• 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
2024	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)	1,550,000 km2	medium
Extent of Occurrence (non-breeding)	30,000,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	70000 mature individuals	poor	estimated	2009
Population trend	decreasing	-	suspected	-
Generation length	6.12 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: It has a relatively small estimated population size (70,000 mature individuals; Partners in Flight 2023), but this does not approach Criteria C or D thresholds.

Trend justification: Considering its population trend over three generations (c. 18 years), data from the Christmas Bird Count (Meehan et al. 2022) indicate a decline of c. 23% (albeit with wide confidence intervals), although the underlying interannual trend data suggest the population has fluctuated over the last decade, following a long-term decline. Over the same period, Partners in Flight (2023) reports a decline of c. 11% (albeit with large confidence intervals), and eBird also indicates a decline (Fink et al. 2023). Although the population has declined and may still be declining, it does not currently appear to be declining at a rate approaching Criterion A thresholds.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Argentina	extant	native
Canada	extant	native		yes	yes	yes
Chile	extant	native
Colombia	extant	native			yes
Costa Rica	extant	native			yes
Ecuador	extant	native			yes
El Salvador	extant	native
Falkland Islands (Malvinas)	extant	vagrant
Guatemala	extant	native			yes
Honduras	extant	native			yes
Mexico	extant	native
Panama	extant	native			yes
Peru	extant	native			yes
USA	extant	native		yes	yes	yes

Country/Territory	IBA Name
Canada	Barkley Sound
Canada	White Islets and Wilson Creek
Costa Rica	Nicoya Gulf mangroves and coastal areas
USA	Homer Spit
USA	Mendenhall Wetlands
USA	Northern Montague Island

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Grassland	Tundra	suitable	breeding
Marine Intertidal	Rocky Shoreline	major	non-breeding
Marine Intertidal	Tidepools	major	non-breeding
Rocky areas (eg. inland cliffs, mountain peaks)		major	breeding
Altitude	0 - 1800 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Pollution	Industrial & military effluents - Oil spills	Timing		Scope		Severity		Impact
		Past, Likely to Return		Minority (<50%)		Unknown		Past Impact
		Stresses Species disturbance, Ecosystem degradation, Species mortality
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Species disturbance, Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Surfbird Calidris virgata. Downloaded from https://datazone.birdlife.org/species/factsheet/surfbird-calidris-virgata 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.