CR
Palila Loxioides bailleui



Taxonomy

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
B1ab(iii,v) A2bce+3bce+4bce; B1ab(iii,v)+2ab(iii,v); C1+2a(ii) A2bce+3bce+4bce; B1ab(iii,v)+2ab(iii,v); C1+2a(i,ii); D1+2

Red List history
Year Category Criteria
2023 Critically Endangered B1ab(iii,v)
2016 Critically Endangered A4bce
2015 Critically Endangered A4bce
2012 Critically Endangered A4bce
2011 Critically Endangered A4b,c,e
2010 Critically Endangered A4b,c,e
2009 Critically Endangered A4b,c,e
2008 Endangered
2004 Endangered
2000 Endangered
1996 Endangered
1994 Endangered
1988 Threatened
Species attributes

Migratory status not a migrant Forest dependency high
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 80 km2 good
Area of Occupancy (breeding/resident) 80 km2
Number of locations 1 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 800-1200, 970 mature individuals good estimated 2022
Population trend decreasing good estimated 2015-2027
Rate of change over the past 10 years/3 generations (longer of the two periods) 50-60% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 50-60% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 50-60% - - -
Generation length 4.17 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: In 2021 the population was estimated at 452?940 individuals (point estimate of 678), with previous estimates of 1,030?1,899 individuals (point estimate of 1,432) in 2019, and 964?1,700 individuals (point estimate of 1,312) in 2020 (Genz et al. 2022). Although 2021 abundance estimates are approximately 50% of 2020 estimates, this is considered biologically unlikely and previous low estimates from annual surveys in 2000, 2010 and 2015 have been immediately followed by an increase in subsequent years (Genz et al. 2022). The five-year average (2017-2021) population size is 1,128 individuals, and based on an approximate estimate that 86% are mature individuals (C. Farmer in litt. 2016) this equates to 970 mature individuals. The population size is therefore tentatively placed in the range 800-1,200 mature individuals.

Trend justification: During 1998?2005, estimates fluctuated between 4,000 and 6,000 individuals, followed by a steep decline - between 2005 and 2008 the population fell from c.5,500 to c.1,800 individuals (Genz et al. 2022). This steep decline levelled off somewhat after 2010, but trend assessments show that the population has continued to decline, leading to a record low in 2021 (Genz et al. 2022). The mean decline during 1998?2021 was 229 individuals per year, resulting in an 89% decline in the population over the entire 23-year monitoring period (Genz et al. 2022), equivalent to c.70% within three generations. Within the most recent three-generation period (12.5 years; Bird et al. 2020), annual surveys indicate that the population declined by approximately 50-60% (Genz et al. 2022) and this is thought to continue given that the threats are ongoing. Although the size of the overall area containing detections of the species has not shown substantial change since 1998 (Genz et al. 2022), there has reportedly been a decline of detections within sections of this area which has continued in the 2022-2023 annual surveys (C. Farmer in litt. 2023).


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

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
USA Mauna Kea Mamane - Naio Forest

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Dry major resident
Forest Subtropical/Tropical Moist Montane major resident
Altitude 2000 - 3000 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Past, Unlikely to Return Majority (50-90%) Slow, Significant Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Climate change & severe weather Droughts Timing Scope Severity Impact
Ongoing Whole (>90%) Rapid Declines High Impact: 8
Stresses
Ecosystem degradation, Reduced reproductive success
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Slow, Significant Declines Low Impact: 5
Stresses
Species mortality
Climate change & severe weather Storms & flooding Timing Scope Severity Impact
Future Whole (>90%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation, Reduced reproductive success
Climate change & severe weather Temperature extremes Timing Scope Severity Impact
Future Whole (>90%) Unknown Unknown
Stresses
Reduced reproductive success, Species mortality
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Species disturbance, Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Armillaria mellea Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Asio flammeus Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Bos taurus Timing Scope Severity Impact
Past, Unlikely to Return Minority (<50%) Slow, Significant Declines Past Impact
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Buteo solitarius Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Capra hircus Timing Scope Severity Impact
Past, Unlikely to Return Majority (50-90%) Slow, Significant Declines Past Impact
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Cenchrus setaceus Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Dactylis glomerata Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Delairea odorata Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Klambothrips myopori Timing Scope Severity Impact
Ongoing Unknown Unknown Unknown
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Linepithema humile Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Ovis aries Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Ovis gmelini Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Plasmodium relictum Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Ulex europaeus Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Unspecified species Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Vespula germanica Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Vespula pensylvanica Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition
Invasive and other problematic species, genes & diseases Viral/prion-induced diseases - Avipoxvirus Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Species mortality
Natural system modifications Fire & fire suppression - Increase in fire frequency/intensity Timing Scope Severity Impact
Past, Likely to Return Whole (>90%) Rapid Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2024) Species factsheet: Palila Loxioides bailleui. Downloaded from https://datazone.birdlife.org/species/factsheet/palila-loxioides-bailleui 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.