Manx Shearwater

Identification

The Manx shearwater is a medium-sized seabird, measuring 30–38 cm in length with a wingspan of 76–89 cm and weighing 350–575 g. Its most distinctive feature is its striking black-and-white plumage: black upper parts contrasting sharply with white undersides. In flight, this creates a dramatic visual effect as the bird alternates between showing its dark back and pale belly, appearing almost like a "flying cross" as it banks low over the water.

The species exhibits the characteristic "shearing" flight typical of its genus, moving from side to side on stiff wings with minimal wingbeats, often with wingtips almost touching the water surface. This low, purposeful flight style is one of the best ways to identify the species at sea.

Range & Habitat

The Manx shearwater is entirely marine and typically flies within 10 metres of the sea surface. Its breeding colonies are scattered across the north Atlantic Ocean, including the United Kingdom, Ireland, Iceland, the Faroe Islands, France, the Isle of Man, the Channel Islands, the Azores, Canary Islands, and Madeira. The largest populations, totalling more than 300,000 pairs, are concentrated on islands off Wales, Scotland, and Northern Ireland, with three islands—Skomer, Skokholm, and Rùm—holding three-quarters of all British and Irish breeding birds.

The species nests in burrows on small islands, which it visits exclusively at night. Iceland supports 7,000–9,000 breeding pairs, while the Faeroes hosts at least 15,000 pairs. Other populations remain small, typically numbering only a few hundred pairs. More recently, the species has colonised northeast North America, with breeding first recorded in 1973.

Behaviour & Diet

Manx shearwaters are notably silent at sea, even when gathered in large numbers off breeding colonies. However, they become vocally active during nocturnal visits to their nesting burrows, calling in flight, on the ground, and within burrows—though moonlight suppresses vocalization. Their repertoire consists of raucous croons, howls, and screams in short syllables that become progressively weaker and throatier. Males produce distinctive clear, ringing tones absent from the harsher calls of females, creating an obvious difference when pairs duet.

The nocturnal vocalizations are notorious for their eerie, unsettling character, earning the species the local nickname "Devil Bird" in various parts of the world. The species has remarkable visual adaptations for its lifestyle: a specialized retina with a narrow band of heightened sensitivity helps detect prey near the sea surface, while nocturnal vision adaptations—particularly a lens-dominated refractive system—allow night navigation. The birds likely supplement vision with smell and hearing to locate their nests.

Best Time & Places to See It

To observe Manx shearwaters, visit major breeding colonies during the nesting season, particularly the islands off Wales, Scotland, and Northern Ireland. Skomer, Skokholm, and Rùm are the most significant sites, collectively holding the majority of British and Irish birds. The Faroe Islands and Iceland also support substantial populations worth visiting.

Since the species visits colonies only at night, the best viewing opportunities occur during evening hours and darkness when birds return from the sea. Daytime observations are possible from boats or coastal vantage points where low-flying birds crossing the water can be spotted using their characteristic shearing flight pattern.

Photography Tips

Photographing Manx shearwaters presents unique challenges due to their nocturnal habits and rapid, low-level flight. For daytime pelagic photography, position yourself where birds cross between feeding grounds and colonies, keeping the sun angle favorable for capturing the contrast between their black upperparts and white undersides.

The bird's low, dynamic flight and cross-like silhouette make it visually striking but demanding to photograph. Fast shutter speeds are essential to freeze the characteristic banking motion. Patience and knowledge of local flight patterns—particularly timing evening departures and returns to colonies—will maximize your opportunities to capture this distinctive seabird in its natural marine habitat.