Black Skimmer
Encyclopedia
The Black Skimmer, Rynchops niger, is a tern
Tern
Terns are seabirds in the family Sternidae, previously considered a subfamily of the gull family Laridae . They form a lineage with the gulls and skimmers which in turn is related to skuas and auks...

-like seabird
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...

, one of three very similar birds species in the skimmer
Skimmer
The Skimmers, Rynchopidae, are a small family of tern-like birds in the order Charadriiformes, which also includes the waders, gulls and auks. The family comprises three species found in South Asia, Africa, and the Americas....

 family. It breeds in North
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 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...

. Northern populations winter
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...

 in the warmer waters of the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...

 and the tropical and subtropical Pacific coasts, but the South American races make only shorter movements in response to annual floods which extend their feeding areas in the river shallows.

The Black Skimmer breeds in loose groups on sandbanks and sandy beaches in the Americas, the three to seven heavily dark-blotched buff or bluish eggs being incubated by both the male and female. The chicks leave the nest as soon as they hatch and lie inconspicuously in the nest depression or "scrape" where they are shaded from high temperatures by the parents. They may dig their own depressions in the sand at times. Parents feed the young almost exclusively during the day with almost no feeding occurring at night, due to the entire population of adults sometimes departing the colony to forage. Although the mandibles are of equal length at hatching, they rapidly become unequal during fledging.

The Black Skimmer is the largest of the three skimmer species. It measures 40 – long with a 107 – wingspan. This species ranges from 212 to 447 g (7.5 to 15.8 oz), with males averaging about 349 g (12.3 oz), as compared to the smaller female’s 254 g (9 oz). The basal half of the bill is red, the rest mainly black, and the lower mandible is much-elongated. The eye has a dark brown iris and cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...

like vertical pupil, unique for a bird. The legs are red. The call is a barking kak-kak-kak.

Adults in breeding plumage have a black crown, nape and upper body. The forehead and underparts are white. The upper wings are black with white on the rear edge, and the tail and rump are dark grey with white edges. The underwing colour varies from white to dusky grey depending on region.
Non-breeding adults have paler and browner upperparts, and a white nape collar. Immature birds have brown upperparts with white feather tips and fringes. The underparts and forehead are white, and the underwings as the adult.

The Black Skimmer has three subspecies:
  • Migratory R. n. niger breeds on the Atlantic coast of North America, and from 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...

     to Ecuador
    Ecuador
    Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...

     in the Pacific.
  • R. n. cinerescens is larger, has dusky underwings, and only a narrow white fringe to its black tail, and breeds in northern and northeastern South America and the Amazon basin
    Amazon Basin
    The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...

    .
  • R. n. intercedens occurs on the rest of the Atlantic coast of South America south to central Argentina
    Argentina
    Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

    .


Skimmers have a light graceful flight, with steady beats of their long wings. They feed usually in large flocks, flying low over the water surface with the lower mandible skimming the water (in order of importance) for small fish, 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, crustacean
Crustacean
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 molluscs caught by touch by day or especially at night. They spend much time loafing gregariously on sandbars in the rivers, coasts and lagoons they frequent.

External links

  • Black Skimmer videos on the Internet Bird Collection
  • Field Guide on Flickr
  • Stamps (for Antigua
    Antigua
    Antigua , also known as Waladli, is an island in the West Indies, in the Leeward Islands in the Caribbean region, the main island of the country of Antigua and Barbuda. Antigua means "ancient" in Spanish and was named by Christopher Columbus after an icon in Seville Cathedral, Santa Maria de la...

    , 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...

    , Nevis
    Nevis
    Nevis is an island in the Caribbean Sea, located near the northern end of the Lesser Antilles archipelago, about 350 km east-southeast of Puerto Rico and 80 km west of Antigua. The 93 km² island is part of the inner arc of the Leeward Islands chain of the West Indies...

    , Nicaragua
    Nicaragua
    Nicaragua is the largest country in the Central American American isthmus, bordered by Honduras to the north and Costa Rica to the south. The country is situated between 11 and 14 degrees north of the Equator in the Northern Hemisphere, which places it entirely within the tropics. The Pacific Ocean...

    , Uruguay
    Uruguay
    Uruguay ,officially the Oriental Republic of Uruguay,sometimes the Eastern Republic of Uruguay; ) is a country in the southeastern part of South America. It is home to some 3.5 million people, of whom 1.8 million live in the capital Montevideo and its metropolitan area...

    ) with RangeMap
  • Black Skimmer photo galley VIREO
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