• 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.
Turbott, E.G. 1990. Checklist of the Birds of New Zealand. Ornithological Society of New Zealand, Wellington.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2022	Least Concern
2016	Near Threatened	C2a(ii)
2012	Near Threatened	C2a(ii)
2008	Near Threatened	C2a(ii)
2006	Near Threatened
2004	Near Threatened
2000	Lower Risk/Least Concern
1994	Lower Risk/Least Concern
1988	Lower Risk/Least Concern

Migratory status	not a migrant	Forest dependency	does not normally occur in forest
Land-mass type	Australia	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	5,000,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	11000-19000, 15000 mature individuals	poor	suspected	2020
Population trend	stable	medium	inferred	-
Generation length	5.7 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: Over a decade ago, there were thought to be 10,000 Blue-billed Ducks in south-eastern Australia and 5,000 in south-western Australia (Wetlands International 2019). No more robust estimation has been made since, however the population is plausibly much larger. Of 9,000 counted in Victoria in 2019, over 5,400 were at the Western Treatment Plant alone (Menkhorst et al. 2019), with up to 12,000 being counted there in dry years (Loyn et al. 2014a,b). The plausible population size is therefore suspected to number between 11,000 and 19,000, with a best estimate of c.15,000 mature individuals (Menkhorst et al. 2021).

Trend justification: Although numbers vary between years (Menkhorst et al. 2018, 2019), there is no suggestion of a decline in long term counts (Clemens et al. 2019, Menkohorst et al. 2021) and therefore the population is inferred to be stable.

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

Country/Territory	IBA Name
Australia	Arcoona Lakes
Australia	Benger Swamp
Australia	Carrum Wetlands
Australia	Coongie Lakes
Australia	Devilbend Reservoir
Australia	Kangaroo Island
Australia	Lake Bathurst
Australia	Lake Bindegolly
Australia	Lake Corangamite Complex
Australia	Lake McLarty
Australia	North Victorian Wetlands
Australia	Paroo Floodplain and Currawinya
Australia	Peel-Harvey Estuary
Australia	Swan Bay and Port Phillip Bay Islands
Australia	Towerrining Lake and Moodiarrup Swamps
Australia	Watervalley Wetlands
Australia	Werribee and Avalon

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Wetlands (inland)	Bogs, Marshes, Swamps, Fens, Peatlands	major	resident
Wetlands (inland)	Permanent Freshwater Lakes (over 8ha)	major	resident
Wetlands (inland)	Permanent Rivers/Streams/Creeks (includes waterfalls)	suitable	non-breeding
Altitude	0 - 500 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Species disturbance, Species mortality
Climate change & severe weather	Droughts	Timing		Scope		Severity		Impact
		Future		Minority (<50%)		No decline		No/Negligible Impact: 2
		Stresses Ecosystem degradation
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		No decline		Low Impact: 4
		Stresses Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Bos taurus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Cyprinus carpio	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Competition
Natural system modifications	Dams & water management/use - Abstraction of surface water (agricultural use)	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		No decline		Low Impact: 5
		Stresses Ecosystem degradation
Residential & commercial development	Tourism & recreation areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Species disturbance

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Recommended citation
BirdLife International (2024) Species factsheet: Blue-billed Duck Oxyura australis. Downloaded from https://datazone.birdlife.org/species/factsheet/blue-billed-duck-oxyura-australis 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.