The Cape Verde Shearwater is a medium-large seabird of the petrel family that breeds only in the Cape Verde archipelago off West Africa. It closely resembles the larger Cory's Shearwater, with which it was once lumped, but is distinctly smaller and slimmer with a more slender, darker bill. On the wing it has a lighter, more agile flight than its bulkier relative.
Like other shearwaters it is superbly adapted to life over the open ocean, coming ashore only to breed. It nests colonially on rocky islets and cliffs, and after breeding it disperses widely across the Atlantic, following productive upwelling waters. It is listed as Near Threatened, largely because of the traditional harvesting of its chicks for food.
This is a slim, long-winged shearwater with a dark grey-brown head and upperparts and clean white underparts. Its smaller size and slender dark bill, without the bright yellow base of Cory's Shearwater, are the key features.
| Size | Medium-large shearwater, around 36 cm long, clearly smaller than Cory's Shearwater |
| Upperparts | Dark grey-brown head and back, darker and more contrasting than Cory's |
| Underparts | White below with dark wing margins |
| Bill | Slim and dark, lacking the prominent yellow base of Cory's Shearwater |
| Flight | Stiffer, more rapid wingbeats and a lighter, more shearwater-like flight |
| Range clue | Breeds only in Cape Verde; the default large shearwater there |
At sea the Cape Verde Shearwater is generally silent. At the breeding colonies, however, it becomes noisy after dark, giving wailing, cackling, and crowing calls as birds fly in and move around their nest sites. This nocturnal chorus at the colony is characteristic of the shearwater family and helps mates and neighbours locate one another in the dark among the rocks.
The species breeds only in the Cape Verde islands in the Atlantic off West Africa, with the largest colonies on Raso, Branco, and Brava. It nests in cliff hollows, among boulders, and on offshore rocks. Outside the breeding season it ranges widely over the Atlantic, frequenting the rich upwelling waters off West Africa and occasionally wandering to the South Atlantic and the coasts of the Americas.
All feeding takes place at sea. The diet is made up of small fish, squid, and other marine animals, which the bird catches by seizing prey at or just below the surface, sometimes making shallow plunges. Like many seabirds it is drawn to areas of upwelling where cold, nutrient-rich water concentrates prey near the surface.
Breeding is colonial and seasonal. Birds come ashore only to nest, laying a single egg in a cliff hollow, rock crevice, or space under large boulders. Incubation runs through the northern summer, roughly May to July, and chicks fledge from late September into November. Because each pair raises only one chick a year, the harvesting of young birds for food has a heavy impact on the population.
- Cory's Shearwater: The larger, bulkier relative with a yellow-based bill it was once lumped with
- Scopoli's Shearwater: A closely related Mediterranean shearwater in the same genus
- Great Shearwater: Another large Atlantic shearwater with a dark cap and white collar
How is the Cape Verde Shearwater different from Cory's Shearwater?
It is noticeably smaller and slimmer, with a darker head and upperparts and a slender dark bill that lacks the bright yellow base seen on Cory's. Its flight is also lighter and more agile.
Where does it breed?
It breeds only in the Cape Verde archipelago, with the main colonies on the islands of Raso, Branco, and Brava.
Why is it Near Threatened?
Its breeding range is very limited and thousands of chicks are still harvested for food each year, which has caused declines. It is also sensitive to introduced predators at its colonies.
How many eggs does it lay?
Like other large shearwaters it lays just a single egg per year, so breeding success is slow to recover from losses.