Double-striped Thick-knee
Encyclopedia
The Double-striped Thick-knee, Burhinus bistriatus, is a Stone-curlew
, a group of wader
s in the family Burhinidae.
It is a resident breeder in Central
and South America
from southern Mexico
south to Colombia
, Venezuela
and northern Brazil
. It also occurs on Hispaniola
and some of the Venezuelan islands, and is a very rare vagrant
to Trinidad
, Curaçao
and the USA
.
This is a largely nocturnal
and crepuscular
species of arid grassland
, savanna
, and other dry, open habitats. The nest is a bare scrape into which two olive-brown eggs are laid and incubated by both adults for 25-27 days to hatching. The downy young are precocial and soon leave the nest.
The Double-striped Thick-knee is a medium-large wader with a strong black and yellow bill, large yellow eyes, which give it a reptilian appearance, and cryptic plumage. The scientific genus
name refers to the prominent joints in the long greenish-grey legs, and bistriatus to the two stripes of the head pattern.
The adult is about 46-50 cm long and weighs about 780-785 g. It has finely streaked grey-brown upperparts, and a paler brown neck and breast merging into the white belly. The head has a strong white supercilium bordered above by a black stripe. Juveniles are similar to adults, but have slightly darker brown upperparts and a whitish nape.
Double-striped Thick-knee is striking in flight, with a white patch on the dark upperwing, and a white underwing with a black rear edge. However, it avoids flying, relying on crouching and camouflage for concealment. The song, given at night, is a loud kee-kee-kee.
There are four subspecies, differing in size and plumage tone, but individual variation makes identification of races difficult.
The Double-striped Thick-knee eats large insect
s and other small vertebrate and invertebrate prey. It is sometimes semi-domestcated because of its useful function in controlling insects, and has benefited from the clearing of woodlands to create pasture.
Stone-curlew
The Stone-curlews, also known as Dikkops or Thick-knees are a group of largely tropical birds in the family Burhinidae. Despite the group being classified as waders, most species have a preference for arid or semi-arid habitats...
, a group of wader
Wader
Waders, 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...
s in the family Burhinidae.
It is a resident breeder in Central
Central America
Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
and South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
from southern Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
south to Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
, Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
and northern Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. It also occurs on Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
and some of the Venezuelan islands, and is a very rare vagrant
Vagrancy (biology)
Vagrancy is a phenomenon in biology whereby individual animals appear well outside their normal range; individual animals which exhibit vagrancy are known as vagrants. The term accidental is sometimes also used...
to Trinidad
Trinidad
Trinidad is the larger and more populous of the two major islands and numerous landforms which make up the island nation of Trinidad and Tobago. It is the southernmost island in the Caribbean and lies just off the northeastern coast of Venezuela. With an area of it is also the fifth largest in...
, Curaçao
Curaçao
Curaçao is an island in the southern Caribbean Sea, off the Venezuelan coast. The Country of Curaçao , which includes the main island plus the small, uninhabited island of Klein Curaçao , is a constituent country of the Kingdom of the Netherlands...
and the USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
This is a largely nocturnal
Nocturnal animal
Nocturnality is an animal behavior characterized by activity during the night and sleeping during the day. The common adjective is "nocturnal"....
and crepuscular
Crepuscular
Crepuscular animals are those that are active primarily during twilight, that is during dawn and dusk. The word is derived from the Latin word crepusculum, meaning "twilight." Crepuscular is, thus, in contrast with diurnal and nocturnal behavior. Crepuscular animals may also be active on a bright...
species of arid grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
, savanna
Savanna
A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently small or widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of C4 grasses.Some...
, and other dry, open habitats. The nest is a bare scrape into which two olive-brown eggs are laid and incubated by both adults for 25-27 days to hatching. The downy young are precocial and soon leave the nest.
The Double-striped Thick-knee is a medium-large wader with a strong black and yellow bill, large yellow eyes, which give it a reptilian appearance, and cryptic plumage. The scientific genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
name refers to the prominent joints in the long greenish-grey legs, and bistriatus to the two stripes of the head pattern.
The adult is about 46-50 cm long and weighs about 780-785 g. It has finely streaked grey-brown upperparts, and a paler brown neck and breast merging into the white belly. The head has a strong white supercilium bordered above by a black stripe. Juveniles are similar to adults, but have slightly darker brown upperparts and a whitish nape.
Double-striped Thick-knee is striking in flight, with a white patch on the dark upperwing, and a white underwing with a black rear edge. However, it avoids flying, relying on crouching and camouflage for concealment. The song, given at night, is a loud kee-kee-kee.
There are four subspecies, differing in size and plumage tone, but individual variation makes identification of races difficult.
The Double-striped Thick-knee eats large insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s and other small vertebrate and invertebrate prey. It is sometimes semi-domestcated because of its useful function in controlling insects, and has benefited from the clearing of woodlands to create pasture.
External links
- Double-striped Thick-knee videos on the Internet Bird Collection
- Photo-Medium Res; Article sunbirdtours
- Photo-High Res-(display); Article borderland-tours Photo2-(display)
- Double-striped Thick-knee photo gallery VIREO Photo-High Res
