options click the below button. Options Premium Article ! To read this article in full you must have registered and have a Premium Content Subscription with the The Scotsman site. Subscribe Registered Article ! To read this article in full you must be registered with the site. Sign In Register « Previous « Previous Next » Next » View Gallery Published Date: 18 June 2010 By Emily Beament A CONSERVATION success which has seen barnacle geese numbers bounce back from the brink could be under threat from hungry polar bears struggling to cope with cl

A CONSERVATION success which has seen barnacle geese numbers bounce back from the brink could be under threat from hungry polar bears struggling to cope with climate change, experts said yesterday. The number of Svalbard barnacle goslings that overwintered in the Solway Firth this year was just half that expected, according to the Wildfowl and Wetlands Trust (WWT).

on eggs in the nests

Scientists from the Northwest Territories confirmed that a bear spotted by Inuit hunter David Kuptana on April 8 is a second-generation hybrid. DNA tests made by the NWT Environment and Natural Resources said the animal is a grizzly-polar bear cross breed.

The polar bear features of the animal were its creamy white fur, while its grizzly features were the big head, long claws and a ring of brown hair around its hind. It is being billed as the first recorded second-generation grolar in the area. The department said the grolar was the offspring of a polar/grizzly female with a male grizzly bear.

The cross-breeding of the two species is believed to have been caused by global warming, which have prompted the grizzlies to move to the north, which is polar bear territory. The first sighting of a grolar was in 2006 in Banks Island by an American hunter.

Global climate change is fundamentally disrupting marine ecosystems, especially in the polar oceans, according to two new reviews of scientific research released Thursday in the journal Science.

Changes in temperature, ocean acidity and volume are affecting species from phytoplankton — the microscopic marine plants at base of the food chain — to polar bears, which may lose 68 percent of their summer habitat by 2100. "Climate change is affecting an enormously wide range of physical and biological aspects of the ocean," said John Bruno, a University of North Carolina marine ecologist and co-author of one of the reviews. "Once you start tweaking temperature, everything changes." Photosynthesis by phytoplankton is down six percent since the 1980s, and the organisms themselves are getting smaller thanks to warmer temperatures, the review noted.

Less plankton means less food for fish, which in turn means less seafood for human consumption. Phytoplankton also absorb carbon dioxide from the air and sequester it at the seafloor when they die and sink to the bottom of the ocean. Fewer phytoplankton could mean more human carbon dioxide emissions stay in the atmosphere, Bruno said, further exacerbating the climate change problem.

the ice has been melting earlier in the spring and forming later in the autumn, so that the bears are now spending on average three more weeks on land per year, without food, than they did three decades ago, the researchers say. As a consequence, their body weight in that time has dropped by 60lb, females have lost 10 per cent of their body length, and the west Hudson Bay population has declined from 1,200 animals to 900.

high mercury levels in certain Arctic seals appear to be linked to vanishing sea ice caused by global warming.

The scientists analyzed the mercury content in muscle samples collected from ringed seals between 1973 and 2007. They then compared the levels to the length of the so-called "summer ice-free season," a warm period marked by vanishing sea ice in the seals' habitat. They found that the seals accumulated more mercury during both short (2 months) and long (5 months) ice-free seasons and postulate that this is related to the seals' food supplies. Higher seal mercury concentrations may follow relatively short ice-free seasons due to consumption of older, more highly contaminated Arctic cod while relatively long ice-free seasons may promote higher pelagic productivity and thus increased survival and abundance of Arctic cod with the overall result of more fish consumption and greater exposure to mercury. Longer ice-free seasons resulting from a warming Arctic may therefore result in higher mercury levels in ringed seal populations as well as their predators (polar bears and humans).