Whales, dolphins and porpoises belong to the same order called cetaceans. All three of them are found in the Arctic seas. Many species of dolphins are found in these waters, but only one species of porpoise inhabits the Arctic. Dolphins and porpoises are to be found in the Southern Arctic Ocean during the summer months when the waters are warmer and free of ice, and food id plentiful.
As toothed carnivores, all dolphins and porpoises eat meat. This is largely consumed in the form of fish, especially those that swim in vast schools of thousands. Dolphins and porpoises also eat molluscs, and even a crustacean or two. Most species of dolphins as well as most porpoises weigh an average of 90 to 250 kg, and are 1.8 to 2.4 meters long. On an average, they consume between 10 and 22 kg of food each day.