As belugas age, their skin loses pigment cells which causes it to turn white. Only the rims of their pectoral flippers and tail flukes retain their original grey shade. Some Canadian researchers use the Kodak grey scale to describe the colour of belugas, but there is too much variation in the rate at which the belugas turn white for colour to be a reliable indicator of age. Occasionally, belugas encounter killer whales and polar bears. Belugas can get trapped under ice without a breathing hole.
Humans also hunt belugas for food.
Belugas have a diverse diet. They emit clicks from their nasal passages. These clicks travel through water and bounce off objects like ice, food or the ocean floor. Belugas listen for the echoes of these clicks to determine where their food is located. The St. Lawrence belugas are affected by industrial pollution which is concentrated in the fish they eat.