VU
Hawaiian Goose Branta sandvicensis



Taxonomy

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - D1

Red List history
Year Category Criteria
2016 Vulnerable D1
2012 Vulnerable D1
2008 Vulnerable D1
2007 Vulnerable
2004 Vulnerable
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Threatened
Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 40,500 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 250-999 medium estimated 2011
Population trend Increasing good estimated -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 1-19 - - -
Decline (10 years/3 generation past and future) 1-19 - - -
Number of subpopulations 4 - - -
Largest subpopulations - - -
Generation length (yrs) 12.3 - - -

Population justification: The total population was estimated to be 1,241 individuals in 2004 (based on counts in 2003), 1,744 individuals in 2006 (A. Marshall, D. Hu and K. Misajon in litt. 2007) and c.2,500 individuals in 2011 (A. Marshall in litt. 2012). However, it is expected that fewer than 1,000 have bred successfully in the wild, and maintenance of the current population relies partly on the regular release of captive bred individuals. Hence the effective number of mature individuals falls within the band 250-999.

Trend justification: The total population was estimated to be 960-1,000 birds in 1999, 1,241 individuals in 2004 (USFWS 2004a), 1,744 in 2006 (A. Marshall, D. Hu and K. Misajon in litt. 2007) and 2,500 in 2011 (A. Marshall in litt. 2012). On Kaua'i, population growth from 2004-2006 can be attributed solely to natural recruitment as no releases of captive-bred birds occurred during that time period. On Maui, the population remains steady, owing in part to captive releases, as well as to predator control. On Big Island, the population has slightly increased, partly owing to natural recruitment at Hakalau National Wildlife Refuge, better recruitment at Hawai'i Volcanoes National Park post-drought, and some captive releases (A. Marshall, D. Hu and K. Misajon in litt. 2007).


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
USA N Extant Yes

Important Bird and Biodiversity Areas (IBA)
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

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Grassland Subtropical/Tropical Dry major resident
Shrubland Subtropical/Tropical Moist major resident
Altitude 1500 - 2500 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
Past, Unlikely to Return Minority (<50%) Negligible declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Livestock farming & ranching - Small-holder grazing, ranching or farming Timing Scope Severity Impact
Past, Unlikely to Return Minority (<50%) Negligible declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Climate change & severe weather Timing Scope Severity Impact
Past, Likely to Return Whole (>90%) Rapid Declines Past Impact
Stresses
Ecosystem degradation, Reduced reproductive success, Species mortality
Human intrusions & disturbance Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Species disturbance, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species - 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 - Named species - Cyathostoma bronchialis 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 - Named species - Felis catus 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 - Named species - Herpestes javanicus_old 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 - Named species - Mycobacterium avium 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 - Named species - 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 - Named species - 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 - Named species - Sus domesticus Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Reduced reproductive success

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Food - human - - Non-trivial Recent
Pets/display animals, horticulture - - International Non-trivial Recent

Recommended citation
BirdLife International (2019) Species factsheet: Branta sandvicensis. Downloaded from http://www.birdlife.org on 21/08/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/08/2019.