Narwhal

The rarest of whales, the Narwhal—"unicorn of the ocean"—has two teeth, one of which can grow more than nine feet long in the male. The tooth is sensitive to temperatures and chemicals in the water and scientists think it enables males to find food as well as females ready to mate. Narwhals dive deeper than any whales—as deep as 5,000 feet—and stay under for 25 minutes before surfacing for air.

The Narwhal lives mainly in the Atlantic Arctic. Because of specialized habitat, narrow range and limited diet (Arctic cod and halibut), it is one of the Arctic species most vulnerable to climate change. The Narwhal breeds in bays and fjords, moving offshore during winter to areas of heavy ice pack, breathing through the few cracks. Sudden or extreme temperature change can cause these cracks to freeze shut, trapping the whales. Other threats are illegal hunting, industrial activities, and risks from oil development, exploration and shipping in the Arctic.

Other animals effected by climate change

Ringed Seal
All populations of Ringed Seals are expected to be adversely affected by climate change because of dependence on sea ice and snow dens for breeding, protecting pups, moulting and resting. Early warming causes pups to separate prematurely from their mothers. As sea ice declines, other threats are fisheries by-catch, increased shipping, tourism and development. Seals are vulnerable to disease from heavy concentrations of pollutants that have accumulated in the Arctic food web.

Bicknells Thrush
The breeding habitat of Bicknell's Thrush is primarily restricted to mountain spruce forests of Northeastern US and Canada. They winter in the Caribbean and spring migration north is cued by day length. If spring arrives early in the north and the Thrushes arrive at their normal time, the abundance of food—insects and fruit—would already have peaked. Warming temperatures also produce an abundance of spruce and fir cones—feeding and increasing the population of Red Squirrels, a main predator of eggs and chicks. Storms and hurricanes threaten the Thrush's tropical winter habitat. Pollution, logging and deforestation threaten their spring breeding and winter habitats.

Ivory Gull
Ivory Gulls are almost entirely dependent on sea ice and glaciers for nesting and food foraging. They feed on fish and shellfish that thrive near the edge of the ice, and on the remains of seals left by Polar Bears. Seal blubber is a source of heavy contaminants—Ivory Gull eggs show a higher concentration of mercury and pesticides than any Arctic sea bird. Other threats are illegal hunting and disturbance from diamond mining in the Canadian Arctic.

Arctic Fox
The Arctic tundra is a region of shrubs, grasses and permanently frozen subsoil. Warming could change the tundra to boreal forest—habitat for the Red Fox. The Red Fox, a predator and a competitor for food, is already beginning to migrate north into the Arctic Fox's territory. Milder tundra weather also causes changes in the population of lemmings and rodents—main food for the Arctic Fox.