• 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.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	D2

Red List history

Year	Category	Criteria
2018	Vulnerable	D2
2016	Vulnerable	D2
2012	Vulnerable	D2
2010	Vulnerable	D2
2008	Vulnerable	D2
2006	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
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)	1,900,000 km2	medium
Area of Occupancy (breeding/resident)	9 km2	medium
Number of locations	3	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	5554 mature individuals	poor	estimated	2004
Population trend	stable	poor	suspected	1965-2010
Generation length	15.6 years	-	-	-
Number of subpopulations	3	-	-	-

Population justification: The world population may be no greater than 10,000 individuals. The estimate of global breeding population, based on on-the-ground counts of nests, is 2,777 breeding pairs (or 5,554 breeding individuals) (Hodum 2012).

Trend justification: The population is thought to be stable although the very small breeding range of the species renders it susceptible to stochastic events.

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

Country/Territory	IBA Name
Chile	Islas Desventuradas
Chile	Parque Nacional Archipiélago de Juan Fernández: Islas Robinson Crusoe and Santa Clara

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Marine Coastal/Supratidal	Sea Cliffs and Rocky Offshore Islands	major	breeding
Marine Intertidal	Rocky Shoreline	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
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Capra hircus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Rapid Declines		Medium Impact: 6
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Named species	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Nasua nasua	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Rapid Declines		Medium Impact: 6
		Stresses Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Masatierra Petrel Pterodroma defilippiana. Downloaded from https://datazone.birdlife.org/species/factsheet/masatierra-petrel-pterodroma-defilippiana on 22/11/2024.
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 22/11/2024.