Black Turnstone
Encyclopedia
The Black Turnstone is a species of small wading
bird
. It is one of two species of turnstone
in the genus
Arenaria, the Ruddy Turnstone
(A. interpres) being the other. It is now classified in the sandpiper family Scolopacidae
but was formerly sometimes placed in the plover family Charadriidae
. It is native to the west coast of North America
and breeds only in Alaska
.
is 20-27 millimeters long and slightly upturned. The legs and feet are blackish-brown with a reddish tinge. The bird is largely black and white in appearance. Breeding-plumaged adults have a black head and breast apart from a white spot between the eye and bill, a white stripe over the eye and white flecks on the sides of the breast. The upperparts are blackish-brown with pale fringes to the wing-coverts and scapular feathers. The belly and vent are white. In flight it shows a white wingbar, white shoulder patch and white tail with a broad black band across it. There is white from the lower back to the uppertail-coverts apart from a dark bar across the rump.
In winter the head and breast become largely dark brown with little white. Juveniles
are similar to winter adults but browner with buff fringes to the wing-coverts and scapulars and a grey-brown tip to the tail.
The Ruddy Turnstone is similar but has rufous-brown markings on the upperparts and more white on the head and breast, particularly in breeding plumage. It has narrower wings and a narrower white wingbar. Its legs are orange and brighter than those of the Black Turnstone though there can be some overlap.
The Black Turnstone has a variety of calls, especially a rattling trill which can be heard throughout the year. This call is higher and less harsh than the similar call of the Ruddy Turnstone. Other calls include a loud, screeching alarm call and a soft, purring call uttered to young chicks. Displaying males produce a long series of staccato notes in flight as well as chirruping trills on the ground.
in the south to Point Hope
in the north. The bulk of the population nests in the Yukon-Kuskokwim Delta
. It usually nests near the coast but in some areas it occurs further inland along the shores of rivers and lakes. There are a handful of records from north-east Siberia
but there has been no sign of breeding there. The world population is estimated at 95,000 birds with about 80,000 of these in the Yukon-Kuskokwim Delta.
It winters on rocky shores along the Pacific coast of North America from southern Alaska southwards as far as north-west Mexico
where it occurs in Baja California
and Sonora
with a single record from Nayarit
. It is very occasionally seen inland during spring and fall migration; there are a number of records from the Salton Sea
in southern California
and scattered sightings from inland US states including Montana
, Wisconsin
, Nevada
and Arizona
. Vagrant birds have been recorded from Yukon
and the Northwest Territories
and there is one record from San Cristóbal Island
in the Galápagos Islands
.
s and mollusks in winter and insect
s during the breeding season. Seeds, eggs and carrion are also taken. At the breeding grounds it mainly feeds in wet meadows with sedge
s. In winter, its typical habitat is rocky coasts but it also feeds on beaches, mudflats and man-made structures such as jetties and breakwaters. It uses its bill to turn over stones, algal mats and other objects to get at prey hidden beneath.
It arrives on its breeding ground from early May to early June with the males arriving first. The birds often return to the same territory and pair with the same mate as previous years. The nest
is a scrape dug mainly by the male. It is usually located amongst sedges or grasses or under willow
s. Four eggs
are usually laid; they are olive or pale greenish with darker spots. The eggs are incubated
for 21–24 days by both parents. The young birds are precocial
and are able to leave the nest and feed themselves soon after hatching. They are able to fly well after 25–34 days.
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...
bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
. It is one of two species of turnstone
Turnstone
Turnstones are the bird species in the genus Arenaria in the family Scolopacidae. They are closely related to calidrid sandpipers and might be considered members of the tribe Calidriini....
in the 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...
Arenaria, the Ruddy Turnstone
Ruddy Turnstone
The Ruddy Turnstone is a small wading bird, one of two species of turnstone in the genus Arenaria. It is now classified in the sandpiper family Scolopacidae but was formerly sometimes placed in the plover family Charadriidae...
(A. interpres) being the other. It is now classified in the sandpiper family Scolopacidae
Scolopacidae
The sandpipers are a large family, Scolopacidae, of waders or shorebirds. They include many species called sandpipers, as well as those called by names such as curlew and snipe. The majority of these species eat small invertebrates picked out of the mud or soil...
but was formerly sometimes placed in the plover family Charadriidae
Charadriidae
The bird family Charadriidae includes the plovers, dotterels, and lapwings, about 64 to 66 species in all.- Morphology :They are small to medium-sized birds with compact bodies, short, thick necks and long, usually pointed, wings, but most species of lapwing may have more rounded wings...
. It is native to the west coast of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and breeds only in Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
.
Description
It is 22-25 centimeters long and weighs 100-170 grams. The black billBeak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
is 20-27 millimeters long and slightly upturned. The legs and feet are blackish-brown with a reddish tinge. The bird is largely black and white in appearance. Breeding-plumaged adults have a black head and breast apart from a white spot between the eye and bill, a white stripe over the eye and white flecks on the sides of the breast. The upperparts are blackish-brown with pale fringes to the wing-coverts and scapular feathers. The belly and vent are white. In flight it shows a white wingbar, white shoulder patch and white tail with a broad black band across it. There is white from the lower back to the uppertail-coverts apart from a dark bar across the rump.
In winter the head and breast become largely dark brown with little white. Juveniles
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
are similar to winter adults but browner with buff fringes to the wing-coverts and scapulars and a grey-brown tip to the tail.
The Ruddy Turnstone is similar but has rufous-brown markings on the upperparts and more white on the head and breast, particularly in breeding plumage. It has narrower wings and a narrower white wingbar. Its legs are orange and brighter than those of the Black Turnstone though there can be some overlap.
The Black Turnstone has a variety of calls, especially a rattling trill which can be heard throughout the year. This call is higher and less harsh than the similar call of the Ruddy Turnstone. Other calls include a loud, screeching alarm call and a soft, purring call uttered to young chicks. Displaying males produce a long series of staccato notes in flight as well as chirruping trills on the ground.
Distribution
It breeds in western Alaska from the Alaska PeninsulaAlaska Peninsula
The Alaska Peninsula is a peninsula extending about to the southwest from the mainland of Alaska and ending in the Aleutian Islands. The peninsula separates the Pacific Ocean from Bristol Bay, an arm of the Bering Sea....
in the south to Point Hope
Point Hope, Alaska
Point Hope is a city in North Slope Borough, Alaska, United States. At the 2000 census the population was 757.-Geography:...
in the north. The bulk of the population nests in the Yukon-Kuskokwim Delta
Yukon-Kuskokwim Delta
The Yukon–Kuskokwim Delta is one of the largest river deltas in the world, roughly the size of Oregon. It is located where the Yukon and Kuskokwim rivers empty into the Bering Sea on the west coast of the U.S. state of Alaska. The delta, which mostly consists of tundra, is protected as part of the...
. It usually nests near the coast but in some areas it occurs further inland along the shores of rivers and lakes. There are a handful of records from north-east Siberia
Siberia
Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
but there has been no sign of breeding there. The world population is estimated at 95,000 birds with about 80,000 of these in the Yukon-Kuskokwim Delta.
It winters on rocky shores along the Pacific coast of North America from southern Alaska southwards as far as north-west 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...
where it occurs in Baja California
Baja California
Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...
and Sonora
Sonora
Sonora officially Estado Libre y Soberano de Sonora is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided into 72 municipalities; the capital city is Hermosillo....
with a single record from Nayarit
Nayarit
Nayarit officially Estado Libre y Soberano de Nayarit is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is divided in 20 municipalities and its capital city is Tepic.It is located in Western Mexico...
. It is very occasionally seen inland during spring and fall migration; there are a number of records from the Salton Sea
Salton Sea
The Salton Sea is a shallow, saline, endorheic rift lake located directly on the San Andreas Fault, predominantly in California's Imperial Valley. The lake occupies the lowest elevations of the Salton Sink in the Colorado Desert of Imperial and Riverside counties in Southern California. Like Death...
in southern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
and scattered sightings from inland US states including Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
, Wisconsin
Wisconsin
Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
, Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
and Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
. Vagrant birds have been recorded from Yukon
Yukon
Yukon is the westernmost and smallest of Canada's three federal territories. It was named after the Yukon River. The word Yukon means "Great River" in Gwich’in....
and the Northwest Territories
Northwest Territories
The Northwest Territories is a federal territory of Canada.Located in northern Canada, the territory borders Canada's two other territories, Yukon to the west and Nunavut to the east, and three provinces: British Columbia to the southwest, and Alberta and Saskatchewan to the south...
and there is one record from San Cristóbal Island
San Cristóbal Island
San Cristóbal is the easternmost island in the Galápagos archipelago, and one of the oldest geologically.Its Spanish name "San Cristóbal" comes from the patron saint of seafarers, St. Christopher...
in the Galápagos Islands
Galápagos Islands
The Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
.
Ecology
It feeds mainly on invertebrates, particularly crustaceanCrustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s and mollusks in winter and 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 during the breeding season. Seeds, eggs and carrion are also taken. At the breeding grounds it mainly feeds in wet meadows with sedge
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...
s. In winter, its typical habitat is rocky coasts but it also feeds on beaches, mudflats and man-made structures such as jetties and breakwaters. It uses its bill to turn over stones, algal mats and other objects to get at prey hidden beneath.
It arrives on its breeding ground from early May to early June with the males arriving first. The birds often return to the same territory and pair with the same mate as previous years. The nest
Bird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers 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...
is a scrape dug mainly by the male. It is usually located amongst sedges or grasses or under willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
s. Four eggs
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
are usually laid; they are olive or pale greenish with darker spots. The eggs are incubated
Avian incubation
Incubation refers to the process by which certain oviparous animals 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...
for 21–24 days by both parents. The young birds are precocial
Precocial
In 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 or hatched helpless. Extremely precocial species may be called...
and are able to leave the nest and feed themselves soon after hatching. They are able to fly well after 25–34 days.