Species

Justification
This species has an extremely small population within a tiny range. Its numbers were previously increasing as a result of concerted management efforts, however numbers are now thought to have reduced again owing to rat and cat predation and competition for nest hollows. A continuing decline is therefore precautionarily inferred, and the species has been uplisted to Critically Endangered once more.

Taxonomic source(s)
Christidis, L.; Boles, W. E. 2008. Systematics and taxonomy of Australian birds. CSIRO Publishing, Collingwood, Australia.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

Identification
30 cm. Green parrot with red crown. Sexes similar, but male slightly larger. Adult has red crown and frontal band, blue edging on wings and red eye. Juvenile has brown eye and light flesh-coloured beak. Voice Principal call loud kakakaka.

Cyanoramphus cookii is endemic to Norfolk Island (to Australia). It was once found throughout the island, and estimated to number at least 190 pairs. It is now confined to the Norfolk Island National Park and adjacent forested areas and orchards (Hill 2002). In 1994, the declining population consisted of only four breeding females and 28-33 males. Conservation management measures have allowed the population to grow, and numbers were estimated at a possible 200-300 individuals in 2004, and 150-200 birds in 2008. However, recent observations of disappearance from places where it was once common, and evi­dence of cat predation (M. Christian, R. Ward and J. Forshaw pers. comm., in Garnett et al. 2011) suggest the population may be declining again.

Population justification
An extrapolation based on banding and likely survivorship suggested that in 2008 the species had a population of 150-200 individuals (P. Olsen in litt. in Garnett et al. 2011), and a population of >240 individuals was estimated in 2009 based on 13 pairs recorded at point counts (G. Dutson pers. obs., in Garnett et al. 2011). The number of mature individuals is uncertain but is likely to be <250 (Garnett et al. 2011) and is placed here in the band 50-249 mature individuals.

Trend justification
Following a low of just 32 birds in 1988, the population increased rapidly to 200-300 individuals in 2005 owing to conservation management measures (R. Ward in litt. 2005). However, recent observations of disappearance from places where once common and evidence of cat predation suggest the population may be declining again (Garnett et al. 2011).

Ecology
It is restricted to forest, but visits orchards to feed on soft fruit. It also feeds on seeds, other fruits, flowers and leaves of both native and introduced trees and shrubs. It usually nests in tree-hollows, mostly in ironwood Nestegis apetala.


Threats
Clearance of forests before 1950, for timber, agriculture and pasture, severely reduced suitable habitat. Since then, increasing weed invasion has dramatically altered the structure and composition of remaining native vegetation. The degradation of native plant communities has been linked with a reduction in the nutrient input to the island, caused by the decimation of formerly large populations of burrow-nesting seabirds by introduced mammalian predators (Holdaway in prep.). Though forest clearance has stopped, recovery requires new habitat to become available. Nest-site availability has been further reduced by competition with introduced Crimson Rosella Platycercus elegans and, to a lesser extent, Common Starling Sturnus vulgaris and feral honey bees. Most known nest failures have resulted from predation by introduced black rats Rattus rattus. Feral cats are also thought to be significant predators and, although the level of predation is unquantified, anecdotal reports have been alarming (M. Christian in litt. 2007). There is a high level of Psittacine Circoviral Disease (PCD) in the population, which has resulted in some mortality.


Conservation actions underway
CITES Appendix I. The Norfolk Island National Park was declared in 1986, encompassing most of the main remaining stands of native trees on the island. Known and potential nest-sites are identified, monitored and protected, and introduced competitors using these sites are culled. Rat-proof nesting hollows are being installed in the national park. Over 600 chicks were banded during 1985-2007, most of which were bred and fledged from the national park's assisted wild breeding programme. The feasibility of an offshore breeding programme is being investigated. Rat baiting and cat trapping is occurring within park boundaries. Control measures for rats are budget-constrained (S. Garnett in litt. 2006) and limited to the protected area. Since 1992, responsible cat ownership has been encouraged, along with the promotion and subsidisation of neutering and assistance in containing cats and reducing their predatory behaviour (M. Christian in litt. 2007). In 2006, a proposal was put forward to eradicate cats and all rodent species from the entire island, or at least significant areas, and prevent their reintroduction (Holdaway in prep.). Ideas included the use of an exclosure in which mammalian predators, and probably alien plants, would be eradicated and burrow-nesting seabirds translocated (S. Garnett in litt. 2006) in an effort to increase nutrient supplies and thus rehabilitate native plant communities. However, no such project has so far been implemented or funded. The use of predator-proof fencing by the national park will be important in protecting the park's wildlife, reducing the island's rat population and reducing the reliance of householders on cats for rodent control (M. Christian in litt. 2007). The Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks 2010) recommends a set of recovery measures required to reduce or remove threats to native species on the island.

Conservation actions proposed

Monitor trends in population size and breeding success. Determine constraints on population growth and causes of breeding failure, and the effects of competition for nest hollows from Crimson Rosellas. Investigate effective methods for removing Crimson Rosellas given constraints on firearm use. Continue to identify, monitor and protect known and potential parrot nest sites, and destroy introduced competitors using these sites (particularly Crimson Rosellas) and/or install and maintain rat-proof nesting hollows in the National Park and on adjacent private land. Investigate feasibility of PCD immunisation.  Eliminate mammalian predators from the entire island, or at least significant sections, and prevent reintroduction (Director of National Parks 2010). Close captive-breeding facility and establish a breeding population, possibly at Taronga Park Zoo. Reintroduce birds to Phillip Island following provision of sufficient suitable habitat. Investigate establishing a population on the mainland and possible reintroduction to Lord Howe Island. Encourage government action over the responsible ownership of cats (M. Christian in litt. 2007). Eliminate mammalian predators from the entire island, or at least significant sections, and prevent reintroduction (Director of National Parks 2010).

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• Over ten years, action by BirdLife Partners and others prevented the extinction of 16 bird species

References
Garnett, S. T.; Crowley, G. M. 2000. The action plan for Australian birds 2000. Environment Australia, Canberra.

Boon, W. M.; Daugherty, C. H.; Chambers, G. K. 2001. The Norfolk Island Green Parrot and New Caledonian Red-crowned Parakeet are distinct species. Emu 101: 113-121.

Hill, R. 2002. Recovery plan for the Norfolk Island Green Parrot Cyanoramphus novaezelandiae cookii.

Garnett, S.T., Szabo, J.K. and Dutson, G. 2011. The Action Plan for Australian Birds 2010. CSIRO Publishing, Collingwood.

Director of National Parks. 2010. Norfolk Island Region Threatened Species Recovery Plan. Department of the Environment, Water, Heritage and the Arts, Canberra.

Further web sources of information
Alliance for Zero Extinction (AZE) species/site profile. This species has been identified as an AZE trigger due to its IUCN Red List status and limited range.

Australian Govt - Action Plan for Australian Birds 2000 - Recovery Outline

Click here for more information about the Alliance for Zero Extinction (AZE)

Text account compilers
Benstead, P., Garnett, S., McClellan, R., Pilgrim, J., Symes, A., Taylor, J.

Contributors
Christian, M., Garnett, S., Holdaway, R., Stevenson, P., Ward, R.

IUCN Red List evaluators
Butchart, S., Taylor, J.

Recommended citation
BirdLife International (2013) Species factsheet: Cyanoramphus cookii. Downloaded from http://www.birdlife.org on 24/05/2013. Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 24/05/2013.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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