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Xantus's Murrelet Synthliboramphus hypoleucus

IUCN Red List Criteria

Critically Endangered  
Endangered  
Vulnerable B1ab(iv,v)+2ab(iv,v) 

IUCN Red List history

Year Category
2012 Vulnerable
2010 Vulnerable
2008 Vulnerable
2007 Vulnerable
2005 Vulnerable
2004 Vulnerable
2000 Vulnerable
1994 Lower Risk/Near Threatened
1988 Near Threatened

Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type shelf island
Average mass 167 g

Distribution

  Estimate Data quality
Extent of Occurrence breeding/resident (km2) 300 medium
Extent of Occurrence non-breeding (km2) 770,000 medium
Area of Occupancy breeding/resident (km2) 300 medium
Number of locations 9 -
Fragmentation -

Population & trend

  Estimate Data quality Derivation Year of estimate
No. of mature individuals 6000-15000 medium Estimated 2003
Population trend Decreasing poor -
Number of subpopulations 1 - - -
Largest subpopulation - - -
Generation length (yrs) 12.1 - - -
Population justification: Based on at sea survey data from 1975 to 2003, Karnovsky et al. (2005) were able to estimate a current North American at-sea population of 39,700, of which 17,000 are likely to be mature breeding individuals. Although this estimate is based on extrapolation from survey data, the population estimate is perhaps best placed conservatively at 10,000-19,999 individuals. This equates to 6,667-13,333 mature individuals, rounded here to 6,000-15,000 mature individuals.
Trend justification: A number of colonies have been extirpated by introduced predators and alien invasive species continue to threaten some colonies. A number of other threatening processes are on-going, the combined effects of which are suspected to be causing a moderate decline in this species's global population.

Country/Territory distribution

Country/Territory Occurrence status Presence Breeding Non-breeding Passage
Canada Native Extant   Yes  
Mexico Native Extant Yes    
USA Native Extant Yes    

Important Bird Areas where this species has triggered the IBA criteria

Country/Territory IBA Name IBA link
USA Channel Islands - Northern site factsheet

Habitats & altitude

Habitat (level 1) Habitat (level 2) Importance Occurrence
Marine Coastal/Supratidal Sea Cliffs and Rocky Offshore Islands major breeding
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) suitable resident
Marine Oceanic Mesopelagic (200-1000m) suitable resident
Altitude 0 - 100 m Occasional altitudinal limits  

Threats & impact

Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Fishing & harvesting aquatic resources / Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Decline Medium Impact:
Stresses
Indirect ecosystem effects, Species disturbance, Species mortality
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Slow, Significant Decline Low Impact: 5
Stresses
Indirect ecosystem effects, Ecosystem degradation, Reduced reproductive success, Species mortality
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Decline Medium Impact:
Stresses
Species disturbance, Ecosystem degradation, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases / Black Rat (Rattus rattus) Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Decline Medium Impact:
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases / Domestic Cat (Felis catus) Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Decline Medium Impact:
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Problematic native species/diseases Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Decline Low Impact: 5
Stresses
Reduced reproductive success
Natural system modifications Other ecosystem modifications Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation, Reduced reproductive success
Pollution Industrial & military effluents / Oil spills Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact:
Stresses
Species mortality
Pollution Industrial & military effluents / Type Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Unknown Unknown Unknown
Stresses
Ecosystem degradation

Recommended citation
BirdLife International (2014) Species factsheet: Synthliboramphus hypoleucus. Downloaded from http://www.birdlife.org on 14/07/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 14/07/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Key facts
Current IUCN Red List category Vulnerable
Family Alcidae (Auks)
Species name author X
Population size 6000-15000 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 300 km2
Country endemic? No
Links to further information
- Summary information on this species