For animals like walruses, which feed on clams and other shallow seafloor organisms, moving the ice to deeper waters effectively moves their grocery store out of reach. Other species already moving north with the ice and running into trouble are diving ducks, ringed seals and polar bears.
Opening the Arctic waters in summer has another effect on the ecology, she said. It allows plankton on the surface to eat up nutrients in the water that would, under ice, drop to the bottom to feed life there. In other words, more open water also effectively cuts off supplies to the walrus's sea-bottom supermarket.
While the open waters may benefit shipping, Grebmeier is worried that vessels using a new Northwest Passage could bring more invasive species to the Arctic, further complicating the growing threats to Arctic natives.
"You'll have winners and losers," said Overland. A small bit of good news, he said, is the good chance that many of the channels in the Canadian archipelago will remain clogged with ice, leaving a refuge for Arctic species.
Related Links:
The Intergovernmental Panel on Climate Change
The Natural Resources Defense Council
Arctic research sponsored by the National Science Foundation
The Arctic Council
