CR
Maui Parrotbill Pseudonestor xanthophrys



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(i,ii,iii,v); C1 A2bce+3bce+4bce; B1ab(i,ii,iii,v)+2ab(i,ii,iii,v); C1; D A2bce+3bce+4bce; B1ab(i,ii,iii,v)+2ab(i,ii,iii,v); C1; D1+2

Red List history
Year Category Criteria
2023 Critically Endangered B1ab(i,ii,iii,v); C1
2016 Critically Endangered B1ab(iii)
2015 Critically Endangered B1ab(iii)
2013 Critically Endangered B1ab(iii)
2012 Critically Endangered B1ab(iii)
2010 Critically Endangered B1a+b(iii)
2009 Critically Endangered B1a+b(iii)
2008 Critically Endangered
2004 Critically Endangered
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
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) 70 km2 medium
Area of Occupancy (breeding/resident) 40 km2
Number of locations 1 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 105 mature individuals medium estimated 2017
Population trend decreasing poor estimated 2017-2027
Rate of change over the past 10 years/3 generations (longer of the two periods) 60-70% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 60-70% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 60-70% - - -
Generation length 2.81 years - - -
Number of subpopulations 2 - - -
Percentage of mature individuals in largest subpopulation 1-89% - - -

Population justification: During 1976-1983, it was estimated to number c.500 individuals, of which 71% (c. 355) occurred above 1,500 m (Scott et al. 1986). Density surveys in 1997 and 2001 suggested similar numbers in the 35 km2 of remaining suitable habitat above 1,525 m (Simon et al. 1997, D. Leonard in litt. 2012). The total population size was estimated to number 513 ± 143 individuals in 1980, 447 ± 157 in 1992, 544 ± 153 in 2001 and 291 ± 69 in 2011 (Judge et al. 2021). Overall density was even lower in 2017 (0.05 ± 0.02 birds/ha), with an estimated total abundance of 157 ± 67 (95% CI 44–312) individuals in their 2,992 ha range (Judge et al. 2021). This is roughly equivalent to 105 mature individuals.

Trend justification: Since 2001 the population has declined by approximately 71%  to 157 ± 67 individuals in 2017 (Judge et al. 2021). Surveys suggest a c.46% decline in the period 2011-2017, roughly equivalent to 64% in ten years (Judge et al. 2021), and this is thought to be continuing given that the threats are ongoing. The current rate of decline is therefore placed in the band 60-70% in ten years. The current estimated range is projected to decline by >75% by 2100 according to climate-based models (Fortini et al. 2015), although the population is likely to become functionally extinct in as few as ten years if current population trajectories continue (Mounce et al. 2018).


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 Haleakala

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Montane major resident
Altitude 1200 - 2350 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Livestock farming & ranching - Agro-industry grazing, ranching or farming Timing Scope Severity Impact
Past, Unlikely to Return Majority (50-90%) Slow, Significant Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Unintentional effects: (large scale) [harvest] 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 Habitat shifting & alteration Timing Scope Severity Impact
Ongoing Whole (>90%) Slow, Significant Declines Medium Impact: 7
Stresses
Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Axis axis Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Capra hircus Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
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%) Negligible declines Low Impact: 4
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Hedychium gardnerianum Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Herpestes auropunctatus Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Competition, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Plasmodium relictum Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Psidium cattleianum Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Sus domesticus Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Indirect ecosystem effects, 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, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Unspecified species Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Competition, Species mortality
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Asio flammeus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Viral/prion-induced diseases - Avipoxvirus Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species mortality

Recommended citation
BirdLife International (2024) Species factsheet: Maui Parrotbill Pseudonestor xanthophrys. Downloaded from https://datazone.birdlife.org/species/factsheet/maui-parrotbill-pseudonestor-xanthophrys on 23/12/2024.
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 23/12/2024.