Jugon

Dewgong is a pinniped Pokémon with a snowy white, furry body. Its fur renders it virtually invisible in snowy conditions. Its face has two black eyes, a black nose, and two tusks extending from its upper jaw. It has a streamlined body with two front flippers and a long flowing tail. Even in extremely cold and ice-packed waters, its tail allows it to be a swift and agile swimmer at speeds of 8 knots. On top of its head is a sharp horn, which allows it to cut through the thickest ice floes.

It lives on icebergs adrift in frigid ocean waters. It thrives in lower temperatures, becoming increasingly more active the colder the weather. By storing thermal energy within its body, it is completely unharmed by even the most intense freezing weather. During daylight hours, it sleeps on bitterly cold ice or under shallow water. However, at night when the temperature drops, it becomes a hunter and searches for prey such as Wishiwashi. Following a meal, it sunbathes on the beach. This raises its body temperature and aids in digestion.

Evolution
Dewgong evolves from Seel.

(Source: Bulbapedia)