Black Tern Identification Guide

Key Field Marks

• Small, delicate tern, about 24 cm long, with buoyant, graceful flight and a short, only lightly forked tail
• Breeding adult: black head, neck, and underparts; contrasting pale gray wings, back, and tail; white undertail coverts
• Non-breeding and juvenile: white forehead and underparts, dark cap restricted to the crown and nape (not extending below the eye as much as in breeding plumage), gray upperparts, and a distinctive dark smudge on the side of the breast ("shoulder patch")
• Thin, mostly black bill and short reddish-black legs
• Feeds by dipping to the water surface or hawking insects in flight rather than plunge-diving like larger terns

Similar Species

• White-winged Tern: breeding adult shows white wing coverts contrasting with black underwing coverts ("black armpits"); Black Tern's underwings are more uniformly pale gray
• Common/Forster's Tern: much larger, longer-billed, pale overall even in breeding plumage, with deeply forked tails and orange or red bills
• Small size, short tail, and buoyant tern-over-water flight style help separate Black Tern from all larger white terns at a glance

Habitat & Range

• Breeds colonially in freshwater marshes, prairie potholes, and shallow wetlands with emergent vegetation
• On migration and in winter, occurs over coastal waters, bays, and sometimes far offshore
• Breeds across the northern United States and southern Canada, and separately across much of Europe and Asia
• North American breeders winter along the coasts of Central America and northern South America; Old World birds winter mainly in coastal and inland Africa

Seasonality

• Present on breeding wetlands from late spring through summer
• A conspicuous migrant in both spring and especially late summer/early autumn, when flocks move along coastlines and large lakes

Voice

• Short, sharp "kik" or "kreek" calls given in flight, less strident than the harsh calls of larger terns
• Generally quieter overall than Common or Forster's Terns