Nutcracker (talk | contribs) (more details) |
|||
| Line 1: | Line 1: | ||
| − | [[Image: | + | [[Image:1321 zwstern.jpg|thumb|550px|right|''C. n. niger'', adult summer<br /> Photo by {{user|Mirage|Mirage}}<br />Netherlands, June 2007]] |
;[[:Category:Chlidonias|Chlidonias]] niger | ;[[:Category:Chlidonias|Chlidonias]] niger | ||
==Identification== | ==Identification== | ||
| − | '''Breeding''' ( | + | *'''Breeding''' (April - July): Black head, breast and belly. Uniform grey back, wings and rump/tail. White undertail. Bill black. Dark legs. |
| − | + | *'''Non-breeding''': Underparts white, grey above. Falcon-like black hood. Characteristic black (or dark brown) line above shoulder, extending onto outer edges of breast. Legs orange/red. Bill black. Tail off-white with grey rump and upper tail coverts (white in [[White-winged Tern]] ''Chlidonias leucopterus''). | |
| − | '''Non-breeding''': Underparts white, grey above. Falcon-like black hood. Characteristic black (or dark brown) line above shoulder, extending onto outer edges of breast. Legs orange/red. Bill black. Tail off-white with grey rump and upper tail coverts (white in [[White-winged Tern]] ''Chlidonias leucopterus''). | + | *'''Juvenile''': Like non-breeding adult but with darker back feathers and coverts with distinct buff/lighter edges. |
| − | + | [[Image:Chlidonias niger niger by Cristian Mihai.jpg|thumb|350px|right|''C. n. niger'', juvenile plumage - white flanks.<br />{{user|Cristian Mihai|Cristian Mihai}} <br />Vadu, [[Romania]]; August 2014 ]] | |
| − | '''Juvenile''': Like non-breeding adult but with distinct buff/lighter edges | + | [[Image:Chlidonias niger surinamensis by targetman.jpg|thumb|350px|right|''C. n. surinamensis'', juvenile plumage - grey flanks.<br />{{user|targetman|targetman}} <br />vagrant, Covenham Reservoir, Lincolnshire, UK; September 2011. ]] |
| − | [[Image: | + | ====Similar species==== |
| + | See [[White-winged Tern]] for differences. | ||
==Distribution== | ==Distribution== | ||
| − | + | Breeds in wetlands in central and eastern [[Europe]], western [[Asia]], and central [[North America]]. Winters mainly at sea, also on larger lakes and rivers, on the west coast of [[Africa]] and both coasts of [[Central America]] and northern [[South America]]. | |
==Taxonomy== | ==Taxonomy== | ||
====Subspecies==== | ====Subspecies==== | ||
| − | + | There are two subspecies<sup>[[#References|[1]]]</sup>: | |
*''C. n. niger'' (Eurasian): | *''C. n. niger'' (Eurasian): | ||
| − | : | + | ::Breeds central and eastern Europe and western Asia; winters in Africa. Vagrant northwest to Iceland. |
*''C. n. surinamensis'' (North American): | *''C. n. surinamensis'' (North American): | ||
| − | : | + | ::Breeds North America; winters Central America and northern South America. A rare vagrant to western Europe. |
| + | |||
| + | The two subspecies are very similar in breeding plumage; the most useful distinction is that the underwing of ''C. n. niger'' is dusky grey, while the underwing of ''C. n. surinamensis'' is white. <br>In winter and juvenile plumages, both have a white underwing, but the head and flank patters differ more obviously; ''C. n. niger'' has a sharply defined black crown, a narrow black 'peg' on the side of the neck, and white flanks, while ''C. n. surinamensis'' has a diffusely defined grey rear crown, a broad, diffuse grey-brown 'peg' on the side of the neck, and dusky grey flanks (see photos, right, for comparison). | ||
| + | |||
| + | A few authors have suggested they might be better treated as separate species, but none of the major authorities have taken this up at the moment. | ||
| + | |||
==Habitat== | ==Habitat== | ||
| − | Freshwater lakes, gravel pits and reservoirs, marshes, wet grassland, | + | Freshwater lakes, gravel pits and reservoirs, marshes, wet grassland; in winter on sea coasts and estuaries, and occasionally large lakes. |
| − | + | ||
| − | |||
| − | |||
==Behaviour== | ==Behaviour== | ||
| + | [[Image:North American Black Tern.jpg|thumb|350px|right|''C. n. surinamensis'', juvenile plumage.<br />{{user|Dmitry+Mozzheri|Dmitry Mozzheri}} <br />Long Island, [[New York]] ]] | ||
====Diet==== | ====Diet==== | ||
| − | The diet includes insects, invertebrates and fish. | + | The diet includes insects, invertebrates and small fish. |
====Breeding==== | ====Breeding==== | ||
The nest is usually floating vegetation in shallow water (possibly on the ground close to water). The clutch consists of 2-4 eggs which are incubated for 21-22 days. The young fledge after 19-25 days. | The nest is usually floating vegetation in shallow water (possibly on the ground close to water). The clutch consists of 2-4 eggs which are incubated for 21-22 days. The young fledge after 19-25 days. | ||
Revision as of 17:21, 9 November 2014
- Chlidonias niger
Identification
- Breeding (April - July): Black head, breast and belly. Uniform grey back, wings and rump/tail. White undertail. Bill black. Dark legs.
- Non-breeding: Underparts white, grey above. Falcon-like black hood. Characteristic black (or dark brown) line above shoulder, extending onto outer edges of breast. Legs orange/red. Bill black. Tail off-white with grey rump and upper tail coverts (white in White-winged Tern Chlidonias leucopterus).
- Juvenile: Like non-breeding adult but with darker back feathers and coverts with distinct buff/lighter edges.
C. n. surinamensis, juvenile plumage - grey flanks.
targetman
vagrant, Covenham Reservoir, Lincolnshire, UK; September 2011.
targetman
vagrant, Covenham Reservoir, Lincolnshire, UK; September 2011.
Similar species
See White-winged Tern for differences.
Distribution
Breeds in wetlands in central and eastern Europe, western Asia, and central North America. Winters mainly at sea, also on larger lakes and rivers, on the west coast of Africa and both coasts of Central America and northern South America.
Taxonomy
Subspecies
There are two subspecies[1]:
- C. n. niger (Eurasian):
- Breeds central and eastern Europe and western Asia; winters in Africa. Vagrant northwest to Iceland.
- C. n. surinamensis (North American):
- Breeds North America; winters Central America and northern South America. A rare vagrant to western Europe.
The two subspecies are very similar in breeding plumage; the most useful distinction is that the underwing of C. n. niger is dusky grey, while the underwing of C. n. surinamensis is white.
In winter and juvenile plumages, both have a white underwing, but the head and flank patters differ more obviously; C. n. niger has a sharply defined black crown, a narrow black 'peg' on the side of the neck, and white flanks, while C. n. surinamensis has a diffusely defined grey rear crown, a broad, diffuse grey-brown 'peg' on the side of the neck, and dusky grey flanks (see photos, right, for comparison).
A few authors have suggested they might be better treated as separate species, but none of the major authorities have taken this up at the moment.
Habitat
Freshwater lakes, gravel pits and reservoirs, marshes, wet grassland; in winter on sea coasts and estuaries, and occasionally large lakes.
Behaviour
Diet
The diet includes insects, invertebrates and small fish.
Breeding
The nest is usually floating vegetation in shallow water (possibly on the ground close to water). The clutch consists of 2-4 eggs which are incubated for 21-22 days. The young fledge after 19-25 days.
Vocalisation
<flashmp3>Chlidonias niger (song).mp3</flashmp3>
Listen in an external program
References
- Clements, JF. 2011. The Clements Checklist of Birds of the World. 6th ed., with updates to August 2011. Ithaca: Cornell Univ. Press. ISBN 978-0801445019. Spreadsheet available at http://www.birds.cornell.edu/clementschecklist/downloadable-clements-checklist
- Lepage D. 2008. Avibase. Search for "Black Tern" downloaded 29 April 2008.
- Wikipedia
Recommended Citation
- BirdForum Opus contributors. (2024) Black Tern. In: BirdForum, the forum for wild birds and birding. Retrieved 4 May 2024 from https://www.birdforum.net/opus/Black_Tern
External Links
