Balearic Shearwater

Identification

The Balearic shearwater is a medium-sized seabird measuring 34–39 cm in length with a wingspan of 78–90 cm. It is best identified by its characteristic "shearing" flight pattern: the bird dips from side to side on stiff wings with minimal wingbeats, its wingtips nearly touching the water as it travels low over the sea. In flight, it resembles a flying cross, with wings held at right angles to the body. The plumage shifts dramatically in appearance as the bird moves—dark brown upperparts and paler undersides are alternately exposed, creating a striking contrast between dark and dirty white as it skims the waves.

Apart from its less contrasting plumage, the Balearic shearwater closely resembles the Manx and yelkouan shearwaters found elsewhere in the Mediterranean. Indeed, genetic studies suggest very little difference between the Balearic and yelkouan shearwaters. For reliable field identification, a combination of morphological characteristics and careful observation is recommended, particularly given the overlap in their ranges and the existence of mixed breeding colonies.

Range & Habitat

This species breeds exclusively on islands and coastal cliffs in the Balearic Islands. While most populations winter in the same waters, some birds venture into the Atlantic in late summer, occasionally reaching as far north as Great Britain and Ireland. The Balearic shearwater has a distinctly Mediterranean focus, though its winter range overlaps with the yelkouan shearwater across the Central Mediterranean.

Behaviour & Diet

The Balearic shearwater is a highly gregarious species, often encountered in large numbers when observed from boats or coastal headlands, particularly during autumn. At sea, these birds remain silent, but their breeding colonies transform dramatically after dark—the night air comes alive with raucous cackling calls that are higher-pitched than those of the Manx shearwater. The species nests in burrows and caves, visiting these sites only under the cover of darkness to avoid predation by large gulls.

Balearic shearwaters feed primarily on fish and molluscs. Unlike some seabird species, they do not follow boats, making them less habituated to human vessels than certain other shearwater species.

Best Time & Places to See It

Autumn is the prime season for observing Balearic shearwaters in large numbers. The Balearic Islands themselves are the core location for this species, where they can be observed from boats and headlands throughout their range. Late summer, when some individuals venture into Atlantic waters, offers opportunities to see them further north, including off the coasts of Great Britain and Ireland for those willing to travel.

Photography Tips

Photographing Balearic shearwaters from a boat or coastal vantage point during autumn will yield the best opportunities to capture their distinctive flight. Their low, rapid movement over the water and rapid wing dips present a dynamic challenge. Position yourself to capture the characteristic cross-like silhouette and the alternating exposure of dark and pale plumage as they bank and turn. Dawn observations at breeding colonies may reveal birds returning from feeding, though these must be conducted respectfully to avoid disturbance. The species' critically endangered status demands that all observation be carried out with conservation ethics paramount.