Around the arctic circle, Belugas live in groups. In the autumn they migrate to the South and return to the icy waters in spring. Thanks to their sonar they direct themselves through the mazes formed under the ice floe by emitting rattles. Their sonar is the most developed amongst all cetaceans. As the narwhal does with his horn, belugas can at once create an opening with their bulging forehead to reach for air from the surface.