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.

Beluga
Belugas live in Arctic and Sub-Arctic waters. Impacts from climate change include: an increase in ship traffic as sea ice declines, oil exploration and extraction, fisheries by-catch, and disruption of the food web. As Arctic waters warm and currents change, the Humpback (a competitor) and the Orca (a predator) may move north and stay longer. Some Beluga populations are also threatened by hunting, pollution and habitat loss.

Bramble Cay Melomys
The Bramble Cay Melomys was the first species to be declared extinct because of climate change. Sea level rise and storm surges washed away its habitat, food and the last of the population. In 2014 scientists went searching in the hopes of starting a breeding program but were unable to find a pair. Other sea birds and turtles that live on the Cay are also threatened by storm surges and sea level rise.

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.