VU
Calayan Rail Gallirallus calayanensis



Taxonomy

Taxonomic source(s)
Allen, D.; Oliveros, C.; Española, C.; Broad, G.; Gonzalez, J.C. T. 2004. A new species of Gallirallus from Calayan island, Philippines. Forktail 20: 1-7.
Allen, D.; Oliveros, C.; Española, C.; Broad, G.; Gonzalez, J.C. T. 2004. A new species of Gallirallus from Calayan island, Philippines. Forktail 20: 1-7.
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. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - D2

Red List history
Year Category Criteria
2016 Vulnerable D2
2015 Vulnerable D2
2012 Vulnerable D2
2011 Vulnerable D1; D2
2008 Vulnerable D1; D2
2005 Vulnerable
2004 Not Recognised
2000 Not Recognised
1994 Not Recognised
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency High
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 70 good
Extent of Occurrence breeding/resident (km2) 90 good
Number of locations 1 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 2500-4300 good estimated 2012
Population trend Stable medium suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations - - -
Largest subpopulations - - -
Generation length (yrs) 3.4 - - -

Population justification: Allen et al. (2004), estimated 100-200 pairs. It has since been found to be locally common, with an estimated area of occupancy of 36 km2. However recent species distribution modelling estimated its area of occupancy at 90.2 km2 (C. Layusa and C. Oliveros in litt. 2012). These latest estimates based on species distribution modelling and known densities put the population size at 3,800–6,500 individuals (C. Layusa and C. Oliveros in litt. 2012), equating to 2,500-4,300 mature individuals.

Trend justification: The population is suspected to be stable in the absence of evidence for any substantial declines or threats.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Philippines N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Hunting & trapping terrestrial animals Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Species mortality
Biological resource use Logging & wood harvesting Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases Timing Scope Severity Impact
Future Majority (50-90%) Rapid Declines Low Impact: 5
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases Timing Scope Severity Impact
Future Majority (50-90%) Rapid Declines Low Impact: 5
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases Timing Scope Severity Impact
Future Majority (50-90%) Rapid Declines Low Impact: 5
Stresses
Reduced reproductive success
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem conversion
Transportation & service corridors Roads & railroads Timing Scope Severity Impact
Future Majority (50-90%) Slow, Significant Declines Low Impact: 4
Stresses
Ecosystem degradation

Recommended citation
BirdLife International (2019) Species factsheet: Gallirallus calayanensis. Downloaded from http://www.birdlife.org on 22/11/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/11/2019.