3. Narwhal
The narwhal, often called the unicorn of the sea, is an enchanting creature of the Arctic waters. Its most striking feature is the long, spiral tusk that extends from the upper jaw, which is actually an elongated tooth. This tusk, which can grow up to 10 feet, has inspired myths and legends for centuries. Narwhals are well-adapted to the icy Arctic environment, using their tusks in social interactions and sensing changes in the environment. These cetaceans primarily feed on fish, squid, and shrimp, contributing to the delicate balance of their frigid marine ecosystem.