CR
Rota White-eye Zosterops rotensis



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.
Slikas, B.; Jones, I. B.; Derrickson, S. R.; Fleischer, R. C. 2000. Phylogenetic relationships of Micronesian white-eyes based on mitochondrial sequence data. The Auk 117: 355-365.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
B1ab(i,ii,iii)+2ab(i,ii,iii) B1ab(i,ii,iii)+2ab(i,ii,iii) B1ab(i,ii,iii)+2ab(i,ii,iii); D2

Red List history
Year Category Criteria
2017 Critically Endangered B1ab(i,ii,iii)+2ab(i,ii,iii)
2016 Critically Endangered B1ab(i,ii,iii,v)+2ab(i,ii,iii,v)
2013 Critically Endangered B1ab(i,ii,iii,v)+2ab(i,ii,iii,v)
2012 Critically Endangered B1ab(i,ii,iii,v)+2ab(i,ii,iii,v)
2010 Critically Endangered B1a+b(i,ii,iii,v); B2a+b(i,ii,iii,v)
2009 Critically Endangered B1a+b(i,ii,iii,v); B2a+b(i,ii,iii,v)
2008 Critically Endangered
2004 Critically Endangered
2000 Critically Endangered
1996 Critically Endangered
1994 Critically Endangered
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency High
Land mass type Average mass -
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 8 medium
Extent of Occurrence breeding/resident (km2) 3
Number of locations 1 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 3750-14000 good estimated 2012
Population trend Increasing medium estimated -
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 1 - - -
Percentage in largest subpopulation 100 - - -
Generation length (yrs) 3.5 - - -

Population justification:

In 1982, the species was estimated to have a population of 8,741–18,487 individuals (Engbring et al. 1986). Since then, surveys have estimated 300-1,500 birds in 1990 (Craig and Taisacan 1994), 1,165 birds in 1996, with 94% of the population restricted to four patches of forest covering only 259 ha (Fancy and Snetsinger 2001), and 1,092 birds in 1999 (Amidon 2000, Williams 2004). Thus the population rapidly declined between 1982 and 1999, but the population has stabilised or increased since the 1990s (F. Amidon in litt. 2007, 2010, 2011, Zarones et al. 2013) and returned to 1980s levels to an estimated population of 5,620-20,961 individuals in 2012 (Camp et al. 2015). This is roughly equivalent to 3,750-14,000 mature individuals.



Trend justification: A decline of 50-79% over three generations (10.5 years) was estimated based on a decline from 10,763 in 1982 to 1,092 in 1999 (Williams 2004). The population has stabilised or increased since the 1990s (F. Amidon in litt. 2007, 2010, 2011, Zarones et al. 2013) and returned to 1980s levels by 2012 (Camp et al. 2015), so the current trend is assessed as increasing over the past 3 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) Rota

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Altitude 100 - 490 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion
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
Ongoing Whole (>90%) Slow, Significant Declines Medium Impact: 7
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Boiga irregularis Timing Scope Severity Impact
Future Whole (>90%) Rapid Declines Medium Impact: 6
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Dicrurus macrocercus Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Reduced reproductive success
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Aplonis opaca Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Reduced reproductive success
Invasive and other problematic species, genes & diseases Problematic native species/diseases - Corvus kubaryi Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Reduced reproductive success
Pollution Agricultural & forestry effluents - Herbicides and pesticides Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2022) Species factsheet: Zosterops rotensis. Downloaded from http://www.birdlife.org on 04/10/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 04/10/2022.