• 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. 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
-	-	-

Red List history

Year	Category	Criteria
2021	Near Threatened	B2ab(ii,iii,iv,v); C2a(i)
2016	Vulnerable	D1
2012	Vulnerable	D1
2008	Vulnerable	D1
2007	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	50,700 km2	medium
Area of Occupancy (breeding/resident)	2,564 km2
Number of locations	4-10	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	1700-2200 mature individuals	good	estimated	2018
Population trend	increasing	good	estimated	-
Generation length	11.54 years	-	-	-
Number of subpopulations	3	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: Recent population estimates have included 1,754 in 2006, 2,019 in 2007, 1,900 - 1,950 in 2008, 1,877 - 1,927 in 2009, 1,888 - 1,978 in 2010 (USFWS 2011), 2,465-2,555 in 2011 (VanderWerf 2012), 3,039 in 2015 (Amidon 2017), and 2,855 in 2016 (USFWS 2018). In 2018, the population was estimated at 3,252 individuals, including 1,104 on Hawai‘i (including 598 birds relocated from Kaua‘i), 627 on Maui, 37 on Moloka’i, 1,482 on Kaua‘i and 2 on O‘ahu (USFWS 2018).

For some time, all populations were dependent on continued releases of captive birds to persist (USFWS 2004), but releases ceased by the late 2000s (USFWS 2011). The populations on Kaua‘i, Hawai‘i Island and Maui are now considered to be self-sustaining (USFWS 2018). The population on Moloka’i is not yet successfully breeding (USFWS 2019), and so it is excluded from this assessment. In 2011-2016, 640 individuals were removed from a site on Kaua‘i to reduce the risk of bird strike at an airport, and moved to Hawai‘i and Maui (VanderWerf 2012, USFWS 2018).

The total population size of all established subpopulations is here placed in the band 2,600 - 3,300 individuals, roughly equivalent to 1,700 - 2,200 mature individuals.

Although the species is capable of flying between islands (Banko and Elder 1990), it is assumed that subpopulations on separate islands are largely isolated.

Trend justification: Historically, the population declined rapidly, and in 1951, the wild population was estimated at 30 individuals (Smith 1952). Captive breeding and reintroduction efforts began in the 1960s, resulting in an increasing population, although the population size declined sharply in 1981-1982 when releases temporarily ceased, indicating that wild populations were only sustained through continued releases (Black et al. 1991). In 1989 the population size was estimated at 476-555 individuals (Black et al. 1991). This grew to around 600 individuals in 1995 (Black 1995), c.885 in 1998, and c.1,249 individuals in 2004 (USFWS 2004). More recent population estimates have included 1,754 in 2006, 2,019 in 2007, 1,900 - 1,950 in 2008, 1,877 - 1,927 in 2009, 1,888 - 1,978 in 2010 (USFWS 2011), 2,465-2,555 in 2011 (VanderWerf 2012), 3,039 in 2015 (Amidon 2017), 2,855 in 2016 (USFWS 2018) and 3,252 in 2018 (USFWS 2019).

Counts since 2004 have included individuals on Moloka’i, which is not yet considered to be an established population. Nevertheless, the global population size is increasing. The population has grown rapidly on Kaua‘i, where there are no mongooses and there may be more available habitat than on other range islands (USFWS 2018). Populations on Maui and Hawai‘i have remained stable or increased slightly in recent years (VanderWerf 2012, USFWS 2018). A recent analysis of subpopulation trends found that populations at Hawai‘i Volcanoes National Park (Hawai‘i), Maui, Haleakala National Park (Maui), and Kaua‘i were all either increasing or stable (Amidon 2017).

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

Country/Territory	IBA Name
USA	Haleakala
USA	Hamakua Forests
USA	Hanalei National Wildlife Refuge
USA	Kauai Forests and Uplands
USA	Kilauea Point National Wildlife Refuge
USA	Kona Forests
USA	Mauna Loa-Kilauea Forests

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Pastureland	suitable	resident
Grassland	Subtropical/Tropical Dry	major	resident
Grassland	Subtropical/Tropical High Altitude	suitable	resident
Introduced vegetation		suitable	resident
Shrubland	Subtropical/Tropical High Altitude	major	resident
Shrubland	Subtropical/Tropical Moist	suitable	resident
Altitude	0 - 2700 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
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Small-holder grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Whole (>90%)		Rapid Declines		Past Impact
		Stresses Species disturbance, Species mortality
Climate change & severe weather	Droughts	Timing		Scope		Severity		Impact
		Past, Likely to Return		Whole (>90%)		Causing/Could cause fluctuations		Past Impact
		Stresses Ecosystem degradation, Reduced reproductive success, Species mortality
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Climate change & severe weather	Storms & flooding	Timing		Scope		Severity		Impact
		Past, Likely to Return		Whole (>90%)		Causing/Could cause fluctuations		Past Impact
		Stresses Species disturbance, Reduced reproductive success, Species mortality
Energy production & mining	Renewable energy	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion, Species mortality
Geological events	Volcanoes	Timing		Scope		Severity		Impact
		Past, Likely to Return		Minority (<50%)		Rapid Declines		Past Impact
		Stresses Ecosystem degradation, Ecosystem conversion, Reduced reproductive success, Species mortality
Human intrusions & disturbance	Recreational activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Bos taurus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Canis familiaris	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Capra hircus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Species mortality, Other
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Herpestes auropunctatus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Ovis aries	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus exulans	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus norvegicus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus rattus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Sus domesticus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Species disturbance, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Toxoplasma gondii	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Unspecified species	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation, Reduced reproductive success, 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
Food - human	subsistence, national
Pets/display animals, horticulture	international

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Recommended citation
BirdLife International (2024) Species factsheet: Hawaiian Goose Branta sandvicensis. Downloaded from https://datazone.birdlife.org/species/factsheet/hawaiian-goose-branta-sandvicensis on 22/12/2024.
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 22/12/2024.