Recurvirostridae is a family of
birdBirds are winged, bipedal, endothermic , vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the Bee Hummingbird to the ...
s in the
waderWaders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
suborder Charadrii. It contains two distinct groups of birds, the
avocetThe four species of Avocets are waders in the same avian family as the stilts. They are typically found in warm climates.Avocets have long legs and long, thin, upcurved bills which they sweep from side to side when feeding in the brackish or saline wetlands they prefer...
s (one genus) and the
stiltStilt is a common name for several species of birds in the family Recurvirostridae, which also includes those known as avocets. They are found in brackish or saline wetlands in warm or hot climates....
s (two genera).
Avocets and stilts range in length from and in weight from ; males are usually slightly bigger than females. 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.
Recurvirostridae is a family of
birdBirds are winged, bipedal, endothermic , vertebrate animals that lay eggs. There are around 10,000 living species, making them the most numerous tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Birds range in size from the Bee Hummingbird to the ...
s in the
waderWaders, called shorebirds in North America , are members of the order Charadriiformes, excluding the more marine web-footed seabird groups. The latter are the skuas , gulls , terns , skimmers , and auks...
suborder Charadrii. It contains two distinct groups of birds, the
avocetThe four species of Avocets are waders in the same avian family as the stilts. They are typically found in warm climates.Avocets have long legs and long, thin, upcurved bills which they sweep from side to side when feeding in the brackish or saline wetlands they prefer...
s (one genus) and the
stiltStilt is a common name for several species of birds in the family Recurvirostridae, which also includes those known as avocets. They are found in brackish or saline wetlands in warm or hot climates....
s (two genera).
Description and diet
Avocets and stilts range in length from and in weight from ; males are usually slightly bigger than females. 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, fully in avocets and the
Banded StiltThe Banded Stilt, Cladorhynchus leucocephalus, is a nomadic stilt from Australia. It gets its name from the red-brown breast band found on breeding adults, but this is mottled or entirely absent in non-breeding adults and juveniles. Its remaining plumage is pied and the eyes are dark brown...
, which swim more. The majority of species'
plumagePlumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage vary between species and subspecies and can also vary between different age classes, sexes, and season. Within species there can also be a...
has contrasting areas of black and white, with some species having patches of buff or brown on the head or chest. The sexes are similar.
Their vocalizations are usually yelps of one or two syllables.
These species feed on small aquatic animals such as mollusks,
brine shrimpBrine shrimp is the English name of the genus Artemia of aquatic crustaceans. Artemia, the only genus in the family Artemiidae, have evolved little since the Triassic period...
and other
crustaceanCrustaceans are a very large group of arthropods, comprising almost 52,000 described species , and are usually treated as a subphylum . They include various familiar animals, such as crabs, lobsters, crayfish, shrimp, krill and barnacles...
s, larval
insectInsects are arthropods, having a hard exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae. They are the most diverse group of animals on the planet and include more than a million species that are already described. Insects represent more than half of all...
s, segmented worms,
tadpoleA tadpole, polliwog , or pollywiggle is the wholly aquatic larval stage in the life cycle of an amphibian, particularly of a frog or toad.- Appellation :The name "tadpole" is from Middle English taddepol, made up of the elements tadde, "toad", and...
s, and small
fishA fish is any aquatic vertebrate animal that is typically ectothermic , covered with scales, and equipped with two sets of paired fins and several unpaired fins...
.
Distribution
Avocets and stilts are a
cosmopolitanIn biogeography, cosmopolitan distribution is a state of being found almost anywhere around the world. A cosmopolitan biological category, e.g. genus, may be called a cosmopolite.Examples of cosmopolitan species:* Humans* House dust mite...
family, being distributed on all the world's continents except Antarctica, and occurring on several oceanic islands. There are several wide-ranging species and a few locally distributed species.
One species, the
Black StiltThe Black Stilt or Kakī , Himantopus novaezelandiae, is a large wader in the avocet and stilt family Recurvirostridae. The species is endemic to New Zealand. Adults are 40 cm long. They have very long red legs, a long thin black bill and black plumage...
of
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses , and numerous smaller islands, most notably Stewart Island/Rakiura and the Chatham Islands. The indigenous Māori named New Zealand Aotearoa, commonly translated as The Land of the Long White Cloud...
, is
critically endangeredOrganisms with a conservation status of critically endangered have an extremely high risk of becoming extinct in the wild or completely extinct in the immediate future.-IUCN Category:...
due to habitat loss,
introduced predatorsAn introduced, alien, exotic, non-indigenous, or non-native species, or simply an introduction, is a species living outside its native distributional range, which has arrived there by human activity, either deliberate or accidental...
and hybridisation with the Pied Stilt.
Reproduction
Stilts and avocets breed on open ground near water, often in loose
coloniesA bird colony is used to refer to large aggregations of individuals of one or more species of bird that roost or nest in close proximity at a particular location...
. They defend nesting territories vigorously with aggressive displays and mob intruders and possible predators with a great deal of noise. They are
monogamousMonogamy is the state of having only one sexual partner at any one time. The word monogamy comes from the Greek word monos "μονός", which means one or alone, and the Greek word gamos "γάμος", which means marriage or union...
, although the pair bonds are not maintained from season to season. Their eggs are light-coloured with dark markings, weighing . Three to four are laid in simple
nestsA bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term is popular in reference to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
, and both parents share the
incubationIncubation is the process by which birds hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of sitting on eggs to incubate...
duties, which last 22 to 28 days. The Banded Stilt may breed only every couple of years, as it breeds on temporary lakes caused by rains in the deserts of Australia. The chicks are
downyThe down of birds is a layer of fine feathers found under the tougher exterior feathers. Very young birds are clad only in down. Powder down is a specialized type of down found only in a few groups of birds. Down is a fine thermal insulator and padding, used in goods such as jackets, bedding,...
and
precocialIn Biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching. The opposite developmental strategy is called "altricial," where the young are born helpless. Extremely precocial species may be called "superprecocial."...
, leaving the nest within a day of hatching; they fledge in 28 to 35 days. In all species except the Banded Stilt, the chicks are cared for several months by the parents, which may move them to new areas and defend territories there; Banded Stilts deviate from this by collecting their chicks in massive
crèchesThe Crèche in zoology refers to care of another's offspring, for instance in a colony. This term is used in the study of bird colonies...
numbering several hundred.
Species
The taxonomy of the stilts is particularly debated, with the genus
Himantopus considered to have two to six species.
FAMILY: RECURVIROSTRIDAE
- Genus: Recurvirostra - Avocets
- Pied Avocet
The Pied Avocet, Recurvirostra avosetta, is a large black and white wader in the avocet and stilt family, Recurvirostridae. They breed in temperate Europe and western and Central Asia. It is a migratory species and most winter in Africa or southern Asia...
, Recurvirostra avosetta
- American Avocet
The American Avocet is a large wader in the avocet and stilt family, Recurvirostridae.This avocet has long, thin, gray legs, giving it its colloquial name, "blue shanks". The plumage is black and white on the back with white on the underbelly. The neck and head are cinnamon colored in the summer...
, Recurvirostra americana
- Red-necked Avocet
The Red-necked Avocet is a water bird found throughout Australia, except for the northern parts of the Northern Territory....
, Recurvirostra novaehollandiae
- Andean Avocet
The Andean Avocet is a large wader in the avocet and stilt bird family, Recurvirostridae. It is resident in the Andes, breeding above 3500 m in northwestern Argentina, western Bolivia, northern Chile and southern Peru.-Description:...
, Recurvirostra andina
- Genus: Himantopus
- Black-winged Stilt
The Black-winged Stilt is a widely distributed very long-legged wader in the avocet and stilt family . Opinions differ as to whether the birds treated under the scientific name H. himantopus ought to be treated as a single species and if not, how many species to recognize...
, Himantopus himantopus
- Pied Stilt, Himantopus (himantopus) leucocephalus
- Hawaiian Stilt or aeʻo, Himantopus (himantopus/mexicanus) knudseni
- White-backed Stilt, Himantopus (himantopus/mexicanus) melanurus
- Black-necked Stilt
The Black-necked Stilt is a locally abundant shorebird of American wetlands and coastlines. It is found from the coastal areas of California through much of the interior western United States and along the Gulf of Mexico as far east as Florida, then south through Central America and the Caribbean...
, Himantopus (himantopus/mexicanus) mexicanus
- Black Stilt
The Black Stilt or Kakī , Himantopus novaezelandiae, is a large wader in the avocet and stilt family Recurvirostridae. The species is endemic to New Zealand. Adults are 40 cm long. They have very long red legs, a long thin black bill and black plumage...
, Himantopus novaezelandiae
- Genus: Cladorhynchus
- Banded Stilt
The Banded Stilt, Cladorhynchus leucocephalus, is a nomadic stilt from Australia. It gets its name from the red-brown breast band found on breeding adults, but this is mottled or entirely absent in non-breeding adults and juveniles. Its remaining plumage is pied and the eyes are dark brown...
, Cladorhynchus leucocephalus