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

Taxonomic source(s)
Christidis, L. and Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Australia.
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.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	A2bc+3bc+4bc

Red List history

Year	Category	Criteria
2022	Vulnerable	A2bc+3bc+4bc
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	altitudinal migrant	Forest dependency	medium
Land-mass type		Average mass	256 g

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	401,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	17600-35200, 25300 mature individuals	poor	estimated	2020
Population trend	decreasing	-	inferred	2007-2034
Rate of change over the past 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Generation length	8.9 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The estimate used here is the product of three predicted AOO measures (spanning 22,700-40,000 km²) from Cameron et al. (2021), the smallest being the number of 2x2 km squares for which there are records since 1990, the latter being an arbitrary value of nearly double this to account for incomplete survey effort of potentially suitable habitat. The density applied assumes an average density of 3.1 birds/km², that the 2019–2020 fire season reduced the carrying capacity of 40% of grid cells by half and resulted in 10% mortality (Cameron et al. 2021). Combining these measures and uncertainty creates a likely population estimate of between 17,600 and 35,200 mature individuals, with a most likely figure (the midpoint) of 25,300.

Trend justification:

It is estimated that the 2019–2020 fire season reduced the carrying capacity of 40% of grid cells by half and resulted in 10% mortality (Cameron et al. 2021). Apart from fire impacts, trend data are not entirely consistent. Reporting rates from 500-m radius area searches (20,094 individuals; 328,201 surveys), arguably the most reliable of the available survey methods for the species, declined by 69% from 1999–2019. This follows a significant decline of 22% between 1977–1981 and 1998–2001 (Barrett et al. 2002), including a decline of 44% in New South Wales (Barrett et al. 2007). 

However, the decline in 2-ha 20-min surveys from 1999–2019 (8,987 individuals; 267,885 surveys) was only 15% (BirdLife Australia 2020). In the Australian Capital Territory, reporting rates were three times higher in 1987–1989 than the fairly stable reporting rate since (Canberra Ornithologists Group 2020). Combining these analyses and incorporating temporal and spatial uncertainties, Cameron et al. (2021) best estimated a global rate of decline of 30-49% over the past three generations (27 years; Bird et al. 2020).

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Plantations	suitable	non-breeding
Artificial/Terrestrial	Urban Areas	suitable	non-breeding
Forest	Subtropical/Tropical Moist Lowland	suitable	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Altitude	0 - 2000 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Biological resource use	Logging & wood harvesting - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion, Reduced reproductive success
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Slow, Significant Declines		Medium Impact: 7
		Stresses Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather	Temperature extremes	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Problematic native species/diseases - Unspecified species	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Competition
Natural system modifications	Fire & fire suppression - Increase in fire frequency/intensity	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Species mortality
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion

Purpose	Scale
Pets/display animals, horticulture	subsistence, national, international

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Recommended citation
BirdLife International (2024) Species factsheet: Gang-gang Cockatoo Callocephalon fimbriatum. Downloaded from https://datazone.birdlife.org/species/factsheet/gang-gang-cockatoo-callocephalon-fimbriatum on 18/12/2024.
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 18/12/2024.