The boobies and gannets (family Sulidae) are a family of birds belonging to the order Suliformes. These large birds are strongly adapted to life in the sea, and are best known by their dramatic plunge-dives from a height into the sea to catch preys, often swimming to chase their preys. Accordingly, they spend most of their lives on the wing at sea. However, they generally forage close to the coast unlike the unrelated tubenoses, adapted to forage in the ocean pelagic zone.
The family comprises 11 species in 3 genera. Odd, basal genus Papasula (1 species) is restricted to Christmas Island in the Indian Ocean. Genus Morus (3 species), commonly known as gannets, breed in temperate and cold offshore islets of Europe, southern Africa and Oceania. Birds of genus Sula (7 species), typically known as boobies, breed in colonies along tropical latitudes. However, all species wander far beyond their breeding grounds out of the breeding period.
Calamocarro beach, Ceuta, Spain, 20 Apr 2025
Northern gannet
Morus bassanus
Breeds in offshore islets of Newfoundland and northern Europe from Iceland and Norway to France, with wintering grounds extending south to the Caribbean and Mediterranean seas. Dark-brown juvenile birds progressively incorporate white feathers onto their plumage until reaching the clean white plumage of adults. This species is a regular winter visitor in Alicante.
Estaca de Bares, Galicia, Spain, 19 Aug 2025
Brown booby
Sula leucogaster
Widespread along tropical and subtropical regions of all oceans. Unlike other members of the family, this species prefers to roost on solid structures rather than the sea surface. The bare skin of their orbital ring is blue in males and yellow in females. Although it is a local rarity, I have seen this species in Galicia (N Spain).
