Sternula antillarum 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Charadriiformes Laridae

Scientific Name: Sternula antillarum
Species Authority: Lesson, 1847
Common Name(s):
English Least Tern
Sterna antillarum (Lesson, 1847)
Sternula antillarum AOU checklist (1998 + supplements)
Taxonomic Source(s): del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Lynx Edicions BirdLife International.
Taxonomic Notes: Sternula antillarum (del Hoyo and Collar 2014) was previously placed in the genus Sterna.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Facilitator/Compiler(s): Butchart, S., Calvert, R. & Ekstrom, J.
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.
Previously published Red List assessments:
2009 Least Concern (LC)
2008 Least Concern (LC)
2004 Least Concern (LC)
2000 Lower Risk/least concern (LR/lc)
1994 Lower Risk/least concern (LR/lc)
1988 Lower Risk/least concern (LR/lc)

Geographic Range [top]

Range Description: The Least Tern breeds along almost the entire coast of North America, excluding Alaska and Canada, on the northern coast of Central America and locally on the northern coast of South America. It also breeds inland along rivers in central North America. It is migratory, wintering on the southern coast of Central America, and the northern and Atlantic coast of South America as far south as central Brazil (del Hoyo et al. 1996).

Countries occurrence:
Anguilla; Antigua and Barbuda; Argentina; Aruba; Bahamas; Barbados; Belize; Bonaire, Sint Eustatius and Saba (Saba, Sint Eustatius); Brazil; Canada; Cayman Islands; Colombia; Costa Rica; Cuba; Curaçao; Dominica; Dominican Republic; El Salvador; French Guiana; Guadeloupe; Guatemala; Guyana; Haiti; Honduras; Jamaica; Martinique; Mexico; Montserrat; Panama; Peru; Puerto Rico; Saint Kitts and Nevis; Saint Lucia; Saint Martin (French part); Saint Vincent and the Grenadines; Sint Maarten (Dutch part); Suriname; Trinidad and Tobago; Turks and Caicos Islands; United States; Venezuela, Bolivarian Republic of; Virgin Islands, British; Virgin Islands, U.S.
Bermuda; Ecuador; Grenada; Saint Pierre and Miquelon
Present - origin uncertain:
Continuing decline in area of occupancy (AOO): Unknown
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 1340000
Continuing decline in extent of occurrence (EOO): Unknown
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: Unknown
Extreme fluctuations in the number of locations: No
Range Map: Click here to open the map viewer and explore range.

Population [top]

Current Population Trend: Decreasing
Additional data:
Continuing decline of mature individuals: Unknown
Extreme fluctuations: No Population severely fragmented: No
Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No

Habitat and Ecology [top]

Habitat and Ecology: This species can be found on lakes, rivers and estuaries, strictly on the coast in some regions (e.g. California) but inland in others (e.g. Florida). It feeds on small fish fry, shrimps, marine worms and occasionally flying ants and other insects. Prey are usually caught by plunge-diving up to 10 m, preceded by prolonged hovering, and it also occasionally performs surface-dipping and aerial hawking. The breeding season begins between April and mid-June depending on locality, and it breeds in a large variety of habitats, from barren sandy beaches to parking lots and roof tops. Individuals form colonies usually between 5 and 200 pairs strong. It is a highly migratory species, though some populations in the north of South America, and on the Pacific coast of Mexico may be year-round residents (del Hoyo et al. 1996).

Systems: Terrestrial; Marine
Continuing decline in area, extent and/or quality of habitat: Unknown
Generation Length (years): 11.7
Movement patterns: Full Migrant
Congregatory: Congregatory (and dispersive)

Citation: BirdLife International. 2012. Sternula antillarum. The IUCN Red List of Threatened Species 2012: e.T22694673A38881097. . Downloaded on 27 November 2015.
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