Australian Tern

A boldly patterned large and chunky shorebird of southern South America and Falklands. Favors rocky coastlines and adjacent river mouths, but also frequent on nearby grasslands and lakeshores. Associates readily with other oystercatchers. Told from American Oystercatcher by its glossy black head and upperparts that lack the white shoulder spur. In flight the distinctive upperwing pattern with big white panel on trailing edge separates it from American. At close range, also note the yellow eyering (red on American). Voice is also very distinct from other oystercatchers.

This large swallow has rusty-red underparts, a pale buff throat, and a white leading edge to the underwing that is obvious only in flight. It is mostly resident, although it is also a wet season migrant to the north of its range. Pairs prefer wooded savanna, nesting in banks, termite mounds, and often holes in trees, particularly baobabs. The Mosque Swallow may be confused with the juvenile Rufous-chested Swallow, but it lacks the latter species’ dark “ear-flaps” and buffy forward part of the underwing.

A slender tern with a short bill. Breeding adults are dark-capped with an ashy-gray body, a strongly contrasting white cheek stripe and rump, and a reddish bill and legs. In flight, underwings and uppertail are mostly grayish. In non-breeding plumage resembles other non-breeding terns, but note structure. Restricted to a handful of subantarctic islands, where it forages in inshore waters; common on Kerguelen and uncommon on Crozet and Marion. In breeding plumage, the larger Antarctic Tern is paler gray than Kerguelen, with a larger bill and whitish (not grayish) uppertail and underwings. Arctic Terns (in non-breeding plumage) only overlap with Kerguelen Terns (in breeding plumage) in austral summer.