Antarctic Mega-Iceberg Suffocates Seals

The findings were recently presented at the Experimental Biology 2008 symposium in San Diego.

"Perhaps the most difficult (to observe) were the abandoned pups. The first rule as a biologist is to let nature take its course -- but is this truly nature when global warming due to human perturbation has instigated the event?" Williams said. "It was exceptionally difficult to walk away from crying pups, knowing that the ice conditions likely cause their mothers to leave."

An Even Longer March for Penguins

Seals weren't the only victims of the B-15 break-off. As fans of the popular film "March of the Penguins" know, the flightless birds must travel long distances to feed at sea before returning to their chicks.

After the drifting iceberg thickened the ice surrounding Ross Island, the researchers observed Adelie penguins struggling to complete a trek that is arduous even under normal conditions.

"With the ice edge so far away it was an impossible travel [a long] distance, so many made a one-way trip and abandoned their nests," Williams said, adding that other biologists in the region reported that many of the nests "failed."

Other Affected Animals

Hannah Carey, past president of the American Physiological Society and a professor of comparative biosciences at the University of Wisconsin School of Veterinary Medicine, told Discovery News that the new research is "compelling" and "may represent one of the best links we have between climate change and the physiology of individual animals, particularly for Antarctic vertebrates."

She said evidence has been mounting that climate-related effects have been disrupting hibernating animals, fish populations, amphibians and other groups, but little work has been done on the physiological impacts to individual animals, and the implications these have for survival of adults and their young.

Carey also said the new research demonstrates how a warming event at the poles can actually lead to ice thickening in other regions, illustrating how "climate change [impacts] on animals can be less predictable and more variable than we may have thought."

James Hicks, professor of comparative and evolutionary physiology at the University of California at Irvine, echoed Carey's comments.

"In a period where global climate change is occurring, scientific studies that investigate the interactions of physiology, behavior, ecology and the physical environment are needed now more than ever," he said. "These types of studies will help us predict how environmental changes may influence animal populations and contribute to our making informed decisions about conservation efforts."

In Human Hands

Both Hicks and Williams hope greater emphasis will be placed on animal physiology studies in the future, as a means of understanding how global environmental challenges can impact animals, including humans.

Williams, however, said the best preventive action "is to get people to recognize the domino effect of human impacts."

"Who could have imagined that driving a car in the U.S. could result in a Weddell seal pup freezing to death in the Antarctic?" she said. "But it did."

Related Links:

Jennifer Viegas' blog: Born Animal

The Impacts of Global Warming

Wildlife of Antarctica

Planet Green

Discovery Earth Live