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.

Adelie Penguin
In winter, the sun doesn't rise south of the Antarctic Circle. If Antarctic sea ice decreases and does not extend far enough to the north, Adélie Penguins, during their winter migration, may not be able to reach the sunlight needed to navigate, hunt and avoid predators—they won't dive in the dark. Other threats are oil pollution, fishing and disturbance of colonies from research stations and aircraft.

American Pika
American pikas occupy talus—rock piles that accumulate at the base of a slope—at high elevations in western mountains. Pikas are thought to be a prime example of the potential effects of climate change because they are sensitive to warm temperatures and rely on insulation provided by snow to survive cold winter temperatures. However, several recent studies indicate that pikas can be resilient to each of these factors. Most pikas in the Sierra Nevada survived the winter of 2014, when there was almost no snowpack. Pikas persist in many hot localities as well, demonstrating their ability to cope with high temperatures.

Sockeye Salmon
For decades wild salmon populations have been in decline from human causes: over fishing; habitat degradation—logging, mining, agriculture and dams; pollution; and interaction with hatchery or farmed salmon. These conditions and threats may hinder their ability to adapt to the effects of climate change. Salmon thrive at specific freshwater temperatures—warming air raises water temperature. Early snow melt and increased rains cause physical changes to spawning streams.