Arctic Tern

Identification

The Arctic tern is a medium-sized tern measuring 33–36 cm in length with a wingspan of 76–85 cm and weighing around 100 g. During breeding season, these elegant birds are strikingly marked with grey and white plumage, a blood-red beak and feet, a black crown and nape, and white cheeks. The mantle is grey with white-tipped scapulars, the upper wing is grey with a white leading edge, and the deeply forked tail is whitish with grey outer webs. In winter, the forehead becomes partly white and the bill and legs turn black, providing a useful distinguishing feature for field identification.

Juveniles also display a partly white forehead and can be separated from similar species by the narrow pale orangey-brown fringes on their grey mantle feathers. The tern's high aspect ratio wings and deeply forked tail are characteristic features that aid identification in flight, where Arctic terns are particularly graceful and buoyant.

Range & Habitat

The Arctic tern has a circumpolar breeding distribution covering Arctic and subarctic regions across Europe, Asia, and North America. In Europe, the species breeds as far south as Brittany, while in North America it extends to Massachusetts. During the northern summer, these birds inhabit coastal regions in cooler temperate zones. This remarkable species is strongly migratory, spending the southern summer at sea reaching the northern edge of the Antarctic ice before returning to breeding grounds approximately six months later.

The shortest distance between Arctic breeding grounds and Antarctic wintering areas is 19,000 km, yet individual birds often follow convoluted routes that substantially exceed this distance, taking advantage of prevailing winds. Birds breeding in Iceland and Greenland average annual round-trip migrations of about 70,900 km, while some individuals have been recorded travelling over 96,000 km in a single year. Outside the breeding season, Arctic terns are rarely seen from land, as they migrate far offshore.

Behaviour & Diet

Arctic terns are long-lived birds, with many individuals reaching 15 to 30 years of age and a recorded maximum lifespan of 31 years. During their extended lifespans, these birds experience more daylight than any other creature on the planet, enjoying two summers each year as they migrate between polar regions. Their remarkable migration strategy allows them to exploit abundant food resources in both hemispheres.

The species feeds primarily on fish and small marine invertebrates. Arctic terns are abundant globally, with an estimated two million individuals in the population. Historically, exploitation reduced numbers in the southern reaches of their range, though current population trends for the species as a whole remain unclear.

Best Time & Places to See It

To observe Arctic terns during breeding season, visit circumpolar coastal regions during the northern summer months. Notable breeding areas include northern Scandinavia, Iceland, Greenland, and northern Canada. The Farne Islands in Northumberland, UK, support breeding populations and offer reliable sighting opportunities. During winter months, Arctic terns are present at sea near the Antarctic ice, making them inaccessible to most land-based observers.

Since Arctic terns migrate sufficiently far offshore and are rarely seen from land outside the breeding season, dedicated pelagic boat trips or visits to breeding colonies during summer offer the best opportunities for encounters. The species' long-distance migration route means individuals pass through various coastal regions during spring and autumn, though sightings remain sporadic away from established breeding sites.

Photography Tips

The Arctic tern's striking breeding plumage—with its bright red bill and feet contrasting against grey and white feathers—makes it an attractive photographic subject during the northern summer. Photograph birds at breeding colonies where they are relatively approachable and active. The tern's graceful flight and deeply forked tail are best captured using a fast shutter speed to freeze motion, while their high aspect ratio wings create elegant shapes in flight photography.

The transformation to winter plumage, with the forehead becoming partly white and the bill turning black, offers a different photographic opportunity. Early morning and late evening light will enhance the subtle grey tones of the plumage and highlight the distinctive markings. Patience at known breeding sites will reward photographers with opportunities to capture these long-distance champions in their natural habitat.