Sternula antillarum


Taxonomy [top]

Kingdom Phylum Class Order Family

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 Notes: The BirdLife Taxonomic Working Group is aware that phylogenetic analyses have been published which have proposed generic rearrangements which may affect this species, but prefers to wait until work by other taxonomists reveals how these changes affect the entire groups involved.

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.

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).

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:
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population Trend: Decreasing

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

Citation: BirdLife International 2012. Sternula antillarum. The IUCN Red List of Threatened Species. Version 2015.2. <>. Downloaded on 03 September 2015.
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