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

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: http://www.aerc.eu/DOCS/Bird_taxa_of_the_WP15.xls.
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
-	D	D1+2

Red List history

Year	Category	Criteria
2018	Endangered	D
2016	Endangered	D
2012	Endangered	D
2010	Endangered	D1
2008	Endangered	D1
2006	Endangered
2004	Endangered
2000	Endangered
1996	Endangered
1994	Endangered
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	17,500,000 km2	medium
Area of Occupancy (breeding/resident)	1 km2	medium
Number of locations	1	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	196 mature individuals	good	estimated	2011
Population trend	increasing	good	observed	1965-2010
Rate of change over the past 10 years/3 generations (longer of the two periods)	80-100%	-	-	-
Generation length	15.6 years	-	-	-

Population justification: In 2005, the population was thought to include 71 breeding pairs (J. Madeiros in litt. 2005). By 2011, the population reached 98 nesting pairs (Madeiros 2011).

Trend justification: The population has increased from 18 pairs in 1951 to 71 pairs in 2005. This is equivalent to an increase of well over 79% in three generations, given the species's long lifespan. Records of 40 chicks fledged in 2008 and 35 chicks hatched in 2009 suggested the population continues to increase, and indeed by 2011, the population reached 98 nesting pairs (Madeiros 2011).

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Bahamas	extant	vagrant
Bermuda (to UK)	extant	native		yes
Canada	extant	uncertain
Portugal	extant	vagrant
USA	extant	native			yes

Country/Territory	IBA Name
Bermuda (to UK)	Cooper's Island and Castle Islands
USA	Outer Continental Shelf

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Marine Coastal/Supratidal	Sea Cliffs and Rocky Offshore Islands	major	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
Altitude	0 - 79 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
		Past, Unlikely to Return		Whole (>90%)		Rapid Declines		Past Impact
		Stresses Species disturbance, Reduced reproductive success, Species mortality
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather	Storms & flooding	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Causing/Could cause fluctuations		Low Impact: 5
		Stresses Ecosystem degradation, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Apis mellifera	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 - Bubo scandiacus	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Canis familiaris	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Ecosystem degradation, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus norvegicus	Timing		Scope		Severity		Impact
		Past, Likely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus rattus	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 - Sus domesticus	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Majority (50-90%)		Rapid Declines		Past Impact
		Stresses Ecosystem degradation, Reduced reproductive success, Species mortality
Pollution	Excess energy - Light pollution	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Minority (<50%)		Unknown		Past Impact
		Stresses None

Purpose	Scale
Food - human	subsistence, national

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Recommended citation
BirdLife International (2024) Species factsheet: Bermuda Petrel Pterodroma cahow. Downloaded from https://datazone.birdlife.org/species/factsheet/bermuda-petrel-pterodroma-cahow 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.