LC
Masked Booby Sula dactylatra



Taxonomy

Taxonomic note
Sula dactylatra (AOU 1998 + updates) and Sula tasmani (Christidis and Boles 1994) have been lumped as S. dactylatra following Christidis and Boles (2008).

Taxonomic source(s)
Christidis, L. and Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Australia.
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
- - -

Red List history
Year Category Criteria
2018 Least Concern
2016 Least Concern
2012 Least Concern
2010 Least Concern
2008 Not Recognised
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 211,000,000 km2 medium
Extent of Occurrence (non-breeding) 128,000,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size unknown - - -
Population trend decreasing - inferred -
Generation length 16.3 years - - -

Population justification: The global population size has not been quantified, but this species is described as 'fairly common' (Stotz et al. 1996).

Trend justification: The population is suspected to be in decline owing to predation by invasive species and unsustainable levels of exploitation.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
American Samoa extant native yes
Anguilla (to UK) extant native yes
Antigua and Barbuda extant native yes
Aruba (to Netherlands) extant native yes
Australia extant native yes
Bahamas extant native yes
Barbados extant native yes
Belize extant native yes
Bermuda (to UK) extant native yes
Bonaire, Sint Eustatius and Saba (to Netherlands) extant native yes
Brazil extant native yes
Cape Verde extant native yes
Cayman Islands (to UK) extant native yes
Chile extant native yes
Christmas Island (to Australia) extant native yes
Cocos (Keeling) Islands (to Australia) extant native yes
Colombia extant native yes
Comoros extant native yes
Cook Islands extant native yes
Costa Rica extant native yes
Cuba extant native yes
Curaçao (to Netherlands) extant native yes
Dominica extant native yes
Dominican Republic extant native yes
Ecuador extant native yes
Egypt extant native yes
Eritrea extant native yes
Fiji extant native yes
French Polynesia extant native yes
Grenada extant vagrant yes
Guadeloupe (to France) extant native yes
Guam (to USA) extant native yes
Guatemala extant native yes
Haiti extant native yes
Honduras extant uncertain
India extant native yes
Indonesia extant native yes
Iran, Islamic Republic of extant native yes
Jamaica extant native yes
Japan extant native yes
Kenya extant native yes
Kiribati extant native yes
Malaysia extant native yes
Maldives extant vagrant yes
Marshall Islands extant native yes
Martinique (to France) extant native yes
Mauritius extant native yes
Mayotte (to France) extant native yes
Mexico extant native yes
Micronesia, Federated States of extant native yes
Montserrat (to UK) extant native yes
New Caledonia (to France) extant native yes
New Zealand extant native yes
Nicaragua extant native yes
Norfolk Island (to Australia) extant native yes
Northern Mariana Islands (to USA) extant native yes
Oman extant native yes
Pakistan extant native yes
Palau extant native yes
Panama extant native yes
Papua New Guinea extant native yes
Peru extant native yes
Philippines extant native yes
Pitcairn Islands (to UK) extant native yes
Puerto Rico (to USA) extant native yes
Réunion (to France) extant native yes
Samoa extant native yes
São Tomé e Príncipe extant native yes
Seychelles extant native yes
Sint Maarten (to Netherlands) extant native yes
Solomon Islands extant native yes
Somalia extant native yes
Spain extant vagrant yes
Sri Lanka extant native yes
St Helena (to UK) extant native yes
St Kitts and Nevis extant native yes
St Lucia extant native yes
St Martin (to France) extant native
St Vincent and the Grenadines extant native yes
Tanzania extant native yes
Thailand extant native yes
Tonga extant native yes
Trinidad and Tobago extant native yes
Turks and Caicos Islands (to UK) extant native yes
Tuvalu extant native yes
United Arab Emirates extant vagrant yes
United States Minor Outlying Islands (to USA) extant native yes
USA extant native yes
Venezuela extant native yes
Vietnam extant native
Virgin Islands (to UK) extant native yes
Virgin Islands (to USA) extant native yes
Wallis and Futuna Islands (to France) extant native yes
Yemen extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Anguilla (to UK) Dog Island
Antigua and Barbuda Redonda
Australia Raine Island, Moulter and Maclennan Cays
Bahamas Booby Rocks and Pirates Bay
Brazil Atol das Rocas
French Polynesia Clipperton
French Polynesia Clipperton Marine
French Southern Territories Tromelin
Indonesia Pulau Manuk
Jamaica Pedro Cays and Bank
Kiribati Enderbury Island
Kiribati Malden Island
Kiribati Malden Island Marine
Kiribati McKean Island
Kiribati McKean Island Marine
Kiribati Phoenix Islands Marine
Oman Halaaniyaat Islands
Puerto Rico (to USA) Mona and Monito
Seychelles Boudeuse Island
Seychelles Cosmoledo
St Helena (to UK) Boatswainbird Island
St Helena (to UK) Letterbox Peninsula
Tanzania Latham Island
Trinidad and Tobago St Giles Islands
United States Minor Outlying Islands (to USA) Baker Island
United States Minor Outlying Islands (to USA) Howland and Baker Marine
United States Minor Outlying Islands (to USA) Howland Island
United States Minor Outlying Islands (to USA) Jarvis Island
United States Minor Outlying Islands (to USA) Jarvis Island Marine
USA Northwestern Hawaiian Islands
Venezuela Isla La Blanquilla
Venezuela Isla La Blanquilla - Marine
Virgin Islands (to UK) Anegada: Western salt ponds and coastal areas
Virgin Islands (to USA) North-west Cays
Yemen Darsa
Yemen Kal Farun (Socotra)
Yemen Sabuniya (Socotra)
Yemen Samha

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Intertidal Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc major resident
Marine Intertidal Shingle and/or Pebble Shoreline and/or Beaches major resident
Marine Neritic Macroalgal/Kelp major resident
Marine Neritic Pelagic major resident
Marine Neritic Seagrass (Submerged) major resident
Marine Neritic Subtidal Loose Rock/pebble/gravel major resident
Marine Neritic Subtidal Rock and Rocky Reefs major resident
Marine Neritic Subtidal Sandy major resident
Marine Neritic Subtidal Sandy-Mud major resident
Marine Oceanic Epipelagic (0-200m) major resident
Marine Oceanic Mesopelagic (200-1000m) major resident
Altitude   Occasional altitudinal limits  

Threats & impact
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
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Species disturbance, Reduced reproductive success, Species mortality
Human intrusions & disturbance Recreational activities 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 - Rattus rattus Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Reduced reproductive success

Recommended citation
BirdLife International (2024) Species factsheet: Masked Booby Sula dactylatra. Downloaded from https://datazone.birdlife.org/species/factsheet/masked-booby-sula-dactylatra on 09/12/2024.
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 09/12/2024.