The rounded forehead structure of a beluga whale is called a melon.
A melon is a fatty organ in the whale’s forehead that helps focus and direct sounds used in echolocation. Belugas can alter the melon’s shape, allowing them to modify how sound travels through the water. This ability is particularly useful in the Arctic, where sea ice, shallow channels, and underwater obstacles complicate movement.
The melon gives adult belugas their distinctive bulging forehead. Young belugas have a less prominent shape, and the structure becomes more pronounced as they mature. Belugas produce a wide range of whistles, clicks, and other sounds, which has earned them the nickname “sea canaries.”
The melon is not the animal’s brain, and it is not the blowhole. The blowhole is the opening on top of the head used for breathing. Belugas are toothed whales, so they also do not possess baleen plates. Their scientific name, Delphinapterus leucas, means roughly “white dolphin without a fin.”