Recurvirostridae

The Recurvirostridae are a family of birds in the wader suborder Charadrii. It contains two distinct groups of birds, the avocets (one genus) and the stilts (two genera).

Description

Avocets and stilts range in length from Template:Convert and in weight from Template:Convert; males are usually slightly bigger than females.<ref name=B&T>Template:Cite book</ref> All possess long, thin legs, necks, and bills. The bills of avocets are curved upwards, and are swept from side to side when the bird is feeding in the brackish or saline wetlands they prefer. The bills of stilts, in contrast, are straight. The front toes are webbed, partially in most stilts, and fully in avocets and the banded stilt, which swim more.<ref name=B&T/> The majority of species' plumage has contrasting areas of black and white, with some species having patches of buff or brown on the head or chest.<ref name=EoB>Template:Cite book</ref> The sexes are similar.<ref name=B&T/>

Their vocalizations are usually yelps of one or two syllables.<ref name=B&T/>

Distribution and habitat

Avocets and stilts are a cosmopolitan family, being distributed on all the world's continents except Antarctica, and occurring on several oceanic islands. Several species are wide-ranging and a few are locally distributed.

One species, the black stilt of New Zealand, is critically endangered due to habitat loss, introduced predators, and hybridisation with the pied stilt.

Feeding

These species feed on small aquatic animals such as mollusks, brine shrimp and other crustaceans, larval insects, segmented worms, tadpoles, and small fish.

Breeding

Stilts and avocets breed on open ground near water, often in loose colonies. They defend nesting territories vigorously with aggressive displays, and mob intruders and possible predators with a great deal of noise.<ref name=B&T/> They are monogamous, although the pair bonds are not maintained from season to season. Their eggs are light-coloured with dark markings, weighing Template:Convert.<ref name=B&T/> Three to four are laid in simple nests, and both parents share the incubation duties, which last 22 to 28 days.<ref name=B&T/> The banded stilt may breed only every few years, as it breeds on temporary lakes caused by rains in the deserts of Australia. The chicks are downy and precocial, leaving the nest within a day of hatching;<ref name=B&T/> they fledge in 28 to 35 days.<ref name=B&T/> In all species except the banded stilt, the chicks are cared for by the parents for several months, and they may move them to new areas and defend territories there.<ref name=B&T/> Banded stilts deviate from this by collecting their chicks in massive crèches numbering several hundred.

Taxonomy

The taxonomy of the stilts is particularly debated, with the genus Himantopus considered to have two to six species.

Species in the family Recurvirostridae
Common and binomial names	Image	Range	Notes
Banded stilt Cladorhynchus leucocephalus	File:Banded stilts 2 Governors Lake Rotto email.jpg	southern Australia
Black-winged stilt Himantopus himantopus	File:Black-winged stilt (Himantopus himantopus).jpg	Europe, Asia and Africa	Sometimes includes pied (H. leucocephalus), white-backed (H. melanurus) and black-necked stilts (H. mexicanus) as subspecies
Pied stilt Himantopus (himantopus) leucocephalus	File:1 (83) Pied Stilt (Himantopus leucocephalus).JPG	Southeast Asia to Australia and New Zealand
White-backed stilt Himantopus (himantopus/mexicanus) melanurus	File:Himantopus melanurus 4.jpg	South America
Black-necked stilt Himantopus (himantopus) mexicanus	File:Black-necked Stilt (Himantopus mexicanus), Corte Madera.jpg	North America to northern South America, and Hawaii	Includes Hawaiian stilt (H. m. knudseni) and sometimes also white-backed stilt (H. melanurus) as subspecies
Black stilt Himantopus novaezelandiae	File:Himantopus-novaezelandiae.jpg	South Island of New Zealand
American avocet Recurvirostra americana	File:Recurvirostra americana -Palo Alto Baylands-8.jpg	North America
Andean avocet Recurvirostra andina	File:Recurvirostra andina.jpg	Andes in South America
Pied avocet Recurvirostra avosetta	File:Pied Avocet Recurvirostra avosetta.jpg	Europe, Asia and Africa
Red-necked avocet Recurvirostra novaehollandiae	File:Recurvirostra novaehollandiae in flight - Lake Joondalup.jpg	Australia

References

• Pierce, R.J. (1996) "Family Recurvirostridae (Stilts and Avocets) P.p. 332-348 in del Hoyo, J.; Elliot, A. & Sargatal, J. (editors). (1996). Handbook of the Birds of the World. Volume 3: Hoatzin to Auks. Lynx Edicions. Template:ISBN