The time has come, the walrus says, to talk of climate change

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Andrew Trites, a marine biologist, says Arctic mammals will need to adapt to survive climate change at the “Big Thaw” seminar during the AAAS annual meeting.

By Jennifer Draper

Walruses and other marine wildlife on the Arctic front line are losing the battle against the global warming. The climate change  invasion is threatening animal populations already and the health of indigenous people who depend on them for survival, experts say.

Scientists revealed how climate change dishes out consequences for the ecosystem Friday during the seminar, “The Big Thaw: Impacts on Health of Marine Mammals and Indigenous People in the Arctic.”  This is one of dozens of sessions drawing thousands of scientists to the American Association for the Advancement of Science annual meeting in Chicago.

“Walruses, ice seals, polar bears — they no longer have habitats as they used to,” said biological oceanographer Sue Moore, citing the 75 percent volume loss and a 50 percent area loss in Arctic sea ice during the last decade. “It’s a new normal.”

The “cog of climate change” turned by human activities, continues to force species — from plankton to humpback whales — to endure increased exposure to ships that cause underwater sound pollution and the risk of being struck by a ship, said Moore, an Arctic expert at the National Oceanic and Atmospheric Administration.

NOAA walruses on Bering Sea ice, Alaska, June 1978
The walrus population may be at risk due to a dramatic loss of sea ice, experts say. Photo/NOAA

Marine mammals’ bodies and behavior in particular indicate the health of ecosystem, Moore said, and the “enormous changes” are already evident by massive walrus haulouts and drowning polar bears.

“They have to swim too far a distance getting from one place to another with the loss of sea ice habitat,” said Alaska Veterinary Pathology Services researcher Kathy Burek Huntington. “The Arctic and its inhabitants are what I call a canary in a coal mine.”

People living in Arctic communities face greater risks to food supply due to emerging diseases affecting ice seals and Pacific walruses that cause skin lesions, lethargy and respiratory problems, according to Department of Wildlife Management Biologist Raphaela Stimmelmayr.

The “Big Thaw” experts build upon each other’s research like carpenters, collectively identifying how Arctic ecosystems are restructuring under the pressure of global warming.

Warmer conditions may contribute to extra harmful algal blooms, biotoxins and other contaminants, according to Huntingon, that not only will affect animals, but human health as well.

Climate change is also fostering the expansion of water parasites exposing marine mammals to fatal infections and causing disease outbreaks for Arctic wildlife and people, according to National Institutes of Health researcher Mike Grigg.

But can Arctic marine mammals, like the walrus, adapt to global warming?

“They don’t have boats. They need ice,” said Andrew Trites, director of the North Pacific Universities Marine Mammal Research Consortium.

Arctic environmental changes will hurt some species and benefit others, he said. The biggest losers will be those with small populations like the walrus or the narwhal, which are “too specialized” to adapt to new climate conditions. A shorter ice season means polar bears will have to endure a longer fasting period, Trites said, as well as shifts in the quality and quantity of prey species.

“For the true Arctic species, their life has evolved by survival in a very harsh climate,” Trites said. “It’s been tuned to this timing of ice and presence of prey that coexist with the ice. The question now is ‘Do they have the flexibility to sync their life cycles to the new normal?’”