Buru Cuckooshrike (Coracina fortis) | Details

Buru Cuckooshrike Coracina fortis

Current view: Data table and detailed info

Taxonomy

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.

IUCN Red List criteria met and history

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2023	Near Threatened	B1b(iii)
2016	Near Threatened	C1;D1
2012	Near Threatened	C1;D1
2008	Near Threatened	C1; D1
2004	Near Threatened
2000	Lower Risk/Near Threatened
1996	Vulnerable
1994	Vulnerable
1988	Near Threatened

Species attributes

Migratory status	not a migrant	Forest dependency	medium
Land-mass type		Average mass	-

Range

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	6,400 km²	medium
Severely fragmented?	no	-

Population

	Estimate	Data quality	Derivation	Year of estimate
Population size	13000-40000 mature individuals	poor	inferred	2022
Population trend	decreasing	-	suspected	2016-2029
Rate of change over the past 10 years/3 generations (longer of the two periods)	1-9,5%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	1-9,5%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	1-9,5%	-	-	-
Generation length	4.2 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: In this species' range, there was c. 3,000 km² of forest (with >50% canopy cover) in 2021 (per Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). There are no direct density estimates available for this species, but other Coracina cuckooshrikes in Wallacea have been recorded at c.15-40 mature individuals/km² (see, e.g., Poulsen et al. [1999]). Adopting the 25th and 75th percentiles, C. fortis is inferred to occur at a density of c. 22-33 mature individuals/km². The species may occur at a relatively low occupancy (see Marsden et al. 1997, eBird 2022), which is set here to 20-40% on the grounds that not all forest will be suitable and/or occupied. These parameters give a total population of c.13,00-40,000 mature individuals, although the data quality of this inferred population size is set to low.

Trend justification: In the three generations (12.6 years; Bird et al. 2020) to 2022, forest cover in this species' range reduced by c. 5-6% (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein), and this is thought to have had broadly equivalent impacts on the species population size. Thus the species is suspected of having declined by 1-9% (with a best estimate of 5%) over the past ten years, and the same rate is precautionarily projected into the future.

Country/territory distribution

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Indonesia	extant	native	yes

Important Bird and Biodiversity Areas (IBA)

Country/Territory	IBA Name
Indonesia	Gunung Kepala Madang

Habitats & altitude

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Altitude	0 - 1500 m	Occasional altitudinal limits

Threats & impact

Threat (level 1)

Threat (level 2)

Impact and Stresses

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]