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

Taxonomic note

Acrocephalus luscinius, A. hiwae, A. yamashinae, A. astrolabii and A. nijoi (del Hoyo and Collar 2016) were previously lumped as A. luscinius following Sibley & Monroe (1990, 1993).

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2023	Extinct
2016	Extinct
2012	Not Recognised
2008	Not Recognised
2004	Not Recognised
2000	Not Recognised
1994	Not Recognised
1988	Not Recognised

Migratory status	not a migrant	Forest dependency	low
Land-mass type		Average mass	28 g

	Estimate	Data quality
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	-	-	-
Population trend		medium	-	2009-2026
Generation length	2.59 years	-	-	-

Population justification: A tiny population was reported to remain on the uninhabited island, but has not been observed since the mid-1990s despite extensive surveys in 2000, 2001, 2008, and 2009 (USFWS 1998, Esselstyn et al. 2003, Camp et al. 2009, Amidon et al. 2014), and the species is now considered to be Extinct.

Trend justification:

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Northern Mariana Islands (to USA)	extinct	native	yes

Country/Territory	IBA Name
Northern Mariana Islands (to USA)	Aguiguan Island and Naftan Rock

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	suitable	resident
Shrubland	Subtropical/Tropical Moist	suitable	resident
Altitude	0 - 500 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Whole (>90%)		Rapid Declines		Past Impact
		Stresses Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Capra hircus	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Slow, Significant Declines		Past Impact
		Stresses Ecosystem degradation

Purpose	Scale
Pets/display animals, horticulture	international

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Recommended citation
BirdLife International (2024) Species factsheet: Aguijan Reed-warbler Acrocephalus nijoi. Downloaded from https://datazone.birdlife.org/species/factsheet/aguijan-reed-warbler-acrocephalus-nijoi on 26/12/2024.
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 26/12/2024.