Justification of Red List Category
This cryptic species endemic to Australia was rediscovered in western Queensland in 2013 after a 78-year period without a confirmed record. Since then, at least two additional populations and areas have been identified in Western Australia. Population size, trends, and geographic range are still very poorly understood. The population size has been placed in the band of 50-249 mature individuals, and for this reason it is classified as Endangered.
The size of the currently known population has not been estimated, but it is assumed that the number of mature individuals is in the band 50-249 (per Garnett et al. 2011), but may prove to be larger.
The quality of the species's habitat is suspected to be in decline owing to a combination of pervasive threats.
This nocturnal parrot is endemic to Australia. Though cryptic, it was frequently seen and collected in the late nineteenth century (Murphy et al. 2017). However, after an individual was collected in Western Australia in 1912, there was no confirmed sighting for 78 years. Then, in 1990, a dead body of the night parrot was discovered on a roadside in western Queensland (Boles 1994). Another body was found less than 200 km away in 2006, suggesting the existence of a population in the region (McDougall et al. 2009). A population was discovered in 2013, and photographs and sound recordings were produced (Dooley 2013). This population, located in Pullen Pullen Reserve in the Goneaway Tableland subregion in western Queensland, has become the focus of research into the breeding, movements, and ecology of the species. Additional populations have been confirmed in the East Murchison and Great Sandy Desert areas of Western Australia (Jackett et al. 2017, Kimberley Land Council 2019).
Reports of feathers and calls in Kalamurina Wildlife Sanctuary in South Australia have been retracted, so the existence and extent of a population there remains unconfirmed (Australian Wildlife Conservancy 2019). The status of a population in Diamantina National Park, adjacent to the well-studied Pullen Pullen Reserve, remains similarly unresolved: research is ongoing there (Leseberg 2019), but some reports have been retracted (Australian Wildlife Conservancy 2019).
In an attempt to explain widespread but scattered records, the species was previously thought to be nomadic or to have very large home ranges (Higgins 1999). However, limited radio- and GPS-tracking carried out by Murphy et al. (2017b) implies that the species is more sedentary than these speculations suggest. Movement of two tracked birds remained within an area of approximately 70 km2. Individuals moved approximately 30 km per night within a radius of less than 10 km from roosting locations.
Tracked birds moved from their roosts in Triodia (spinifex) hummocks to feeding sites in more diverse habitats marked by large-seeded grass and forb species. Physiological modelling suggests that the species may need to visit standing water, especially during summer (Kearney et al. 2016). The bird GPS-tracked by Murphy et al. (2017b) only visited a permanent water source once. However, a considerable amount of rain fell during the tracking period, and so ephemeral water sources were likely to be available. During winter, Night Parrots may satisfy water requirements from their diet, which may include succulent plants, such as Sclerolaena spp (Kearney et al. 2016).
Most habitat records are of Triodia grasslands and/or chenopod shrublands (Garnett et al. 2011) in the arid and semi-arid zones, and Higgins (1999) listed Astrebla spp. (Mitchell grass), shrubby samphire and chenopod associations, scattered trees and shrubs, Acacia aneura (Mulga) woodland, treeless areas and bare gibber as associated with sightings of the species. S. Murphy (pers. comm. in TSSC 2016) recorded a similar range of habitats used or traversed by individuals in southwestern Queensland: Cretaceous sandstone, claystone, and siltstone residuals; either dominated by Triodia longiceps on slopes and margins of duricrust plateaus or with Sclerolaena spp., Maireana spp. (Saltbush spp.), Ptilotus spp. (Mulla Mulla spp.), and small areas of T. longiceps; with occasional watercourses with Acacia cambagei (stinking gidgee). The habitat of the southwestern Queensland population is naturally fragmented, and is unlikely to promote fire behaviour that results in most habitat in this area being burned by one fire event (Murphy 2015, S. Murphy pers. comm. 2016 in TSSC 2016).
Recent and historical accounts of nests describe a slight depression in a cavity at the end of a tunnel built into a Triodia hummock (Hamilton et al. 2017, Murphy et al. 2017a). Clutch size is reported as 2-4 eggs (Murphy et al. 2017a, Collar et al. 2019).
The causes of the assumed decline of the species are “essentially guesswork” (Garnett et al. 2011). Blyth (1996) proposed a list of threats considered realistic in the absence of direct evidence. Threats to the species are likely to vary across its range and might include predation by feral cats and foxes; soil disturbance, erosion and loss caused by herbivores (including livestock and over-abundant native and feral herbivores); degradation of habitat around water points by herbivores; competition for food by herbivores; fire; psittacine beak and feather disease, avian pox, and other diseases; illegal collection of birds or eggs; disturbance from bird-watching activities; fences; and reduction in water availability through over-use of waterholes by camels and reduced waterhole maintenance (TSSC 2016). Biophysical modelling suggests that predicted temperature increases under various climate change scenarios would increase the species's dependence on free-standing water dramatically (Kearney et al. 2016). Thus, climate change, interacting with the spatial configuration of water points and habitats, and the concentration of feral predators at water points, may become a serious future threat.
Conservation Actions Underway
CITES Appendix I. The recent discovery of a small population in 2013 has led to an intensive conservation and research programme, now directed towards the conservation actions proposed below, from TSSC (2016).
22-25 cm. Short-tailed, dumpy parrot. Sexes alike. Adult predominantly green, grading to yellow underparts, with extensive fine black markings. Mainly dark grey upperwing with narrow, pale yellow wing-bar. Grey-green underwing with broad wing-bar. Juvenile probably similar but duller. Similar spp. Distinguished from Budgerigar Melopsittacus undulatus by larger size, shorter tail, terrestrial nature and furtive nocturnal habits - but note that quite a few records of Night Parrots are from the day time, especially if flushed. Superficially similar Ground Parrot Pezoporuswallicus has longer tail and different range and habitat. Voice Said to have low, two-note or drawn-out whistle, audible at a distance; and a frog-like croak.
Text account compilers
Smith, D., Symes, A., Butchart, S., Bird, J., Benstead, P., Garnett, S., McClellan, R.
Bamford, M.J., Burbidge, A.H., Joseph, L., Metcalf, B.M. & Murphy, S.
BirdLife International (2021) Species factsheet: Pezoporus occidentalis. Downloaded from http://www.birdlife.org on 23/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 23/10/2021.