Conservation organizations, such as WWF and Defenders of Wildlife, and the educational website of National Geographic provide facts about narwhals. Narwhals are native to the Arctic waters around Canada, Greenland, Norway and Russia, according to the WWF.
Narwhals are also known as the unicorns of the sea because of their unusual, spiral horns. The mysterious horn is actually a tooth that grows out from their heads, and it can reach lengths of up to 10 feet. Narwhals dive under the sea ice in search of prey and surface through small cracks to get air. Narwhals are under threat from global warming, which endangers their icy habitat, as well as development and pollution related to oil and gas operations, according to Defenders of Wildlife.