Calonectris borealis
The Cory's Shearwater, *Calonectris borealis*, is a majestic pelagic seabird, renowned for its impressive transatlantic migrations. Averaging 45-56 cm (18-22 in) in length with a formidable wingspan of 100-125 cm (39-49 in), it presents a classic "tubenose" profile with long, stiff wings perfectly adapted for dynamic soaring. Its plumage is subtly striking: sooty brown upperparts contrast with gleaming white underparts, a distinctive field mark being the pale primary shaft visible on the unde...
Primarily a pelagic species, inhabiting the open ocean and offshore waters throughout its annual cycle. It only comes ashore to breed, nesting in burrows and rock crevices on remote, rocky islands and coastal cliffs.
Feeds primarily on small schooling fish such as sardines, mackerel, and anchovies, as well as squid and crustaceans. It forages by surface-seizing and shallow plunge-diving, often associating with marine predators like tuna or dolphins that drive prey to the surface.
Cory's Shearwaters are highly gregarious at sea, often forming large rafts on the water or associating with fishing vessels and feeding cetaceans. While generally diurnal for foraging, they exhibit nocturnal activity at their breeding colonies to minimize predation risk from gulls. Their foraging...
The Cory's Shearwater exhibits a fascinating trans-equatorial migratory pattern. Its primary breeding grounds are concentrated on islands in the eastern North Atlantic, including the Azores, Madeira, the Canary Islands, and especially the Selvagens Islands, which host the largest colony. Followin...
Least Concern
- The Cory's Shearwater was named after Charles B. Cory, an American ornithologist and naturalist. - It undertakes one of the longest annual migrations of any bird, traveling thousands of kilometers across the Atlantic. - Despite its impressive size, its primary shaft on the underwing is notably ...