The beluga whale (Delphinapterus leucas), is an Arctic and sub-Arctic cetacean. It is one of two living members of the family Monodontidae, along with the narwhal, and the only member of the genus Delphinapterus. It is also known as the white whale, as it is the only cetacean to regularly occur with this colour; the sea canary, due to its high-pitched calls; and the melonhead, though that more commonly refers to the melon-headed whale, which is an oceanic dolphin. Belugas are also called white whales, and their unusual color makes them one of the most familiar and easily distinguishable of all the whales. Calves are born gray or even brown and only fade to white as they become sexually mature around five years of age. Belugas generally live together in small groups known as pods. They are social animals and very vocal communicators that employ a diversified language of clicks, whistles, and clangs. Belugas can also mimic a variety of other sounds. These whales are common in the Arctic Ocean's coastal waters, though they are found in subarctic waters as well. Arctic belugas migrate southward in large herds when the sea freezes over. Animals trapped by Arctic ice often die, and they are prey for polar bears, killer whales, and for Arctic people. They are hunted by indigenous people of the north, and by commercial fisheries that brought some populations, such as those in the Gulf of St. Lawrence, to near collapse.
Belugas are often called the canaries of the sea. They are highly vocal and produce a series of chirps, clicks, whistles and squeals to convey important information to each other. Along with bowhead whales and narwhals, beluga whales are one of the three whales that live only in Arctic waters. They are adapted to the icy cold waters of the Arctic and lack a fin on their back, a dorsal fin. Scientists think that beluga could have evolved without a dorsal fin for good reasons – it makes diving under sea ice easier and helps to reduce heat loss. Instead of a dorsal fin, belugas have a dorsal ridge that is used to break thin sea ice. As climate change continues to warm the Arctic reduce the amount of sea ice, orcas have been spotted in beluga whale habitats. Orcas are a major predator of all three Arctic whale species, including belugas. Less sea ice means less protection from predators. In many parts of the Arctic, beluga whales avoid ship traffic. Underwater noise produced by shipping and other human activities, such as industry, have an impact on beluga whales. This makes it difficult for belugas to communicate with each other and as a result impacts their ability to feed, mate and other important life events.
