The Common Goldeneye (Bucephala clangula) is a medium-sized diving duck that is widespread throughout the Northern Hemisphere. It is approximately 16 to 20 inches in length with a wingspan of 26 to 33 inches. Male Goldeneyes weigh around 2.2 pounds, while females are slightly smaller, weighing around 1.8 pounds.

The male Common Goldeneye is easily recognizable by its striking black and white plumage. The head is black with a round, white patch extending from the bill to the back of the head. The body is mostly white with a black back, while the wings are black with white patches. The female is less conspicuous, with a brownish-gray body and a brown head. Both sexes have a distinctive, large, oval-shaped white patch on the wing that is visible in flight.

The Common Goldeneye breeds across northern North America, Europe, and Asia. They are migratory, spending their winters in southern coastal areas and freshwater lakes and rivers. In North America, they migrate from their breeding grounds in Alaska and northern Canada to the Great Lakes region, the Northeastern United States, and the Pacific Northwest. In Europe, they can be found throughout the continent and as far south as the Mediterranean and the Black Sea.

Goldeneyes are primarily diving ducks and feed on aquatic invertebrates, fish, and plants. They are known for their ability to dive up to 20 feet deep in search of food. During the breeding season, Goldeneyes prefer to nest in tree cavities near freshwater lakes and rivers. They are also known to use nest boxes provided by conservation organizations.

The Common Goldeneye is a popular game bird and is hunted in some regions. However, their populations remain stable, and they are not considered threatened or endangered. The bird is also a popular subject for wildlife photographers and bird watchers due to its striking plumage and diving behavior.