• 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., 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
-	-	C2a(ii)

Red List history

Year	Category	Criteria
2018	Vulnerable	C2a(ii)
2016	Vulnerable	D1
2012	Vulnerable	D1
2008	Vulnerable	D1
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Lower Risk/Least Concern

Migratory status	not a migrant	Forest dependency	high
Land-mass type		Average mass	50 g

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	640 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	2500-9999 mature individuals	poor	estimated	2018
Population trend	decreasing	poor	inferred	1998-2008
Generation length	3.7 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The population size had been previously thought to be very small. However, population density estimates (e.g. per Walther and Jones 2018) suggest that previous estimates may have been an underestimate. Based on such density estimates the population size is tentatively placed in the range 2,500-9,999 mature individuals.

Trend justification: The population is tentatively considered to be in decline as a result of ongoing habitat degradation.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
São Tomé e Príncipe	extant	native	yes

Country/Territory	IBA Name
São Tomé e Príncipe	Parque Natural Obô de São Tomé e Zona Tampão
São Tomé e Príncipe	São Tomé lowland forests
São Tomé e Príncipe	São Tomé montane and cloud-forests
São Tomé e Príncipe	São Tomé northern savannas

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Plantations	marginal	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Savanna	Dry	marginal	resident
Altitude	0 - 1600 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Scale Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		No decline		Past Impact
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Future		Minority (<50%)		No decline		No/Negligible Impact: 2
		Stresses Ecosystem degradation, Ecosystem conversion
Transportation & service corridors	Roads & railroads	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Ecosystem degradation

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Recommended citation
BirdLife International (2024) Species factsheet: Sao Tome Oriole Oriolus crassirostris. Downloaded from https://datazone.birdlife.org/species/factsheet/sao-tome-oriole-oriolus-crassirostris on 23/12/2024.
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 23/12/2024.