• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

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. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2018	Least Concern
2016	Least Concern
2012	Least Concern
2009	Least Concern
2008	Least Concern
2004	Least Concern
2000	Lower Risk/Least Concern
1994	Lower Risk/Least Concern
1988	Lower Risk/Least Concern

Migratory status	full migrant	Forest dependency	does not normally occur in forest
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	10,600,000 km2	medium
Extent of Occurrence (non-breeding)	17,400,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	poor	estimated	2009
Population trend	decreasing	-	suspected	-
Generation length	11 years	-	-	-

Population justification: The population is estimated at 250,000-1,000,000 individuals.

Trend justification: The population is suspected to be in decline owing to disturbance of its nesting sites (del Hoyo et al. 1996).

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Argentina	extant	native		yes
Brazil	extant	native		yes
Chile	extant	native		yes
Ecuador	extant	native			yes
Peru	extant	native		yes
Uruguay	extant	native	yes

Country/Territory	IBA Name
Argentina	Península Valdés, Punta León y Punta Loma
Argentina	Playa Punta Mogotes y Puerto de Mar del Plata
Chile	Desembocadura del Río Imperial
Chile	Estero Compu

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Marine Coastal/Supratidal	Sea Cliffs and Rocky Offshore Islands	major	breeding
Marine Intertidal	Rocky Shoreline	major	breeding
Marine Intertidal	Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc	major	breeding
Marine Intertidal	Tidepools	major	breeding
Marine Neritic	Macroalgal/Kelp	major	non-breeding
Marine Neritic	Macroalgal/Kelp	major	breeding
Marine Neritic	Pelagic	suitable	non-breeding
Marine Neritic	Pelagic	suitable	breeding
Marine Neritic	Seagrass (Submerged)	major	non-breeding
Marine Neritic	Seagrass (Submerged)	major	breeding
Marine Neritic	Subtidal Loose Rock/pebble/gravel	major	non-breeding
Marine Neritic	Subtidal Loose Rock/pebble/gravel	major	breeding
Marine Neritic	Subtidal Rock and Rocky Reefs	major	non-breeding
Marine Neritic	Subtidal Rock and Rocky Reefs	major	breeding
Marine Neritic	Subtidal Sandy	major	non-breeding
Marine Neritic	Subtidal Sandy	major	breeding
Marine Neritic	Subtidal Sandy-Mud	major	non-breeding
Marine Neritic	Subtidal Sandy-Mud	major	breeding
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Human intrusions & disturbance	Recreational activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species disturbance, Reduced reproductive success

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Recommended citation
BirdLife International (2024) Species factsheet: South American Tern Sterna hirundinacea. Downloaded from https://datazone.birdlife.org/species/factsheet/south-american-tern-sterna-hirundinacea on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.