EN
Golden White-eye Cleptornis marchei



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)+2ab(iii,v) B1ab(iii,v)+2ab(iii,v); D2

Red List history
Year Category Criteria
2020 Endangered B1ab(iii,v)+2ab(iii,v)
2016 Critically Endangered A3ce+4ce
2015 Critically Endangered A3e+4e
2012 Critically Endangered A3e+4e
2010 Critically Endangered A3e
2009 Critically Endangered A3e
2008 Critically Endangered
2004 Critically Endangered
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency Medium
Land mass type Average mass 20 g
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 3,100 medium
Extent of Occurrence breeding/resident (km2) 10
Number of locations 3 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 29000-70000 medium estimated 2020
Population trend Decreasing poor inferred -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) 10-19 - - -
Decline (10 years/3 generation past and future) 10-19 - - -
Number of subpopulations 3 - - -
Percentage in largest subpopulation 1-89 - - -

Population justification:

The species is considered to be abundant and widespread on Saipan, but less abundant on Aguiguan (MAC Working Group 2014).

On Saipan, surveys in 2007 provided an estimate of 71,997 individuals (95% CI 47,586 – 106,535), with a density of 711.8 ± 112.1 birds/km(Camp et al. 2009). Analysis of population densities indicated a decline between 1982 and 2007 (Camp et al. 2009) and analysis of data from roadside surveys from 1991-2010 indicated that the population decreased between 2001 and 2010 (Ha et al. 2018). Assuming that this trend has continued, the population on Saipan may now be expected to be smaller than in 2007. Based on the relative population densities recorded in 1997 (995.5 birds/km2; Camp et al. 2009) and 2007 (711.8 birds/km2; Camp et al. 2009), the abundance estimate from 2007 and assuming a constant rate of decline, the current population is estimated to be within the range 30,767 - 68,882 (best estimate: 46,551) individuals.

On Aguiguan, surveys in 2008 estimated 15,499 individuals (95% CI 10,383 - 22,277), with a population density of 2,433 ± 466 birds/km2 (Amidon et al. 2014). Analysis of population densities indicated an increase between 1982 and 2008 (Camp et al. 2012, Amidon et al. 2014). Assuming that this trend has continued, the population on Aguiguan may now be expected to be larger than in 2008. Based on the relative population densities recorded in 1995 (1,901 birds/km2; Amidon et al. 2014) and 2008 (2,433 birds/km2; Amidon et al. 2014), the abundance estimate from 2008, and assuming a constant rate of increase, the current population is estimated to be within the range 13,039 - 27,975 (best estimate: 19,463) individuals.

A third population was established on the uninhabited island of Sarigan through translocations of 24 and 50 individuals in 2011 and 2012, respectively, with breeding detected within the first year (Radley 2012, MAC Working Group 2014). There is no more recent population data for the population on Saigan at the time of assessment.

Based on the population sizes described above, the current total population on Saipan and Aguiguan is estimated to be within the range 43,806 - 96,857 (best estimate: 66,014) individuals, which roughly equates to 29,204-64,571 (44,009) mature individuals. There is now an additional small population on Sarigan. The total population size is therefore placed in the band 29,000 - 70,000 mature individuals.

There are three subpopulations, one on each range island.



Trend justification:

On Saipan, surveys by Engbring et al. (1986) in 1982 using point-transect methods estimated the population at 55,500 individuals. Further surveys were carried out in 1997 (USFWS 1998) and 2007 (Camp et al. 2009). The 2007 survey provided an estimate of 71,997 individuals (95% CI 47,586 – 106,535; Camp et al. 2009). Despite the larger population estimate in 2007, the population density was found to have declined from 1,287.3 ± 191.0 birds/km2 in 1982 to 995.5 ± 160.0 birds/kmin 1997 and to 711.8 ± 112.1 birds/kmin 2007 (Camp et al. 2009). The difference between the population estimates in 1982 and 2007 was attributed to a difference in the statistical methods used to estimate population size (Camp et al. 2009). Analysis of data from roadside surveys from 1991-2010 indicated that the population has increased from 1991-2000, then decreased between 2001 and 2010 (Ha et al. 2018).

On Aguiguan, surveys using point-transect methods in 1982 resulted in a population estimate of 2,300 individuals (Engbring et al. 1986). The transects were resurveyed in 1992 (Craig et al. 1993), 1995, 2000 (Cruz et al. 2000), 2002 (Esselstyn et al. 2003) and 2008 (Camp et al. 2012, Amidon et al. 2014). All surveys followed standard point-transect methods. The 2008 surveys estimated 15,499 individuals (95% CI 10,383 - 22,277; Amidon et al. 2014). Density estimates were as follows: 1,094 ± 196 birds/km2 in 1982; 1,901 ± 382 birds/kmin 1995; 2,224 ± 396 birds/kmin 2000; 1,693 ± 275 birds/km2 in 2002, and 2,433 ± 466 birds/kmin 2008 (Amidon et al. 2014). The population density increased significantly between 1982 and 2008 (Camp et al. 2012, Amidon et al. 2014). 

A third population was established on the uninhabited island of Sarigan through translocations of 24 and 50 individuals in 2011 and 2012, respectively, with breeding detected within the first year (Radley 2012, MAC Working Group 2014).

Although the population size appeared to be increasing on Aguiguan (Camp et al. 2012, Amidon et al. 2014), and a new population has been established on Sarigan (Radley 2012, MAC Working Group 2014), the largest subpopulation, on Saipan, was found to be decreasing (Camp et al. 2009, Ha et al. 2018) and overall, the species is inferred to be undergoing a continuing decline in population size.

Based on the relative population densities recorded in Saipan in 1997 and 2007, the relative population densities recorded in Anguiguan in 1995 and 2008, the abundance estimates from 2007 (Saipan) and 2008 (Aguiguan), and assuming that the population on Sarigan has no more than 100 individuals, and that rates of population change have remained constant, the total population is suspected to have undergone a reduction of 10-19% over the past ten years. Assuming the trend continues over the next decade, the population is also suspected to undergo a reduction of 10-19% over the next three generations.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Northern Mariana Islands (to USA) N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Northern Mariana Islands (to USA) Aguiguan Island and Naftan Rock
Northern Mariana Islands (to USA) Northern Saipan
Northern Mariana Islands (to USA) Topachau-Susupe-Kagman

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Plantations suitable resident
Artificial/Terrestrial Subtropical/Tropical Heavily Degraded Former Forest suitable resident
Artificial/Terrestrial Urban Areas suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Shrubland Subtropical/Tropical Moist suitable resident
Altitude   Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Unknown Unknown
Stresses
Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather Storms & flooding Timing Scope Severity Impact
Past, Likely to Return Majority (50-90%) No decline Past Impact
Stresses
Ecosystem degradation
Geological events Volcanoes Timing Scope Severity Impact
Past, Likely to Return Minority (<50%) Very Rapid Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Boiga irregularis Timing Scope Severity Impact
Past, Likely to Return Whole (>90%) Very Rapid Declines Past Impact
Stresses
Indirect ecosystem effects, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Capra hircus Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Coccinia grandis 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 - Lantana camara Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Reduced reproductive success, Species mortality
Residential & commercial development Commercial & industrial areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2021) Species factsheet: Cleptornis marchei. Downloaded from http://www.birdlife.org on 02/12/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 02/12/2021.