||Zosterops natalis Lister, 1889
||Christmas White-eye, Christmas Island White-eye
||Christidis, L. and Boles, W.E. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Australia.
||11-13 cm. Small, warbler-like bird lacking bright yellow colouring. Sexes alike. Dull green above, greyish-white below. White eye-ring. Dull brownish primaries, secondaries and tail, edged green. Black lores, continuing to halfway under eye-ring. Bright chestnut iris in adults, grey in juveniles. Pale yellow undertail-coverts. Black bill, pale grey base to lower mandible. Similar spp. Vagrant Arctic Warblers Phylloscopus borealis are possible. Voice Variable, includes chirping, twittering. Hints Smallest bird in range. Flocks forage in all levels of vegetation.
|Red List Category & Criteria:
||Butchart, S. & Symes, A.
||Blyth, J., Garnett, S., Green, P., Hennicke, J., James, D., Low, T. & O'Dowd, D.
||Benstead, P., Garnett, S., McClellan, R., Pilgrim, J., Symes, A. & Taylor, J.
This species has been downlisted to Near Threatened because although it has a very restricted range, it is abundant and the population is estimated to be stable despite the presence of several invasive species. It is not classified as Vulnerable as there is not thought to be any plausible threat which is likely to cause rapid future declines.
|Previously published Red List assessments:|
- 2013 – Near Threatened (NT)
- 2012 – Near Threatened (NT)
- 2008 – Vulnerable (VU)
- 2006 – Vulnerable (VU)
- 2004 – Vulnerable (VU)
- 2000 – Critically Endangered (CR)
- 1994 – Lower Risk/near threatened (LR/nt)
- 1988 – Lower Risk/least concern (LR/lc)
|Range Description:||Zosterops natalis was confined to Christmas Island (Australia), in the Indian Ocean, until some time between 1885 and 1900, when it was introduced to Cocos Keeling Islands (to Australia). On Christmas Island, it is the most abundant bird species, numbering c.20,000 individuals, and is believed to be stable (S. Garnett in litt. 2005, Garnett et al. 2011). On Cocos-Keeling Islands, it apparently persists only around the settlement. On Christmas Island it forages over virtually all of the 137 km2 (D. James in litt. 2007). Surveys in 2005 and 2006 confirmed the species's high abundance, with the species recorded during 99% of counts and at 100% of survey sites (James and Retallick 2007). |
Cocos (Keeling) Islands
|♦ Continuing decline in area of occupancy (AOO):||Unknown|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||29500|
|♦ Continuing decline in extent of occurrence (EOO):||Unknown||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||2||♦ Continuing decline in number of locations:||Unknown|
|♦ Extreme fluctuations in the number of locations:||No|
|Range Map:||Click here to open the map viewer and explore range.|
Approximately a third of forested habitat has been destroyed on Christmas Island as a result of mining operations. The species appears to tolerate a degree of habitat modification. In 2007, significant patches of mature secondary forest were cleared for mining (D. James in litt. 2007). Also in 2007, a new application to mine a 250 ha area of rainforest (P. Green in litt. 2007) was turned down (J. Hennicke in litt. 2007), but has since gone to appeal (D. James in litt. 2007). The introduced yellow crazy ant Anoplolepis gracilipes, which formed super-colonies during the 1990s and spread rapidly to cover about 25% of the island or about 3,400 ha, but was controlled over about 2,900 ha in September 2002, was thought to be a potential threat. In 2006, the ants were regarded as widespread and patchily common (T. Low in litt. 2006). It was thought that ants might prey directly on nestlings, and that they would alter island ecology by killing the dominant life-form, the red crab Gecaroidea natalis, which otherwise inhibits understorey plant growth and the spread of weeds by eating the seeds and seedlings of both native and invasive species (P. Green and D. O'Dowd in litt. 2003, S. Garnett in litt. 2003, D. James in litt. 2007). Fears that the white-eye would be affected by the ants appear to have been proved wrong however: counts and foraging success of the white-eye were higher in places where ants were present, because of an increase in scale insects (Garnett et al. 2011). Black Rats Rattus rattus and feral cats Felis catus are present but are not currently thought to be causing declines (Garnett et al. 2011).