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

Taxonomic source(s)
Brooke, M. de L. 2004. Albatrosses and Petrels Across the World. Oxford University Press, Oxford.
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
-	A3bce+4bce	A3bce+4bce; B2ab(v); C1

Red List history

Year	Category	Criteria
2018	Endangered	A3bce+4bce
2016	Vulnerable	B2ab(iv,v)
2012	Vulnerable	B2ab(iv,v)
2010	Vulnerable	B2a+b(iv,v)
2008	Vulnerable	B2a+b(iv,v)
2007	Vulnerable
2006	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Lower Risk/Least Concern

Migratory status	full migrant	Forest dependency	medium
Land-mass type		Average mass	434 g

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	22,000,000 km2	medium
Area of Occupancy (breeding/resident)	370 km2	medium
Number of locations	6-10	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	7500-16600 mature individuals	medium	estimated	1995
Population trend	decreasing	medium	estimated	1951-2010
Rate of change over the future 10 years/3 generations (longer of the two periods)	50-79%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	50-79%	-	-	-
Generation length	19.8 years	-	-	-
Number of subpopulations	5	-	-	-

Population justification: Spear et al. (1995) give a best estimate of 3,750-4,500 breeding pairs based on at-sea surveys. This roughly equates to 7,500-9,000 mature individuals, and 11,250-13,500 individuals in total. The discovery of possibly several thousand birds breeding on Lana'i during terrestrial surveys in 2006-2007 and two small colonies on West Maui (J. Penniman in litt. 2007), probably in the tens or low hundreds of birds (D. Ainley in litt. 2007), may bring the estimated breeding population close to the upper estimate of 6,500-8,300 pairs calculated by Spear et al. (1995). However, the rapid decline in at least the population on Kaua'i would suggest that the population size may now in fact be smaller than this. Given uncertainty regarding overall trends, the upper and lower bounds from Spear et al. (1995) are used here, i.e. 3,750-8,300 pairs, or 7,500-16,600 mature individuals.

Trend justification: A standard population monitoring technique has not yet been fully developed for use across colonies and survey sites. However, efforts are underway among collaborating scientists to standardize metrics and procedures, so that population trends can be monitored more effectively on each of the islands. Pterodroma sandwichensis is suspected to have declined severely for the past few centuries, owing primarily to predation by introduced species at nesting colonies and urbanization (D. Ainley in litt. 2007), as well as collisions with utility structures and power lines. On Kaua'i, the population has declined by as much as 78% between 1993 and 2013 (Raine et al. 2017), but the rate of subpopulation decline probably varies considerably, and as such the overall trend is difficult to quantify. Assuming that, apart from the population on Kaua'i, all other subpopulations are overall stable, the ongoing global rate of decline would be c.19-42.5% over three generations (59.4 years), depending on the proportion of the overall population previously found on Kaua'i. Terrestrial and at-sea threats are likely to impact all subpopulations though, so they are all likely in decline (A. Raine in litt. 2018). If all subpopulations were declining at the same rate as on Kaua'i, the reduction over three generations could even reach as high as 99%. In the absence of evidence from other subpopulations, the overall ongoing rate of decline is tentatively placed here in the range 50-79% over three generations, and is suspected to continue into the future.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
French Polynesia	extant	uncertain
Indonesia	extant	vagrant
Japan	extant	vagrant
Kiribati	extant	uncertain
Philippines	extant	vagrant
United States Minor Outlying Islands (to USA)	extant	uncertain
USA	extant	native		yes

Country/Territory	IBA Name
USA	Haleakala
USA	Kauai Forests and Uplands
USA	Lana`ihale
USA	Molokai Forests

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	breeding
Grassland	Subtropical/Tropical High Altitude	suitable	breeding
Marine Neritic	Pelagic	major	non-breeding
Marine Neritic	Pelagic	major	breeding
Marine Oceanic	Epipelagic (0-200m)	major	non-breeding
Marine Oceanic	Epipelagic (0-200m)	major	breeding
Shrubland	Subtropical/Tropical High Altitude	suitable	breeding
Altitude	850 - 3000 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Livestock farming & ranching - Scale Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion, Species mortality
Biological resource use	Fishing & harvesting aquatic resources - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Species mortality
Climate change & severe weather	Temperature extremes	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Causing/Could cause fluctuations		Medium Impact: 6
		Stresses Indirect ecosystem effects, Reduced reproductive success, Species mortality
Energy production & mining	Renewable energy	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Axis axis	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Bos taurus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Canis familiaris	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Capra hircus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Herpestes auropunctatus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Ovis aries	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Psidium cattleianum	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant 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%)		Slow, Significant Declines		Medium Impact: 6
		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%)		Slow, Significant Declines		Medium Impact: 6
		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%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Sus domesticus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Tyto alba	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Reduced reproductive success, Species mortality
Pollution	Excess energy - Light pollution	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses 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
Transportation & service corridors	Utility & service lines	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Hawaiian Petrel Pterodroma sandwichensis. Downloaded from https://datazone.birdlife.org/species/factsheet/hawaiian-petrel-pterodroma-sandwichensis on 25/11/2024.
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 25/11/2024.