The Northern Gannet (Morus bassanus) is the largest member of the gannet family, Sulidae, and the largest seabird in the northern Atlantic. Both sexes exhibit similar plumage, with adults boasting a predominantly white streamlined body, a long neck, and elongated, slender wings. The species measures 87β100 cm in length and has an impressive wingspan of 170β180 cm. During the breeding season, the head and nape display a buff tinge, more pronounced in males, and the wings are tipped with dark brown-black feathers. The blue-grey bill is long and pointed, set against a backdrop of black, bare skin around the mouth and eyes. In contrast, juveniles are mostly grey-brown, transitioning to white over five years until maturity.
Adult Northern Gannets can be identified by their white bodies, buff-tinged heads, and dark wingtips. The blue-grey bill and black skin around the eyes are distinctive. Juveniles differ with their grey-brown plumage and gradual whitening as they age. The species is larger and thicker-billed than its relatives, the Cape or Australian Gannets, and has more white in the wings and an all-white tail.
Northern Gannets favor nesting in colonies on offshore islands with cliffs, which facilitate easier launching into the air. These locations are typically over continental shelves in cool waters rich with fish like mackerel and herring.
This seabird is native to the Atlantic Ocean's coasts, breeding in Western Europe and Northeastern North America. Its range has expanded northward and eastward, with colonies now established as far as Russia's Kola Peninsula and Bear Island in Svalbard.
Northern Gannets are diurnal foragers, plunge-diving from heights into the sea to catch fish. They are powerful fliers but require a warm-up before taking flight and may struggle to become airborne from flat surfaces. On land, they are less graceful, often having difficulty walking and taking off.
The Northern Gannet is vocal, especially in colonies, with a typical harsh "arrah-arrah" or "urrah-urrah" call. Calls vary in length and intensity depending on context, such as arriving at the colony, fishing, or interacting with mates and chicks.
Breeding takes place in large colonies, with the oldest birds returning first to the sites. Nesting starts in March or April, with a single egg laid per season. The nests, constructed from seaweed and other materials, grow in size throughout the season. Chicks are brooded by the parents' webbed feet and fledge between 84 and 97 days old.
The Northern Gannet can be confused with the Cape or Australian Gannets but is distinguished by its larger size, more white in the wings, and all-white tail. Masked Boobies may also be mistaken for Northern Gannets but are smaller and lack the buff tinge on the head.
Northern Gannets primarily feed on fish by performing high-speed dives into the sea. They forage both near their nesting sites and farther out at sea, sometimes following fishing boats or cetaceans to scavenge discarded fish or offal.
The International Union for Conservation of Nature (IUCN) classifies the Northern Gannet as a species of least concern. Its population is growing, with high breeding success rates and a large, widespread population.