Cape Petrel
The Cape petrel is one of the most familiar seabirds of the Southern Ocean, instantly recognizable by its bold black and white checkered upperparts, white belly, and short dark bill. It belongs to the petrel family and uses stiff, outstretched wings to glide effortlessly just above the wave surface, a technique known as dynamic soaring. It feeds mainly on krill, squid, and small fish, snatching prey from the water or diving shallowly. Outside the breeding season it roams vast stretches of the southern oceans, sometimes reaching the coasts of South America, southern Africa, and Australia. Breeding takes place on rocky cliffs of Antarctic and sub-Antarctic islands, where each pair lays a single egg and raises one chick per season. Colonies can be extremely dense and noisy. The species is abundant across its range and is currently listed as Least Concern by the IUCN.
Habitat and distribution
Few seabirds are as closely tied to the Southern Ocean as the Cape petrel. It breeds on rocky cliffs and ledges across Antarctica and sub-Antarctic islands, including South Georgia, the South Sandwich Islands, Heard Island, and the Kerguelen archipelago. Colonies are also found on the Falkland Islands and along the Antarctic Peninsula. Outside the breeding season, birds disperse widely across cold and temperate waters of the Southern Hemisphere, regularly reaching the coasts of South America, southern Africa, Australia, and New Zealand. They tend to favor productive waters where cold currents concentrate prey near the surface. Vagrants occasionally appear as far north as equatorial latitudes, though such records are rare. The species is strongly associated with cold, nutrient-rich waters rather than tropical or warm seas.
Diet
Antarctic krill forms the backbone of the Cape petrel's diet, supplemented by squid, small fish, crustaceans, and carrion when available. To capture prey, birds either seize items from the water surface while in flight or make shallow plunges below the surface. They are opportunistic feeders and readily gather around fishing vessels and whale carcasses, where food becomes easy to access. Large, noisy flocks often form at productive feeding sites, sometimes alongside other petrels, albatrosses, and prions. Feeding activity can intensify at night, when many prey species migrate toward the surface. The availability of krill is particularly critical during the chick-rearing period, as parents must deliver high-energy meals to support rapid growth in their single offspring.
Appearance
Among the seabirds of the Southern Ocean, the Cape petrel is one of the easiest to identify at a distance. Its upperparts display a bold pattern of black and white patches arranged in a checkered design across the wings and back, while the underparts are white with dark margins on the tail and flight feathers. The head is dark brown to black, contrasting with the pale belly. The bill is short and dark, typical of tube-nosed seabirds in the family Procellariidae. In flight, the wings are held stiffly outward, allowing the bird to glide with minimal effort over wave surfaces through a technique called dynamic soaring. Adults of both sexes look alike, and juveniles closely resemble adults from an early age.
Behavior
Sociability defines much of the Cape petrel's daily life. Birds congregate in large, boisterous groups at feeding sites and are well known for shadowing ships across hundreds of kilometers of open ocean, scavenging scraps thrown overboard. On the breeding cliffs, pairs reunite at the same nest site year after year, reinforcing their bond through mutual preening and calling. Nests are simple scrapes on bare rock or narrow ledges, and each pair raises just one chick per season. When threatened at the nest, Cape petrels defend themselves by projecting a stream of stomach oil at intruders, an effective deterrent shared by many members of the petrel family. Colonies are vocal and active, particularly during the hours around dusk and dawn.
Conservation
With a global population estimated in the millions, the Cape petrel is currently listed as Least Concern on the IUCN Red List. Its abundance and wide distribution place it among the most secure seabirds of the Southern Ocean. That said, the species is not entirely free of threats. Longline fishing operations pose a risk, as birds can become hooked while attempting to take bait. Introduced predators such as rats and cats have caused problems at some island colonies, though many core breeding sites remain relatively undisturbed. Changes in ocean temperature associated with climate change could alter the distribution and abundance of Antarctic krill, which is central to the bird's diet. Monitoring of breeding colonies and bycatch reduction measures in fisheries remain important for ensuring the species stays secure over the long term.
Technical factsheet
Where it is found
The Cape Petrel can be found in places such as:
Frequently Asked Questions
What does the Cape petrel eat?
Antarctic krill makes up the largest share of the Cape petrel's diet, but it also eats squid, small fish, and crustaceans. Birds snatch prey from the surface while flying or make shallow dives to catch it. They are opportunistic and will gather around fishing boats and whale carcasses to scavenge. During the chick-rearing period, parents rely heavily on krill to deliver the energy their single chick needs to grow quickly.
Where does the Cape petrel live?
The Cape petrel breeds on rocky cliffs across Antarctica and sub-Antarctic islands, including South Georgia, the Kerguelen archipelago, and the Falkland Islands. Outside the breeding season, it roams widely across cold and temperate waters of the Southern Hemisphere, reaching the coasts of South America, southern Africa, Australia, and New Zealand. It strongly favors waters that are cold and rich in nutrients, where prey concentrates near the surface.
How does the Cape petrel fly?
The Cape petrel uses a technique called dynamic soaring, holding its wings stiffly outstretched and gliding just above the wave surface. By exploiting differences in wind speed between the troughs and crests of waves, it can travel vast distances with very little energy expenditure. This style of flight is shared by many birds in the petrel and albatross families and is perfectly suited to life over the open ocean.
Why do Cape petrels follow ships?
Cape petrels are well known for trailing vessels across hundreds of kilometers of open ocean. They do this primarily to scavenge scraps and discarded fish thrown overboard by crews. Ships also create turbulence that can bring prey closer to the surface, making feeding easier. This behavior has made the species very familiar to sailors in the Southern Ocean for centuries, and it often forms large, noisy flocks around vessels.
How do Cape petrels defend their nests?
When an intruder approaches the nest, Cape petrels have a striking defense: they project a stream of stomach oil directly at the threat. This oil is produced in their digestive system and can foul the feathers of other birds, reducing their ability to stay warm and fly. It also has a strong, unpleasant smell. This defense mechanism is common across the petrel family and is effective against both predators and rival birds.
Is the Cape petrel endangered?
No, the Cape petrel is listed as Least Concern by the IUCN, with a global population estimated in the millions. Its wide range and large numbers make it one of the most secure seabirds of the Southern Ocean. However, it does face some risks, including accidental capture on longline fishing hooks and predation by introduced animals such as rats and cats at certain island colonies. Climate change and its effect on krill is also a concern worth monitoring.
How many eggs does a Cape petrel lay?
A Cape petrel lays just one egg per breeding season. Both parents take turns incubating the egg and later feeding the chick by regurgitating food. Nests are simple scrapes on bare rock or narrow cliff ledges, with no elaborate construction. Pairs are known to return to the same nest site year after year. The chick grows relatively quickly thanks to the energy-rich meals its parents bring, primarily consisting of krill and other prey from nearby waters.