Chlidonias niger

Taxonomy

Assessment Information

Geographic Range

Habitat and Ecology

Threats

View Printer Friendly

Taxonomy [top]

Kingdom	Phylum	Class	Order	Family
ANIMALIA	CHORDATA	AVES	CHARADRIIFORMES	LARIDAE

Scientific Name:

Chlidonias niger

Species Authority:

(Linnaeus, 1758)

Common Name/s:

English	–	Black Tern
French	–	Guifette noire

Assessment Information [top]

Red List Category & Criteria:

Least Concern ver 3.1

Year Assessed:

2009

Assessor/s:

BirdLife International

Reviewer/s:

Bird, J., Butchart, S.

Justification:
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

History:

2008	–	Least Concern
2004	–	Least Concern

Geographic Range [top]

Range Description:	The Black Tern is found in the Old and New World. It ranges from southern Scandinavia to southern Spain, east through Europe and western Asia to central Mongolia. Individuals from this area predominately winter on the Atlantic coast of Africa, from the Western Sahara to South Africa. It is also found across much of Canada to northern regions of the USA, with individuals wintering on the Pacific coast of Mexico, the Pacific and Atalantic coast of Central America and northern South America¹.
Countries:	Native: Albania; Algeria; Angola; Anguilla; Antigua and Barbuda; Argentina; Armenia; Aruba; Austria; Azerbaijan; Bahamas; Barbados; Belarus; Belgium; Belize; Benin; Bermuda; Bosnia and Herzegovina; Brazil; Bulgaria; Cameroon; Canada; Cayman Islands; Chile; China; Colombia; Congo; Costa Rica; Côte d'Ivoire; Croatia; Cuba; Cyprus; Czech Republic; Denmark; Djibouti; Dominica; Dominican Republic; Ecuador; Egypt; El Salvador; Equatorial Guinea; Eritrea; Estonia; Ethiopia; Finland; France; French Guiana; Gabon; Gambia; Georgia; Germany; Ghana; Gibraltar; Greece; Guatemala; Guinea; Guinea-Bissau; Guyana; Haiti; Honduras; Hungary; India; Iran, Islamic Republic of; Ireland; Israel; Italy; Jamaica; Jordan; Kazakhstan; Kyrgyzstan; Latvia; Liberia; Libyan Arab Jamahiriya; Liechtenstein; Lithuania; Luxembourg; Macedonia, the former Yugoslav Republic of; Mali; Malta; Martinique; Mauritania; Mexico; Moldova; Mongolia; Montenegro; Montserrat; Morocco; Namibia; Netherlands; Netherlands Antilles; Nicaragua; Nigeria; Palestinian Territory, Occupied; Panama; Peru; Poland; Portugal; Puerto Rico; Romania; Russian Federation; Russian Federation; Russian Federation; Saint Kitts and Nevis; Saint Lucia; Saint Pierre and Miquelon; Saint Vincent and the Grenadines; Senegal; Serbia; Sierra Leone; Slovakia; Slovenia; South Africa; Spain; Sri Lanka; Suriname; Sweden; Switzerland; Syrian Arab Republic; Tajikistan; Tanzania, United Republic of; Togo; Trinidad and Tobago; Tunisia; Turkey; Turkmenistan; Turks and Caicos Islands; Ukraine; United Kingdom; United States; Uzbekistan; Venezuela; Western Sahara Vagrant: Afghanistan; Australia; Bahrain; Chad; Congo, The Democratic Republic of the; Grenada; Guadeloupe; Iceland; Iraq; Japan; Kenya; Kuwait; Lebanon; Madagascar; Niger; Oman; Rwanda; Saudi Arabia; Somalia; Sudan; United Arab Emirates; Uruguay; Virgin Islands, British; Virgin Islands, U.S.; Yemen Present - origin uncertain: Sao Tomé and Principe
Range Map:	Click here to open the map viewer and explore range.

Habitat and Ecology [top]

Habitat and Ecology:	Behaviour This species is strongly migratory¹ and travels both over land and over sea⁴. It breeds between May and June¹ in colonies, usually of less than 20 pairs (rarely more than 100 pairs)¹ and often close to other species^{3, 4}. After breeding it departs for its wintering grounds from July onwards², returning north again from late-March⁴. The species is gregarious throughout the year⁴, foraging in groups of 2-20 during the breeding season and congregating in large flocks offshore on passage and in the winter over shoals of predatory fish^{1, 2, 4}. Habitat Breeding The species breeds on fresh or brackish wetlands² such as small pools, lakes, marshes^{1, 2}, ditches, overgrown canals, quiet reaches of rivers, swampy meadows², peat bogs and rice-fields¹, showing a preference for well-vegetated areas¹ with sparse, open emergent vegetation¹ (e.g. Typha spp., sedge or reeds)³ and floating water-lilies¹, and with water 1-2 m deep¹. It generally avoids small marshland areas less than 4 ha in area¹. Non-breeding On passage the species frequents inland wetlands including pools, ditches¹, reservoirs, lakes and sewage farms⁴, as well as coastal habitats and estuaries¹. In winter it is predominantly coastal however, frequenting estuaries^{1, 4}, saltmarshes, bays⁴, coastlines and coastal lagoons¹ as well as marine waters up to 400-600 km offshore⁵. Diet Breeding Its breeding diet consists predominantly of insects (e.g. chironomids, Odonata, Ephemeroptera and Coleoptera) as well as small fish¹ and amphibians⁴ (e.g. tadpoles and frogs)¹. Non-breeding On passage and during the winter the species's diet consists largely of marine fish although insects and crustaceans may also be taken⁴. Breeding site The nest may be a low compressed mound of plant matter^{3, 4} placed in very shallow water⁴ or on a floating mat of aquatic vegetation³ over water more than 50 cm deep¹. The nest may also be a shallow scrape⁴ on the ground amongst marsh vegetation⁴. The species breeds in small colonies and may forage up to 2-5 km from breeding sites¹. Management information In the Netherlands the provision of anchored artificial nesting rafts has been partly successful as a conservation measure^{7, 8}, especially in habitats where unstable nest substrates (such as floating water-lilies) result in poor breeding successes⁸. In the Netherlands there have also been successful programmes to reduce disturbance and improve habitat quality in agricultural areas, which has benefited the species⁷. The application of glyphosphate-based herbicides to combat and prevent the overgrowth of Typha spp. in wetlands may also benefit the species¹¹.
Systems:	Terrestrial; Freshwater; Marine

Habitat and Ecology:

Behaviour This species is strongly migratory¹ and travels both over land and over sea⁴. It breeds between May and June¹ in colonies, usually of less than 20 pairs (rarely more than 100 pairs)¹ and often close to other species^{3, 4}. After breeding it departs for its wintering grounds from July onwards², returning north again from late-March⁴. The species is gregarious throughout the year⁴, foraging in groups of 2-20 during the breeding season and congregating in large flocks offshore on passage and in the winter over shoals of predatory fish^{1, 2, 4}. Habitat Breeding The species breeds on fresh or brackish wetlands² such as small pools, lakes, marshes^{1, 2}, ditches, overgrown canals, quiet reaches of rivers, swampy meadows², peat bogs and rice-fields¹, showing a preference for well-vegetated areas¹ with sparse, open emergent vegetation¹ (e.g. Typha spp., sedge or reeds)³ and floating water-lilies¹, and with water 1-2 m deep¹. It generally avoids small marshland areas less than 4 ha in area¹. Non-breeding On passage the species frequents inland wetlands including pools, ditches¹, reservoirs, lakes and sewage farms⁴, as well as coastal habitats and estuaries¹. In winter it is predominantly coastal however, frequenting estuaries^{1, 4}, saltmarshes, bays⁴, coastlines and coastal lagoons¹ as well as marine waters up to 400-600 km offshore⁵. Diet Breeding Its breeding diet consists predominantly of insects (e.g. chironomids, Odonata, Ephemeroptera and Coleoptera) as well as small fish¹ and amphibians⁴ (e.g. tadpoles and frogs)¹. Non-breeding On passage and during the winter the species's diet consists largely of marine fish although insects and crustaceans may also be taken⁴. Breeding site The nest may be a low compressed mound of plant matter^{3, 4} placed in very shallow water⁴ or on a floating mat of aquatic vegetation³ over water more than 50 cm deep¹. The nest may also be a shallow scrape⁴ on the ground amongst marsh vegetation⁴. The species breeds in small colonies and may forage up to 2-5 km from breeding sites¹. Management information In the Netherlands the provision of anchored artificial nesting rafts has been partly successful as a conservation measure^{7, 8}, especially in habitats where unstable nest substrates (such as floating water-lilies) result in poor breeding successes⁸. In the Netherlands there have also been successful programmes to reduce disturbance and improve habitat quality in agricultural areas, which has benefited the species⁷. The application of glyphosphate-based herbicides to combat and prevent the overgrowth of Typha spp. in wetlands may also benefit the species¹¹.

Systems:

Terrestrial; Freshwater; Marine

Threats [top]

Major Threat(s):	On its breeding grounds the species is threatened by reductions in food availability due to the eutrophication of surface waters (which reduces the diversity of large insects)¹⁰, the acidification of lakes (which leads to the death of fish)¹⁰, the introduction of exotic fish species (e.g. peacock bass Cichla ocellaris)¹ and pesticide pollution (which may also lead to direct mortality from poisoning)¹. When breeding the species is also threatened by fluctuating water levels⁴, the loss and deterioration of freshwater nesting habitats^{1, 7} (e.g. through drainage for agriculture^{1, 4} and overgrowth of Typha spp. beds¹, 11), and human disturbance^{1, 4, 7} (especially where this forces breeding pairs to leave the nest before the young are fully fledged)⁹. The species is also susceptible to avian influenza so may be threatened by future outbreaks of the virus⁶.

Major Threat(s):

On its breeding grounds the species is threatened by reductions in food availability due to the eutrophication of surface waters (which reduces the diversity of large insects)¹⁰, the acidification of lakes (which leads to the death of fish)¹⁰, the introduction of exotic fish species (e.g. peacock bass Cichla ocellaris)¹ and pesticide pollution (which may also lead to direct mortality from poisoning)¹. When breeding the species is also threatened by fluctuating water levels⁴, the loss and deterioration of freshwater nesting habitats^{1, 7} (e.g. through drainage for agriculture^{1, 4} and overgrowth of Typha spp. beds¹, 11), and human disturbance^{1, 4, 7} (especially where this forces breeding pairs to leave the nest before the young are fully fledged)⁹. The species is also susceptible to avian influenza so may be threatened by future outbreaks of the virus⁶.

Citation:	BirdLife International 2009. Chlidonias niger. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. <www.iucnredlist.org>. Downloaded on 07 February 2012.
Disclaimer:	To make use of this information, please check the <Terms of Use>.
Feedback:	If you see any errors or have any questions or suggestions on what is shown on this page, please fill in the feedback form so that we can correct or extend the information provided