Which animal is known as the ''unicorn of the sea''?

The animal known as the 'unicorn of the sea' is the narwhal, a medium-sized toothed whale that lives in the Arctic waters of Canada, Greenland, Norway, and Russia. The narwhal is most easily recognized by the long, straight tusk that protrudes from its head, which is actually a tooth that can grow up to ten feet long in males. The tusk is used for a variety of purposes, including communication, hunting, and navigation.

Narwhals are social animals that live in groups called pods, and they are known for their ability to dive to great depths in search of food, which consists of fish and squid. They are also an important part of Inuit culture and are hunted for their meat, skin, and ivory.