The Southern Lapwing (Vanellus chilensis) is a wader in the family Charadriiformes. It is a common and widespread resident throughout South America, except in the jungles of the Amazon and the Andes. This bird is particularly common in the basin of the River Plate. Vagrant individuals can also be found in southern Central America.

It is the national bird of Uruguay, where it is called tero. Due to its bold and pugnacious nature it has become the namesake and mascot of the Uruguay national rugby union team, Los Teros. In Brazil it is widely known as quero-quero.

Description

This lapwing is the only crested wader in South America. It is 12-13 in (31-33 cm) in length and weighs 11 oz (300 g). The upperparts are mainly brownish grey, with a bronze glossing on the shoulders. The head is particularly striking; mainly grey with a black forehead and throat patch extending onto the black breast. A white border separates the black of the face from the grey of the head and crest. The rest of the underparts are white, and the eye ring, legs and most of the bill are pink. It is equipped with red bony extensions under the wings (spurs), used to intimidate foes and fight birds of prey.

During its slow flapping flight, the Southern Lapwing shows a broad white wing bar separating the grey-brown of the back and wing coverts from the black flight feathers. The rump is white and the tail black. The call is a very loud and harsh keek-keek-keek.

The sexes are similar in plumage, but young birds are duller, with a shorter crest and browner face and breast.

There are three or four subspecies, differing slightly in head coloration and voice. Vanellus chilensis fretensis from Patagonia is sometimes included in the nominate subspecies V. c. chilensis. The northern subspecies - V. c. cayennensis from north and V. c. lampronotus from south of the Amazon River - are sometimes separated as a distinct species, Vanellus cayennensis. These two subspecies have a browner head - particularly the northernmost birds - and the white face band (broad in the northern and narrow in the southern one) does not reach to the center of the crown. However, birds from the general region of Uruguay apparently intergrade .

V. c. chilensis (Valdivia, Chile)

Nesting V. c. lampronotus threatening photographer. Note spurs protruding from wrists.

Nest of V. c. lampronotus with small xlutch

Calls

In prehistoric times the species seems to have been more widespread. Late Pleistocene lapwing bones from Florida were initially described as Dorypaltus prosphatus but have since been regarded as indistinguishable trom those of the Southern Lapwing of our time, except by being smaller. Though they may not be specifically distinct, the lack of this birds' occurrence out of South America on a regular basis today suggests that they may be better considered a paleosubspecies V. c. prosphatus. This would have disappeared as the last ice age ended, but biogeography suggests that the species must also have occurred in Central America and/or the Caribbean. The entirely extinct prehistoric species V. downsi is closely related to the Southern Lapwing found in California; its remains have been found at the La Brea Tar Pits in Los Angeles. Separated by the Rocky Mountains, V. downsi makes an unlikely ancestor to the Southern Lapwing, but it is certainly possible that it was a northwestern sister species.

Ecology

This is a lapwing of lake and river banks or open grassland. It has benefited from the extension of the latter habitat through widespread cattle ranching. It was first recorded on Trinidad in 1961 and Tobago in 1974, and has rapidly increased on both islands. When not breeding, this bird disperses into wetlands and seasonally flooded tropical grassland.

Its food is mainly insects and other small invertebrates, hunted by a run-and-wait technique, mainly at night. This gregarious species often feeds in flocks.

The Southern Lapwing breeds on grassland and sometimes ploughed fields, and has an aerobatic flapping display flight. It lays 2-3 (rarely 4) olive brown eggs in a bare ground scrape. The nest and young are defended noisily and aggressively against all intruders.