Australian Field 2019, 36, 79–88 http://dx.doi.org/10.20938/afo36079088

Descriptions of known vocalisations of the Night occidentalis

Nicholas P. Leseberg1, 2*, Stephen A. Murphy1, 2, 3, Nigel A. Jackett4, Bruce R. Greatwich5, Jamie Brown6, Neil Hamilton7, Leo Joseph8 and James E.M. Watson1, 2

1School of Earth and Environmental Sciences, University of , St Lucia QLD 4072, 2Green Fire Science, , St Lucia QLD 4072, Australia 3 Adaptive NRM, P.O. Box 93, Malanda QLD 4885, Australia 4Environs Kimberley, P.O. Box 2281, Broome WA 6275, Australia 5Department of Biodiversity, Conservation and Attractions, P.O. Box 65, Broome WA 6725, Australia 6Paruku Rangers, Land and Sea Management Unit, P.O. Box 8252, Broome WA 6275, Australia 7Department of Biodiversity, Conservation and Attractions, Woodvale Research Centre, Locked Bag 104, Bentley Delivery Centre, Bentley WA 6983, Australia 8Australian National Wildlife Collection, National Research Collections Australia, CSIRO, Canberra ACT 2601, Australia *Corresponding author. Email: [email protected]

Abstract. Until recently, the only descriptions of Pezoporus occidentalis vocalisations were anecdotal reports from observers in the late 19th and early 20th centuries. The 2013 discovery of an extant population of Night in western Queensland led to the first contemporary descriptions, and further calls were described following the 2017 discovery of Night Parrots at a site in central . Ongoing field studies have shown that the species has a complex repertoire and, although there are some similarities in vocalisations between sites, there is much spatial and temporal variation. It is likely that call recognition will be the primary means of detection for this cryptic species, underscoring the importance of cataloguing vocalisations across the species’ range. Accordingly, we describe all known vocalisations from the three sites where Night Parrots are known to occur.

Introduction from an adult gave squawking calls (Wilson 1937). Murphy et al. (2017a) and Jackett et al. (2017) provided the first contemporary descriptions of Night Parrot vocalisations. The Night Parrot Pezoporus occidentalis was first recorded These authors described several vocalisations recorded by Europeans in 1845 (Sturt 1845). Despite occurring around active nests in western Queensland and central throughout largely uninhabited arid central Australia, it had Western Australia, respectively. Calls described from all but vanished by the early 20th century (Higgins 1999). Queensland included peel, chirrup and prat calls, a croak Multiple searches throughout the 20th century (e.g. White call that was apparently a contact call between individuals, 1913; Whitlock 1924) found little evidence of the Parrot’s and three vocalisations with a bell-like quality—dink-dink, continued existence, although a trickle of unconfirmed ding-de-ding and dee-de-dee-de. From Western Australia, reports and rumours hinted at its persistence (e.g. Powell croak was reported, along with a hollow whistle and didit 1970; Parker 1980). In 1990, the discovery of a dead call. Night Parrot beside a road in western Queensland (Boles et al. 1994) provided irrefutable proof that the species Since the Night Parrot’s rediscovery, intensive research was extant, and in 2006 another dead , an immature in western Queensland has focused on its ecology (Murphy female, was found in western Queensland (Cupitt & Cupitt et al. 2017a,b). The roost and breed in patches of long- 2008; McDougall et al. 2009). In 2013, naturalist John unburnt spinifex longiceps, apparently as dispersed Young provided evidence of an extant population of Night pairs or small family groups. After sunset, they depart from Parrots in western Queensland, including the first known their roosting areas and spend the night foraging, returning recordings of the bird’s call (Koch 2013; Olsen 2018). In to their roost before sunrise. Each night before departure, 2017, Night Parrots were detected at two sites in Western and again in the morning following return to their roosting Australia (Hamilton et al. 2017; Jackett et al. 2017; Mills & sites, the birds engage in predictable periods of calling Collins 2017). that continue year-round (SAM, NPL unpubl. data). These calling periods occur in the first hour after sunset and in The historical literature contains few descriptions of Night the 2 hours before sunrise. The calling periods are brief, Parrot vocalisations. Various whistling calls are reported, sometimes lasting only a few minutes (SAM, NPL unpubl. including “a plaintive whistling note” (Mallee Bird 1908, data). In addition to these predictable calling periods, Night p. 52; Menkhorst & Ryan 2015, p. 109), a “sweet low two- Parrots call more frequently during breeding, when calling note whistle” (McGilp 1931, p. 70), and a “long drawn-out at roosting/breeding sites occurs throughout the night. mournful whistle” (Wilson 1937, pp. 83–84). Both McGilp Birds also call occasionally at their feeding sites and when (1931) and Wilson (1937) reported that whistling calls visiting standing water (SAM, NPL, JB unpubl. data). were given in flight. Andrews (1883, p. 29) described Night Parrots giving a “very peculiar croaking note” resembling Preliminary research from both sites in Western the “loud croak of a frog” when alarmed, and Bourgoin Australia indicate that calling behaviour is similar to reported that a flushed bird uttered a “squeak, as if it were that in western Queensland. Some vocalisations are hurt” (Wilson 1937, p. 83). Young birds begging for food also similar, whereas others appear to be unique 80 Australian Field Ornithology N.P. Leseberg et al.

(Jackett et al. 2017; JB pers. comm.). Given the Night flushing in and around known Night Parrot populations, Parrot’s extremely cryptic habits, this predictable calling making attribution of unknown vocalisations difficult. Night behaviour is likely to provide the most reliable method Parrots have never been directly observed giving some of of detection, as it does for its closest congeners the the calls described in this paper, but in each case a call Pezoporus wallicus and Western has been heard multiple times and/or in association with Ground Parrot P. flaviventris (Burbidge et al. 2007). For other calls known to be Night Parrot calls. Although it is this reason, a complete catalogue of known Night Parrot extremely unlikely that any of the vocalisations described calls will provide an important tool for further survey work, herein are of any species other than the Night Parrot, we necessary to improve our knowledge of the species’ acknowledge a low probability that a vocalisation has been distribution and status. mistakenly attributed to the Night Parrot. There have been several recent reports of possible Night Parrot calls from locations throughout Australia (e.g. Beaven 2017; Ison 2017). Although it is possible that Results some of these calls are of Night Parrots, there are only Descriptions of known Night Parrot three regions where the presence of the species has been vocalisations confirmed visually (sighting or photograph) and calls have been heard or recorded under circumstances that make it We describe all known vocalisations here in four extremely unlikely that they are of any species other than categories: whistles, bell-like calls, croaks, and nestling/ the Night Parrot. These regions are the Channel Country fledgling calls. Key information for all whistle, bell-like and of western Queensland, the East Murchison district of croak calls is presented in Table 1 and for other calls below. central Western Australia, and the of Spectrograms of all whistle and bell-like calls, and croak northern Western Australia. This paper collates existing are presented (Figures 1–11). In some cases, the same data from these regions at the time of writing (January spectrogram shows different calls recorded at different 2019), and provides descriptions of all known Night Parrot times for ease of comparison and efficiency. vocalisations, including calls of nestlings and fledglings. We also present brief analysis of similarities between a call of the Night Parrot and a call of the Pallid Cuckoo Further notes on the Night Parrot’s hollow Heteroscenes pallidus. whistle

The single-note hollow whistle (Figure 1) is very similar to Study area and methods the Pallid Cuckoo’s ‘hoarse whistle’ (the latter described in Higgins 1999). Separating the calls has proven All vocalisations described in this paper were recorded problematic, especially as the Cuckoo occurs in similar from the Channel Country of western Queensland, the habitats (BRG pers. obs.) and often calls at night. The East Murchison district of central Western Australia, or the peak frequency (~2.1 kHz) and duration (~0.6 seconds) of Great Sandy Desert of northern Western Australia. the Cuckoo’s hoarse whistle closely match those of known hollow whistle recordings (BRG pers. obs.). However, Vocalisations were recorded on one of three different the Cuckoo call typically has a broader frequency range, models of autonomous recording unit (ARU): Songmeter giving the call a distinctively harsh or aggressive quality. SM2, SM3 or SM4 (Wildlife Acoustics Inc., Concord, This differs from the Night Parrot’s hollow whistle, which Massachusetts, USA). To obtain recordings of Night has a narrower frequency range, producing a thinner, more Parrot calls, ARUs were set to record from sunset until clean-sounding whistle. The Cuckoo call is usually slightly sunrise, under a variety of circumstances. Some were left sinuous in shape when viewed in a spectrogram, giving the in situ at known roosting sites for several years in order call a ‘wavy’ quality (Figure 3). This is often accentuated to understand site occupation, whereas others were by the presence of an inflection at the start and/or end of opportunistically placed for shorter periods at sites where the call. The strength of the call, and therefore distance Night Parrots had been detected roosting or breeding or of the bird from a sound recorder or observer influences were suspected to be drinking or feeding. the clarity of these features and, consequently, faint calls ARUs recorded sound files in .wav format, and these were in particular can be difficult to assign to Pallid Cuckoos or scanned for calls by manual listening, manually scanning Night Parrots with confidence. spectrograms, or using SongScope automated signal recognition software (Wildlife Acoustics Inc., Concord, Night Parrot nestling and fledgling Massachusetts, USA). Spectrograms were produced in vocalisations R (R Core Team 2018) using the package ‘seewave’ (Sueur et al. 2008). Examples of the calls described in this paper Rasp are posted on the Night Parrot website (www.nightparrot. This call has only been heard given by nestlings when com.au). Examples of all calls described for the first time a nest is approached by an observer. Sometimes the in this paper have been lodged with the Australian National nestlings remain silent when the nest is approached but, Wildlife Collection. if given, the call commences only when the observer is A secretive and cryptic nocturnal species, the Night Parrot within ~1 m of the nest. The call is a low, drawn-out rasp, is rarely observed vocalising. This presents a challenge similar to the begging call of a fledgling Rainbow Lorikeet when trying to identify the source of any suspected Trichoglossus moluccanus (Higgins 1999), but lower and call. Ethical considerations preclude the regular use of more drawn out. Each rasp lasts c. 3 seconds, and is techniques such as call-playback, spotlighting and daylight repeated continually until the observer departs. Vocalisations of the Night Parrot 81

Table 1. Summary of the key characteristics for all known ‘whistle’, ‘bell-like’ and ‘croak’ vocalisations (‘calls’ for brevity). Locations: CC = Channel Country, Queensland; EM = East Murchison, Western Australia; GSD = Great Sandy Desert, Western Australia. ANWC = Australian National Wildlife Collection references.

Call Description Duration (sec.) Peak Locations Comments ANWC frequency (kHz)

Whistles

Hollow whistle Loud, forceful whistle. 0.5–0.6 ~2.0 CC, EM, GSD Loud call that X49078 carries several Figures 1–2 Calls from EM have X49080 downwards ‘hook’ at hundred metres X49088 start. Calls from CC in still conditions. have sharp upwards Very similar to Pallid X49089 Cuckoo’s ‘hoarse hook at end. 2- and X49090 3-note variations known. whistle’ (Figure 3). Detections based X49091 solely on this call require additional evidence. One-note and May consist of 1 or 2 Each note: 0.3 ~2.2 CC, GSD Sequence of X49092 two-note trills ‘notes’, each of several shorter notes varies X49093 much shorter notes between CC and Figure 4 X49094 given as a rapid trill. GSD calls, but Sounds like a ringing overall sound is telephone. similar.

Two-note, three- Mellow whistle usually of Total duration of two- 2.1–3.0 CC. Similar Most calls at mid X49095 note and four- 2 notes: first note usually note whistle: 0.4 calls possibly to lower end of X49096 note whistles longer than second; detected from frequency range. Two-note whistle is X49097 Figure 5 notes usually of same EM. frequency, but second commonly heard at sometimes slightly CC sites. higher or lower than first.Three-note whistle is similar, but longer initial note is followed by 2 shorter notes, slightly higher than first note. Four-note whistle (previously described as dee-de-dee-de in Murphy et al. 2017a) consists of 2 consecutive two-note whistles. Toot Short, soft, low, single- 0.1 ~1.8 CC Known from only X49098 one CC site, and Figure 6 note whistle. recorded regularly there over past 2 years but, interestingly, not before despite intensive acoustic monitoring. Short whistle Short, sharp whistle. 0.2 ~2.1 EM Much less commonly X49099 heard than other Figure 6 When heard well, it has slight pulses calls at EM site. at beginning and end, apparent on a spectrogram. Peel Short, slightly upslurred 0.2 ~2.4 CC Apparently X49085 associated with Figure 7 whistle, similar to call of a small wader. breeding. Only known from one breeding attempt in 2016, and a possible breeding event in 2014. Peel, chirrup and prat were all given by the non- incubating bird as it visited the nest. 82 Australian Field Ornithology N.P. Leseberg et al.

Table 1 continued

Peak Call Description Duration (sec.) frequency Locations Comments ANWC (kHz) Whistles

Chirrup Mellow, slightly 0.3 ~3.6 CC Apparently X49081 associated with Figure 7 downslurred call, with a grating quality similar to breeding, and call of Masked Lapwing known from only one Vanellus miles. breeding attempt in 2016. Prat Very similar to 2-note 0.2 ~2.2 CC Rarely recorded. X49086 Possibly associated Figure 8 whistle of Australian Pratincole Stiltia isabella. with breeding. Occasionally, similar calls are heard, but not in circumstances definitely attributable to Night Parrot. Hook Short, low whistle, 0.2 ~2.0 EM Heard only once, X49100 amid a sequence of Figure 8 briefly upslurred at the beginning before hollow whistle and levelling out. croak calls. Bell-like calls Ding-de-ding 3-note call with a strong 0.4 First and CC Loud call that carries X49079 several hundred Figure 9 initial note, followed by last notes: 2 shorter notes, the first ~2.8; metres in still of higher frequency and middle conditions. Musical, the second of the same note: ~3.8 with chime- or flute- frequency as initial note. like quality. Dink-dink and 1 or 2 clear bell-like Total duration of 2.2–3.1, CC Commonly heard X49083 dink notes. Usually each note dink-dink call: 0.4 typically at all CC sites. Can X49101 be quite loud, but Figure 9 of dink-dink call is of ~2.5 the same frequency, but also given softly. second may be slightly Similar in quality to higher or lower. the bell-like call of Bell Miner Manorina melanophrys (Menkhorst et al. 2017). Didit Rapid 2-note call, Total duration of 2.2–3.1 EM, GSD Calls recorded from X49102 EM all ~2.2 kHz (and Figure 10 like beeping of small single didit call: 0.2 X49103 electronic equipment. probably all from Sometimes given same individual). multiple times in quick Calls from GSD all succession. 2.5–3.1 kHz. Croaks Croak Short, buzzy, relatively Duration of single Range: CC, EM, GSD Commonly heard X49082 when two birds Figure 11 high-pitched call, note: 0.1; sequence 1–10; X49087 very similar to the tjik of multiple calls may peak: are apparently in of Tawny Grassbird last several minutes. 3.5–4.0 close proximity, or Cincloramphus in response to other timoriensis (Menkhorst calls. Sometimes et al. 2017). Often given given when a bird is disturbed, either from several times in quick daytime roost, or in succession. Sometimes the open at night. a quieter, lower- frequency version.

Gruk Very soft, barely audible 0.1 ~1.0 EM Known only from one X49104 clucking call. instance in the EM. A bird landed very close to a recorder and gave a series of these very soft calls, among hollow whistle and croak calls. Vocalisations of the Night Parrot 83

Frequency (kHz) Frequency Time (s)

Time (s)

Figure 1. Comparison of hollow whistle calls from western Queensland and the East Murchison district of Western Australia. Frequency (kHz) Frequency

Time (s)

Figure 2. Two- and three-note variations of the hollow whistle call, from the East Murchison and Great Sandy Desert, respectively. The call to the right of the three-note variation (at 2.6 seconds) is of an Australian Owlet-nightjar Aegotheles cristatus. Frequency (kHz) Frequency

Time (s)

Figure 3. Comparison of two different Pallid Cuckoo ‘hoarse whistle’ calls from north-western Western Australia. The call on the left shows typical breadth of frequency, a sinuous shape, and hook at the end similar to hollow whistle calls from western Queensland. The call on the right is distant from the recorder, appearing narrower and more uniform in frequency, similar to a Night Parrot’s hollow whistle. 84 Australian Field Ornithology N.P. Leseberg et al. Frequency (kHz) Frequency

Time (s)

Figure 4. Comparison of two-note trill calls from Queensland and Western Australia. Sometimes a one-note version of the call is given. Each ‘note’ of the call actually consists of a sequence of much shorter notes, resulting in a trill-like sound. The shorter notes vary in length in the western Queensland call, but are all the same length in the Great Sandy Desert call. Frequency (kHz) Frequency

Time (s)

Figure 5. A typical two-note whistle call on the left, and a three-note whistle call on the right. The bird giving the call on the right was closer to the recording device, hence the bolder representation. Both calls are from western Queensland. Frequency (kHz) Frequency

Time (s)

Figure 6. A toot call from western Queensland on the left and short whistle call from the East Murchison on the right. Both are very simple calls. Vocalisations of the Night Parrot 85 Frequency (kHz) Frequency

Time (s)

Figure 7. A peel call on the left, and a chirrup call, with noticeable harmonics, on the right. Both calls are from western Queensland. Frequency (kHz) Frequency

Time (s) Figure 8. The prat call, only known from western Queensland, may be associated with breeding. The hook call has been detected only once, among a series of other calls recorded in the East Murchison. Frequency (kHz) Frequency

Time (s)

Figure 9. Dink-dink is a commonly heard call in western Queensland. Ding-de-ding is less commonly heard. 86 Australian Field Ornithology N.P. Leseberg et al. Frequency (kHz) Frequency

Time (s)

Figure 10. A single didit from the East Murchison on the left, and consecutive didits from the Great Sandy Desert on the right. Frequency (kHz) Frequency

Time (s)

Figure 11. A sequence of croak calls from western Queensland. Sequences like this may last for up to several minutes.

Whinny Discussion

Nestlings are silent or at least very quiet until they reach an The Night Parrot, like its closest relatives the Eastern age of c. 2–3 weeks. They then commence begging and, and Western Ground Parrots, has a varied repertoire of like many young parrots, beg repeatedly when an adult is vocalisations that is more diverse than for most parrots close to the nest or in the nest delivering food. The begging (Higgins 1999; Chan & Mudie 2004). For example, the call is a high-pitched whinny. Young birds also give this genera Neopsephotus and , which are the call during the period immediately after fledging. The two closest relatives of Pezoporus (Joseph et al. 2011; development of a begging call late in the nestling period Schweizer et al. 2013), have generally limited repertoires has also been noted in ground parrots Pezoporus spp. consisting mainly of simple calls that vary little, either (Courtney 1997). geographically or individually, across each species’ range (Higgins 1999). Each species in the genus Pezoporus has evolved cryptic plumage and a secretive natural history Wheet associated with dense low vegetation. This apparently restricts the usual opportunities for social interaction by Wheet is another begging call, detected at one site where visual means available to other parrots, an order known a pair of fledglings had apparently been out of the nest for the birds’ bright coloration and visually conspicuous for c. 10–14 days based on plumage development. The social behaviour (Forshaw 1989; Toft & Wright 2015). It fledglings could fly well, but remained in the nest area while is therefore perhaps unsurprising that Pezoporus parrots the adults presumably left to forage. Given repeatedly, the have evolved varied vocal repertoires, which provide call did not appear to be specifically in response to the the means for their intraspecific interactions, rather than proximity of the adults, although this is not certain. The call prominent visual displays. However, vocalisations in other is a high-pitched wheet, given continually. parrots are relatively poorly known, and these species’ Vocalisations of the Night Parrot 87

apparently varied repertoires may be the outcome of Night Parrots, should not be disturbed, and should be intense focus on vocalisations for this genus, given that reported to the relevant state authorities and to the Night this is the primary means of detection. Parrot Recovery Team. Although dialects exist within parrot species (Wright & Dahlin 2018), the amount of variation in Night Parrot Acknowledgements vocalisations at such a small scale, as well as at a larger We would like to acknowledge the Maiawali, Wiluna Martu and scale, seems unusual. Some calls, for example croak and Walmajarri/Wangkajungka people, on whose land the fieldwork hollow whistle, have been detected at each of the three for this paper occurred. Funding for fieldwork was provided by: sites and are apparently conserved across the species’ Bush Heritage Australia, Fortescue Metals Group, the Green range. Other calls, such as ding-de-ding, appear at this Fire Science research group at the University of Queensland, stage to be region specific, and some calls, such as toot, the Department of Biodiversity, Conservation and Attractions, are only known from a single site. The hollow whistle the National Environmental Science Program Threatened Species Recovery Hub, Birds Queensland, WWF-Australia, and one- and two-note trills had not been recorded in the Department of Prime Minister and Cabinet’s Working on the Channel Country before 2018, despite 5 years of Country and Indigenous Protected Areas Programs, and BirdLife intense research. Spatial and temporal variation in bird Australia. NPL received an Australian Government Research vocalisations may exist for several reasons, including Training Program scholarship, and additional funding through the social function, isolation or selection pressure, and similar Max Day Environmental Fellowship. Allan Burbidge, Penny Olsen fine-scale variation has been recorded in both Eastern and and Peter Menkhorst provided helpful comments on a draft. We Western Ground Parrots (Newbey & Burbidge 2002; Chan would like to acknowledge John Young who provided the catalyst & Mudie 2004). The reason for local variation in Night for this research by discovering the population of Night Parrots on Brighton Downs. Parrot calls is unclear and requires further study, although it is possibly an artefact of the small sample size currently available. References Burbidge, A.H., Rolfe, J., McNee, S., Newbey, B. & Williams, M. The significant variation in call types at a relatively small (2007). Monitoring population change in the cryptic and scale also suggests that some Night Parrot calls are still threatened in relation to fire. Emu 107, unknown. Given that call-detection is probably the most 79–88. suitable method for detecting and surveying Night Parrots, Chan, K. & Mudie, D. (2004). 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Observers should therefore be Press, Melbourne. cautious attributing hollow whistle calls to the Night Parrot. Hamilton, N., Burbidge, A.H., Douglas, T.K. & Gilbert, L. (2017). Although the traits outlined here are a guide to the possible Piecing the puzzle together: The fate of the Night Parrot nest species, even some strong hollow whistle calls cannot be found in Western Australia by Jackett et al. (2017). Australian definitely attributed to either species. A lack of reference Field Ornithology 34, 151–154. calls for both species is inhibiting work on separating these Higgins, P.J. (Ed.) (1999). Handbook of Australian, New Zealand two calls. Records of the Night Parrot based solely on the & Antarctic birds, Volume 4: Parrots to Dollarbird. Oxford University Press, Melbourne. detection of this call should thus be treated as unconfirmed Ison, S. (2017). Night parrot recording a coup for club. Bussleton until corroborated through the detection of other known Dunsborough Times 27 October 2017. Available online: https:// calls or additional evidence. thewest.com.au/news/regional/night-parrot-recording-a-coup- for-club-ng-b88641203z (retrieved 7 March 2018). This research underlines the requirement to investigate Jackett, N.A., Greatwich, B.R., Swann, G. & Boyle, A. (2017). A vocalisations that may not precisely match the descriptions nesting record and vocalisations of the Night Parrot Pezoporus here, particularly if the context suggests that the call occidentalis from the East Murchison, Western Australia. may be a Night Parrot. Flushing birds during the day Australian Field Ornithology 34, 144–150. should always be avoided, but confirmation can still be Joseph, L., Toon, A., Schirtzinger, E. & Wright, T. (2011). Molecular achieved with minimal disturbance through observations systematics of two enigmatic genera Psittacella and Pezoporus in and around the Parrot’s roosting sites close to dusk, illuminate the ecological radiation of Australo-Papuan parrots. when they are known to become active, or the judicious Molecular Phylogenetics and Evolution 59, 675–684. Koch, T. (2013). Is this a sighting of Australia’s most elusive bird, use of call-playback. The discovery of the species in the the night parrot? The Australian 29 June 2013, p. 1. Available East Murchison of Western Australia demonstrated the online: https://www.theaustralian.com.au/news/health-science/ importance of ethically confirming the identification of tweets-in-the-night-a-flash-of-green-is-this-our-most-elusive- possible Night Parrot calls. As a direct result of visually bird/news-story/520172e73df7da9e7195d9bf569f9538 confirming that the unusual calls heard at the East (retrieved 15 August 2016). Murchison site were in fact Night Parrots, this additional Mallee Bird [C. McLennan] (1908). A trip to Sunset. The site where the species occurs in Western Australia was Australasian 4 April 1908, p. 52. detected. However, it must be stressed that the purpose McDougall, A., Porter, G., Mostert, M., Cupitt, R., Cupitt, S., Joseph, L., Murphy, S., Janetzki, H., Gallagher, A. & Burbidge, A. of any disturbance without the necessary research permits (2009). Another piece in an Australian ornithological puzzle – a should be limited to identifying birds making unknown second Night Parrot is found dead in Queensland. Emu 109, calls. Birds giving calls described herein are likely to be 198–203. 88 Australian Field Ornithology N.P. Leseberg et al.

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