Scopoli's shearwater (Calonectris diomedea ) is a seabird in the petrel family Procellariidae. It breeds on rocky islands and on steep coasts in the Mediterranean but outside the breeding season it forages in the Atlantic. It is brownish grey above with darker wings and mostly white below. The bill is pale yellow with a dark patch near the tip. The sexes are alike. It was formerly considered to be conspecific with Cory's shearwater.
Scopoli's shearwater is 45–52 cm (18–20 in) in overall length with a wingspan of 112–122 cm (44–48 in). The upperparts are brownish-grey with most feathers fringed with a lighter brown. The wings are a darker brown. The upper tail-coverts are tipped whitish and the tail is dark brown. The underparts are mostly white with a brown border which is most prominent of the trailing edge of the wing. The bill is pale yellow with a dark patch near the tip. The legs and feet are a pale flesh colour. The sexes are similar in appearance but the male is on average slightly larger than the female.
The appearance is very similar to Cory's shearwater and the two species can be difficult to distinguish. The underside of the wing of Scopoli's shearwater has more white on the primary feathers at the wingtip, in particular the outermost large feather (P10). The Cape Verde shearwater is smaller and is significantly darker above.
Scopoli's shearwater breeds on islands in the Mediterranean from the Chafarinas Islands off the Moroccan coast in the west to the Dodecanese near Turkey in the east. The largest colony is on the rocky island of Zembra, 13 km (8.1 mi) off the Tunisian coast. The colony contains between 141,000 and 223,000 breeding pairs which represents more than 75 percent of the global population. Other large colonies are on the island of Linosa in the Strait of Sicily, and on the Balearic Islands.
At the end of October, after the breeding season, Scopoli's shearwaters migrate to the Atlantic and stream out of the Mediterranean through the Strait of Gibraltar. They return to the Mediterranean at the end of February. Studies using light level geolocators have found that birds tagged either on the island of Linosa or on the Pantaleu islet in the Balearic Islands wintered in regions associated with major upwellings in the south east Atalantic. The birds either foraged off the coast of West Africa in the upwelling associated with the Canary Current or continued further south and foraged in the Benguela Current off the coast of Namibia.
Scopoli's shearwater mainly feeds on small fish, but it also consumes cephalopods and crustacean. It feeds by skimming over the surface or by surface feeding but only rarely plunges completely beneath the surface. Sometimes it will follows whales and tuna to pick up food scraps and to catch small fish driven to the surface. It will also scavenge discards from fishing vessels.
