Antarctic Tern

Overview

The Antarctic tern (Sterna vittata) is a medium-sized seabird in the family Laridae, found throughout the southern oceans on small islands and Antarctic mainland shores. Despite its name, it does not undertake long polar migrations like the Arctic tern, instead remaining close to its breeding islands year-round.

Identification

• Size: Medium-sized tern, 35–40 cm long with a 74–79 cm wingspan, weighing 150–180 g.
• Breeding plumage: Light grey body and wings with a white lower back and deeply forked tail; features a distinctive black cap extending from the nape to the bill and bright red bill, legs, and feet.
• Non-breeding plumage: Black cap reduced to behind the eyes, lighter underparts, and a dull reddish-black bill.
• Song: Noisy around roosts, producing a 'trr-trr-kriah' call in flight or fishing, and a 'chrrrr' to defend nests.

Habitat

Ranges widely across sub-Antarctic islands and the Antarctic continent, preferring rocky islets, cliffs, and beaches inaccessible to mammalian predators such as cats, rats, and sea lions. Outside the breeding season, it frequents ice edges in Antarctica and may be found on the shores of South Africa and other southern continents.

Diet

An opportunistic feeder that primarily consumes small fish and crustaceans, including Antarctic krill. It forages gregariously near the shore in the kelp zone, hovering above the sea to plunge-dive or submerge its bill, and occasionally scavenges in the intertidal zone.

Did you know?

The specific epithet 'vittata' is derived from the Latin vittatus, meaning 'banded'. The global population of this species is estimated at approximately 140,000 individuals, with the majority belonging to the S. v. gaini subspecies.