Scientific name: Calonectris diomedea (Scopoli, 1769)
Bird group: Shearwaters and Petrels
Field characters. Length 45-56 cm; wingspan 100-125 cm. A large Shearwater, more heavily built than Great Shearwater and with broader wings. Differs from Great Shearwater in grey-brown head (without black cap) and sides of throat and neck being mottled with grey-brown, gradually shading off into white of throat. Sometimes has white rump. Upperparts dark brown or grey-brown, downward merging with white belly. Underparts purely white, with greyish markings on sides of breast. Flight at distance recalls Fulmar, but silhouette more attenuated and wings much less stiffly beaten and followed by glides with wing-tips held below body. The Atlantic and Mediterranean forms are sometimes separated as Cory's Shearwater, C. borealis, and Scolopi's Shearwater, C. diomedea. The latter is smaller and has a different pattern on the underwing.
Voice. Only on the breeding ground persistent, plaintive sounds and a gull-like scream.
Distribution. Locally abundant breeding bird.
Habitat. Breeds on uninhabited islands or on mountainous terrain. Outside the breeding season an offshore bird, but also in pelagic and inshore waters.
Food. Mainly fish, fish spawn, cephalopods and crustaceans. Feeds at night by surface-feeding.
Eggs. Ground colour white, not glossy. Shape ovate to elliptical. Size 69 x 45 mm (63-74 x 42-53), weight 74 g.