Cape Gannet

Overview

The Cape Gannet is a large, gleaming white seabird of southern African waters, closely resembling its northern relative the Northern Gannet but distinguishable by additional black plumage features: a solid black tail and a black band across the secondary flight feathers.

It breeds in large, dense colonies on a small number of offshore islands off South Africa and Namibia, and shares the same spectacular plunge-diving feeding technique as other gannets.

Cape Gannet feathers share the general white-and-black gannet pattern but with extra black features.

• Tail feathers: Solid black, a key difference from the all-white tail of the Northern Gannet.
• Secondary flight feathers: Marked with a black band across the trailing edge, absent in Northern Gannet.
• Primaries: Black, similar to other gannet species.
• Body feathers: White with a yellow-buff wash on the head, often slightly deeper yellow than in Northern Gannet.
• Compared to Northern Gannet: The black tail and black secondary band are the most reliable feather-based distinctions between the two species.

Adults are white overall with black primaries, a black band across the secondaries, and a solid black tail, along with a yellow-buff wash on the head and upper neck. Sexes look alike. Juveniles are dark brown speckled with white, resembling young Northern Gannets, and take several years to reach full adult plumage through successive molts.

Cape Gannets breed in a small number of large colonies on islands off the coasts of South Africa and Namibia, foraging over the productive cold-water currents of the region. Outside the breeding season, they disperse along the southern African coastline and adjacent offshore waters, generally remaining closer to their breeding range than some other gannet species.

Cape Gannets feed by spectacular plunge-diving into schools of small fish, often in large, coordinated flocks that can include hundreds of birds diving in quick succession. They nest in dense, tightly packed colonies on offshore islands, laying a single egg and raising one chick over an extended nestling period. Calls are harsh, repeated braying notes typical of gannets, given constantly at breeding colonies.