Justification of Red List Category
This charismatic species is believed to be declining because of predation by, and competition with, various introduced mammals. It is widely acknowledged that it is very hard to accurately estimate its population size; however, the estimates available generally indicate that the population could be small. For these reasons it is listed as Vulnerable. Now that a monitoring method has been devised, it is hoped that current trend and population estimates can be improved upon.
The population has been estimated to number c.5,000 individuals (Peat 1994, Heather and Robertson 1997), on which basis the number of mature individuals is put at 3,300, although up-to-date survey data are required.
The population is a fraction of what it once was. One study detected an apparent decrease in numbers over 30 years at one site (Wilson and Brejaart 1992). It is now suspected to be declining overall, because of predation by, and competition with, various introduced mammals.
Nestor notabilis occurs in Marlborough and from Nelson to Fiordland on South Island, New Zealand. The population is a fraction of what it once was. Estimates are: 1,000-5,000 (Anderson 1986); c.15,000 (Bond and Diamond 1992); and 5,000 individuals (Peat 1994, Heather and Robertson 1997). One study detected an apparent decrease in numbers over 30 years at one site (Wilson and Brejaart 1992), although numbers in the St Arnaud range in the north of the South Island remained stable during the period 1992-1999 (Elliot and Kemp 2004).
It mostly inhabits high-altitude forest and alpine basins, although birds will often frequent lowland flats. It mostly feeds on berries and shoots, although many have adapted to feeding at refuse dumps and ski-fields. It nests in holes, under logs or in rocky crevasses. It usually lays four eggs. Males feed the females during incubation and after hatching. Birds breed after three or more years. The oldest recorded bird was over 20 years of age (Heather and Robertson 1997).
Up until its protection in 1970, over 150,000 were shot in a bounty scheme, established because rogue individuals were found to be attacking sheep as a source of fat. Introduced mammals such as stoats Mustela erminea, cats and brush-tailed possums Trichosurus vulpecula have spread into most of the species's range, but the extent of predation is unknown, although it may be significant (Wilson and Brejaart 1992, Peat 1994), and likely to increase in areas that possums have only recently colonised (Elliot and Kemp 2004). Trichosurus vulpecula, thar Hemitragus jemlahicus, red deer Cervus elaphus, hare Lepus europaeus, chamois Rupicapra rupicapra and pastoral farming practices may also be depleting crucial winter foods (Wilson and Brejaart 1992, A. Grant in litt. 1999). Deforestation for pasture has placed pressure on the species, and farmers still kill an unknown number of birds each year (Mosen 2009). It is suspected that some birds are poisoned by toxins and other hazardous material scavenged from rubbish dumps and sites of human occupation (A. Grant in litt. 1999). Both lead toxins and the 1080 toxin used in invasive control have potentially widespread impacts on the population (T. Orr-Walker in litt. 2008). Climate change may pose a threat through possible future influences on its high altitude habitat (Mosen 2009).
Conservation Actions Underway
CITES Appendix II. Research is being conducted on its ecology and population dynamics. Advocacy is aimed at informing alpine users of ways to minimise adverse impacts and to change the negative image of the species often held by high-country farmers and ski-field operators (A. Grant in litt. 1999).
48 cm. Inquisitive alpine parrot. Olive-green with scarlet underwings and rump. Dark-edged feathers. Dark brown bill, cere, iris, legs and feet. Male has longer bill. Juvenile has yellow cere, eye-ring and on bill. Similar spp. Kaka N. meridionalis is a lowland species, smaller, darker with crimson underparts. Voice Loud keee-aa.
Text account compilers
Benstead, P., Bird, J., Khwaja, N., McClellan, R., Pilgrim, J., Taylor, J.
Grant, A., Orr-Walker, T.
BirdLife International (2017) Species factsheet: Nestor notabilis. Downloaded from http://www.birdlife.org on 17/10/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 17/10/2017.