Black Tern

Identification

The Black Tern is a small tern, 25 cm long with a 61 cm wingspan, weighing around 62 grams. Adults are strikingly dark in breeding plumage, featuring a black head, neck, and belly contrasted against a dark grey back and white forewing. A distinctive dark triangular patch marks the face in front of the eye, while the tail is light brownish-grey and notably square-shaped. The bill is short, slender, and slightly decurved, while legs are short and dark. In non-breeding plumage, much of the black is replaced by grey, creating a duller appearance with pale feather-edgings on the upperparts. Juveniles display a broadish white collar and greyish-brown smudges along the breast sides. In flight, these birds appear slim and agile, with full, dynamic wing-beats and often erratic movements as they hunt.

Range & Habitat

Black Terns breed in freshwater marshes across most of Canada, the northern United States, and much of Europe and western Asia. They typically nest on floating material in marshes or on the ground very close to water, laying 2–4 eggs. Historically abundant in England's eastern Fens, particularly Lincolnshire and Cambridgeshire, extensive drainage eliminated the English breeding population by around 1840, with only sporadic recolonisation attempts since the mid-twentieth century. In winter, North American populations migrate to the coasts of northern South America and open ocean, while Old World birds winter in Africa.

Behaviour & Diet

Black Terns are distinctly different from typical diving terns; rather than plunging into water, they forage on the wing, picking up food items at or near the water's surface and catching insects in flight. They primarily consume insects and fish, supplemented by amphibians. Their high-pitched "kik" call becomes deafening when large flocks gather. The species is vocal and active, with erratic diving patterns that make them engaging to watch during feeding sessions.

Best Time & Places to See It

Black Terns are best observed during the breeding season in their freshwater marsh habitats across Canada, the northern United States, Europe, and western Asia. For European visitors, breeding populations are most easily found in continental marshes, as the species is now a rare vagrant to Britain and Ireland. Winter sightings occur along coastal areas of Africa and South America. Migrants may appear along coasts during spring and autumn passage periods.

Photography Tips

Photograph Black Terns during active foraging sessions when their erratic flight and dynamic wing-beats create compelling images. Their contrast between dark and pale plumage is most striking in breeding season when they display full black coloration. Position yourself near productive marsh areas where insects and small fish are abundant, allowing the birds to hunt close to you. Early morning light often enhances the subtle blue sheen visible on their plumage in bright sunlight. Capture their characteristic square tail and distinctive facial markings when birds are in level flight or hovering before a feeding dive.