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Australian Field Ornithology 2020, 37, 67–75 http://dx.doi.org/10.20938/afo37067075

Incubation behaviour and uniparental nestling care in the Huon Astrapia rothschildi (Paradisaeidae)

Richard H. Donaghey1, 2*, Donna J. Belder3 and Tony Baylis4

1Environmental Futures Research Institute, Griffith University, Nathan QLD 4111, Australia 280 Sawards Road, Myalla TAS 7325, Australia 3Fenner School of Environment and Society, The Australian National University, Canberra ACT 2601, Australia 4628 Utopia Road, Brooweena QLD 4621, Australia *Corresponding author. Email: [email protected]

Abstract. The Huon Astrapia Astrapia rothschildi is endemic to the mountains of the Huon Peninsula, Papua . We document, for the first time, the nest-site and height above the ground, incubation behaviour, nestling period, and uniparental care of the nestling (including brooding, feeding rate, nestling meals and nest hygiene) of the Huon Astrapia in the Yopno Urawa Som Conservation Area. Only the female incubated the single-egg clutch and provisioned the nestling. Incubation constancy was 67%. The nestling period was 25–27 days. Time spent brooding during the first week of the nestling period averaged 59%. The female provisioned the nestling at an average rate of 2.3 meals per hour. Of 32 nestling meals that could be identified, 81% were , predominantly insects, and 19% were fruit. Nearly all meals were regurgitated, and the female consumed most faecal sacs. We present four spectrograms: vocalisations of two females attending a nestling in their nests, and nestling calls. We compare incubation behaviour and uniparental nestling care of the Huon Astrapia with those in other -of-paradise, especially within the Astrapia clade.

Introduction to mainland New Guinea, are sexually dimorphic in size and plumage: adult males are ~10% larger than females, The 41–43 of birds-of-paradise (Paradisaeidae) and are predominantly black with an iridescent greenish- (Beehler & Pratt 2016; Gill & Donsker 2019) are renowned blue head; females are dull blackish brown with barred for their exquisite beauty and plumage, and their diversity underparts. of extraordinary courtship displays (Gilliard 1969; Cooper The Huon Astrapia Astrapia rothschildi is confined to & Forshaw 1977; Coates 1990; Frith & Frith 2009; Laman montane rainforest in the Finisterre, Saruwaged, Rawlinson, & Scholes 2012; Ligon et al. 2018). Males of the majority and Cromwell Mountains of the Huon Peninsula from of birds-of-paradise (35–37 species) are presumed to 1460–3500 m above sea level (asl) (Beehler & Pratt 2016); be promiscuous and polygynous, with females providing here it is the only species of Astrapia present. It forages for sole parental care (Frith & Beehler 1998; Frith & Frith and fruits in the middle-to-upper storeys of the 2009). By contrast, the four Manucodia species, the forest. Solitary displaying, dispersed males have a unique Trumpet Phonygammus keraudrenii, and the inverted courtship display (Frith & Beehler 1998; Laman & Paradise-crow Lycocorax pyrrhopterus are considered to Scholes 2012; Scholes et al. 2017). Thane Pratt (in Frith be monogamous with biparental care of offspring (Beehler & Beehler 1998) described an inverted courtship display in 1985; Frith & Beehler 1998; Frith & Frith 2009). The diets which a male slides below a horizontal perch, points his bill of adults and nestlings are important factors promoting the evolution of social systems such as mating system, male skywards and cocks his long fanned tail upward. Laman spatial dispersion and parental care in birds-of-paradise & Scholes (2012) described a courtship display in which (Beehler 1983; Beehler & Pruett-Jones 1983; Diamond the male hangs upside down, resumes an upright posture 1986; Frith & Beehler 1998). Male territorial dispersion for copulation and after copulation grasps the back of the in the presumed polygynous female, leans forward, and both male and female tumble meyeri correlated with a more insectivorous diet but a far down locked together. greater frugivorous diet favoured the evolution of true leks Very little is known about the breeding biology of the Huon in the Raggiana -of-Paradise raggiana Astrapia. Two nests and an egg have been described (Frith (Beehler 1983; Beehler & Pruett-Jones 1983). In contrast, 1971; Frith & Beehler 1998) but neither the nest-site nor in a study at Mt Missim, the specialised height of nest above the ground is known. The incubation in eating nutrient-poor, spatially and temporally patchy, and nestling periods, incubation behaviour, and parental rare figs (Moraceae), which promoted biparental care of care of the young are unknown. In this paper, we describe young, monogamy, and non-territorial dispersion (Beehler the nest-site and nest height, and document female 1985; Diamond 1986). incubation behaviour and parental care of the single young The phylogeny of birds-of-paradise by Irestedt et (including feeding rates, nestling diet, and nest sanitation) al. (2009) recognised five main clades, four of which at a nest in the Yopno Urawa Som Conservation Area represented the core birds-of-paradise. The five Astrapia (YUS CA), Huon Peninsula, Papua New Guinea (PNG). species are included in the fourth clade together with the We present spectrograms of vocalisations of the female two species and the two long-tailed Epimachus and nestling Huon Astrapia, and present photographs of sicklebills. The long-tailed Astrapia species, all endemic the nest-site, nest, and an adult female feeding a nestling. 68 Australian Field Ornithology R.H. Donaghey et al.

Study site and methods At Nest 1 on 13 November, TB recorded the calls of a female that visited her nest and the calls of the nestling RHD and David Bryden conducted a 6-week exploratory using a DPA4060 omnidirectional microphone (placed trip that included the Huon Peninsula, during July– below the nest) with a long lead run to a Nagra LB August 2014, and selected the YUS CA as a study site recorder, with file type WAV 48 kHz/24bit during a session (Donaghey 2015a). Soon after, we flew into Sapmanga, lasting c. 86 minutes. He recorded the calls of a female YUS CA, elevation 900 m asl, arranged porters and guides returning to Nest 2 using a Sennheiser ME62 Cardiode at Gomdan village and walked up to Camp 12, elevation microphone (placed above the nest) with a short lead into 2300 m asl (06°01′S, 146°50′E), where we studied mid- an Olympus LS11 recorder, file type WAV 48 kHz/24bit. This mountain robins (Petroicidae) and opportunistically studied recorder was run for 65, 86 and 70 minutes on 9, 13 and other songbird species from 23 October to 6 December 20 November, respectively. Spectrograms were produced 2014 (Donaghey et al. 2019). While walking along a using Raven Pro 1.4 with FFT1024. trail uphill from Camp 12 on 25 October, we discovered Nest 1 of a Huon Astrapia when the incubating female flew The vegetation structure and plant families in a 1-ha from her nest. To determine her incubation behaviour, we plot of mid-montane rainforest 2400 m asl near Camp 12 erected a portable hide before 1200 h on 26 October, and were described by Inaho (2012). This upper-zone forest then RHD and DJB alternated 2-h nest-watches spanning plot was characterised by high stem density (mean of all daylight hours from 1200 h to 1800 h on 26 October and 25 stems/0.4 ha) and a tree height of mostly 10–20 m from 0600 h to 1200 h the following morning. dominated by one species (Platea excelsa) in the family We observed the female Huon Astrapia at the nest Icacinaceae. The other most important plant families are through a 25× telescope and timed the duration of all listed in Inaho (2012) and Donaghey et al. (2019). In this bouts on and off the nest to the nearest second with a plot, Inaho (2012) recorded 39 plant species in 36 genera lap/split stop-watch. An incubation session or ‘on-bout’ is and 28 families. During our stay at Camp 12 in October– the duration of time (minutes and seconds) spent by the December 2014, there was little sunshine, and heavy rain female on the nest during incubation. An absence or ‘off- fell most afternoons, evenings, and some mornings. bout’ is the time (minutes and seconds) that an incubating female spent away from the nest. In our study, incubation constancy is the percentage of a 12-hour day spent in Results incubation. In other studies of birds-of-paradise (discussed below), incubation constancy refers to the mean percentage Nest-site, nest, and nest dispersion of time that the female spent incubating during several nest-watches. While walking past the nest-site between Nest 1 (Figures 1–2), placed 5 m above the ground, was 27 October and 4 November, we opportunistically recorded whether the female was on the nest or foraging nearby. well-concealed in a tangle of epiphytic Freycinetia, a of mostly climbing plants (Pandanaceae), against the During a 1-hour afternoon nest-watch on 5 November, trunk (9 cm at breast height) of a slender understorey tree we observed the female visit the nest and deliver food, (9–10 m tall). The nest-tree was on a west-facing slope presumably to an unseen nestling. We assumed that at an altitude of 2470 m asl, and the nest had a southerly 5 November was Day 1 of the nestling period since on aspect. Nest 1, a substantial open cup of orchid stems, the afternoon of 4 November we saw the female return vines and rootlets, externally measured 215 mm in to her nest with no food in her bill. During the first week diameter and had a mean depth of 150 mm. We were of the nestling period, we observed Nest 1 on 5, 7 and unable to examine the interior nest materials or measure 11 November for a total of 9.5 hours. We recorded the width and depth of the interior cup. Nest 2 was placed presence or absence of the female at Nest 1 from 12 to 2.5 m above the ground in the crown of a tree-fern Cyathea 24 November, but did not conduct any nest-watches. From Days 20–25 of the nestling period, we watched Nest 1 on sp. growing beside a stream below Camp 12, at an altitude 25, 27, 28 and 30 November for a total of 9.5 hours. During of 2200 m asl (Figures 3–4). The ground distance between the nestling period, we recorded the time that the female Nests 1 and 2 was 718 m. spent brooding, the number of feeding trips per hour, the food items fed to the young, nest-sanitation behaviour, and comfort movements of the young. The percentage of Incubation behaviour time spent by the female on the nest brooding the young was determined from 9.5 hours of observation on 3 days Only the female incubated the single egg-clutch at in the first week of the nestling period. After the young had Nest 1. Incubation constancy during a 12-hour nest- fledged, we measured the characteristics of the nest-site watch from 1200 h to 1800 h on 26 October and and height of the nest above the ground. 0600 h to 1200 h the next morning was 67% and averaged Nest 2, found on 31 October by Keshdy Awa, contained 63.1% for the first 4 hours, 64.4% for the next 4 hours and a small chick that fledged on 20 November. Assuming that 73.6% for the last 4 hours of daylight. Hourly incubation the nestling period is 26 days, we estimated the age of constancy ranged from 41.5% to 96.3% (Table 1). The this nestling by backdating from the day of fledging. At mean length of incubation sessions was 24.8 minutes ± Nest 2, no nest-watches were conducted, but vocalisations standard deviation 11.3 minutes (range 6–51.68 min., of the attending female and her nestling were recorded n = 19), and for absences was 11.3 ± 5.63 minutes (range (see below). The distance between Nests 1 and 2 was 2.23–23.98 min., n = 21). The number of complete determined from their latitude/longitude co-ordinates incubation sessions plus one partial session over a obtained by GPS. 12-hour day was 19. Huon Astrapia incubation and nestling care 69

Figure 1. Nest-tree of Huon Astrapia Nest 1 and surrounding Figure 3. Stream-side rainforest at the tree-fern site of mid-montane rainforest in the YUS CA, Huon Peninsula, Huon Astrapia Nest 2, below Camp 12, YUS CA, PNG. The PNG. The arrow points to the nest. Photo: Donna J. Belder arrow points to the nest-tree fern. Photo: Tony Baylis

Figure 2. Site, structure and external materials of Nest 1 Figure 4. Site of Nest 2 in crown of tree-fern. The arrow concealed by epiphytic Freycinetia. Photo: Richard H. points to the nest. Photo: Tony Baylis Donaghey

Nestling period and parental care of nestling 1030 h on 2 December or the previous day, the nestling period was 25–27 days. We observed the female Huon Astrapia deliver food Watches at Nest 1 totalling 19 hours (9.5 h each during to a nestling in Nest 1 at 1628 h on 5 November. She the first and last week of the nestling period) confirmed then uttered clucking notes and settled on the nest, and presumably brooded the young, for 36.03 minutes. We last that only the female visited the nest and she provided all observed the young in the nest at 0900 h on 30 November. parental care. During the first week of the nestling period, Nest 1 was not monitored on 1 December, but when the percentage of time that the female spent brooding checked on 2 December at 1030 h, neither young nor the young averaged 59.2% and ranged from 76.3% adult was seen. Assuming that the nestling fledged before (Day 1) to 60.9% (Day 7) (Table 2). Length of brooding 70 Australian Field Ornithology R.H. Donaghey et al.

Table 1. Nest-attentiveness of a female Huon Astrapia during the incubation period (Nest 1), YUS CA, PNG, 2014. Date is given as day.month.

Date Time (h) Minutes Incubation constancy On nest Off nest (%) 26.10 1200–1300 44.53 15.47 74.2 1300–1400 36.96 23.04 61.6 1400–1500 24.92 35.08 41.5 1500–1600 47.53 12.47 79.2 1600–1700 46.30 13.70 77.2 1700–1800 57.77 2.23 96.3 27.10 0600–0700 33.62 26.38 56.0 0700–0800 43.39 16.61 72.3 0800–0900 46.45 13.55 77.4 0900–1000 27.93 32.07 46.6 1000–1100 46.90 13.10 78.2 1100–1200 26.17 33.83 43.6 12-h totals 482.47 237.53 12-h mean 67.0

Figure 5. Adult female Huon Astrapia feeding her single nestling. Photo: Donna J. Belder bouts averaged 17.4 minutes (range 5.57–53.12 min., (range 2.0–69.0 min., n = 41). During the first week of n = 17). From Days 8 to 19, we checked Nest 1 eight the nestling period, nine of 15 identified meals were all times, but brooding was observed only twice: at regurgitated, and arthropods were carried in the bill six 1215 h on Day 8 and at 1750 h on Day 19. No brooding was times. In the last week, all 19 meals were regurgitated. observed during nest-watches on Days 20–25. Excluding one feeding/brooding visit on Day 1, the overall mean time that the female spent at the nest feeding the nestling and Nestling meals and nest-sanitation behaviour in nest hygiene was 1.27 minutes (range 0.33–5.87 min., n = 36) (Table 2, Figure 5). The rate of food-delivery trips Of 18 meals delivered to the nestling in the first week of to the nest ranged from 1 feed/hour on Day 1, through the nestling period, 15 were exclusively insects, and three 1.5 feeds/hour (Day 3) and 2.5 feeds/hour (Day 7) to were unidentified. In the last week, 11 of 17 identified 4 feeds/hour on Days 20 and 23 (Table 2). On Day 25, meals (64.7%) were animal (predominantly insects) and 1–2 days before fledging, the feeding rate was reduced six (35.3%) were fruit. One meal consisted of a skink to 1.2 feeds/hour and the mean length of absences (Scincidae) carried in the bill followed by four regurgitations increased to 36.5 minutes. The mean length of absences of insects. Another meal comprised an earthworm from the nest for each nest-watch is shown in Table 2. (Annelida) carried in the bill followed by five regurgitations The overall mean absence length was 18.42 minutes of insects. Overall, of 32 identified meals, 81.2% were Huon Astrapia incubation and nestling care 71

1 2 2 5 U animal (predominantly insects) and 18.8% were fruit. Arthropods identified included a spider (Arachnida), adult

3 1 2 6 F beetles (Coleoptera) and larvae, and winged insects such meals as flies (Diptera) and wasps (Hymenoptera).

7 8 3 3 2 3 A 26 No. nestling During the first week of the nestling period, ingestion of

) ) faecal sacs was not visible. During the last week, between 25 and 30 November, we observed the female deliver 5.87)

– 19 meals to the nestling. On 18 of these feeding trips, the nestling ejected a faecal sac. The female consumed 15 of these sacs at the nest, and flew off with a sac on

Mean length, three occasions. After she consumed a sac at the nest, 1.00 (0.68–1.27) 0.72 (0.33–1.02) 2.07 (0.70–5.87) 1.13 (1.00–1.22 1.65 (0.73–2.87 1.34 (0.97–1.82) 1.27 (0.33 min. sec. (& range) she repeatedly probed the nest-cup with her bill, vigorously shook the nest, and retrieved and ate small pieces of food

Feeding trips and faecal matter. 1.0 1.5 2.5 4.0 2.0 4.0 1.2 2.3 No./h 1 7 8 4 4 3

10 37 Vocalisations by female and nestling Total no. Total The spectrogram in Figure 6, recorded at 1150 h on

) 13 November, depicts the calls of a female at Nest 1 with ) ) her 8-day-old nestling. After brooding the nestling for

69.0) c. 30 minutes, she left the nest but returned after – c. 50 minutes and gave quiet short calls with a frequency range of 800–2000 Hz. The calls were given intermittently

Mean length, for most of the time while she attended the nest for 7.03 (5.53–8.52) 9.65 (2.0–22.23 24.83 (4.0–47.0 18.42 (2.0 min. sec. (& range) 16.55 (2.87–28.42) 10.68 (8.85–15.20 36.50 (9.73–69.00) c. 7 minutes. 23.10 (18.12–27.62) The spectrogram in Figure 7, recorded at 0713 h on Absences from nest 20 November, shows vocalisations of a female returning to 2 7 9 9 5 5 4 41 No. Nest 2 shortly after the nestling had fledged in her absence. These vocalisations were similar to those in Figure 6 but slightly louder and higher in pitch. The vocalisations began c.15 seconds after she arrived at the nest and continued 14.0 86.84 53.38 118.70 115.50

223.45 145.98 for c. 30 seconds, after which she departed from the nest. Off nest The spectrogram in Figure 8, recorded at 1205 h on 13 November, depicts quiet repetitive begging calls (~2700 Hz) given by an 8-day-old nestling in Nest 1. Calling

44.6 from the chick became more persistent c. 7 minutes after Feeding 6.02 (2.2) 6.89 (2.9) 4.02 (2.7) young (%) 6.62 (11.0) 16.55 (6.9) 4.50 (3.75) the female’s arrival. The spectrogram in Figure 9, recorded at 1020 h on 9 November at Nest 2, shows vocalisations from the female and her nestling that are similar in their sound quality to those in Figures 6–8. The nestling (estimated to be 59.2% 337.35 c. 15 days old) uttered begging calls a few seconds after 45.8 (76.3) Brooding (%) 145.28 (53.8) 146.27 (60.9) the female arrived at the nest. The calls of this nestling were similar to those given by the nestling in Nest 1 Time (min.) female spent on and off nest Time (Figure 8). 46.0 4.50 6.62 4.02 16.55

151.30 153.16 At both Nests 1 and 2, vocalisations from nestlings were On nest heard only in the presence of the female. 60 60 270 240 240 120 150 Obs. 1140 Discussion

Breeding season, nest, egg and clutch-size

The nesting season (i.e. egg in nest being only known data) Time (h) Time 1100–1300 1100–1300 1000–1100 1620–1720 1330–1800 1415–1815 1400–1800 0630–0900 of the Huon Astrapia occurs in October–November (Frith & Beehler 1998). In our study, the breeding season extended from mid–late September to the end of November. 5.11 7.11 Date 11.11 25.11 27.11 28.11 30.11

Uniparental care of a nestling by a female Huon Astrapia at Nest 1, YUS CA, PNG, 2014. Day = day of nestling period; date = day.month; obs. = length of observation period obs. = length of observation = day.month; period; date of nestling = day Day 1, YUS CA, PNG, 2014. Nest at Huon Astrapia a female by of a nestling care Uniparental The external diameter and depth of Huon Astrapia Nest 1 (this study) was the same as for the largest recorded Ribbon-tailed Astrapia nest (Frith & Frith 1993; Frith & Day 1 3 7 20 22 23 25 Total Mean

Table 2. Table hygiene; young includes nest feeding and in parentheses, shown young are feeding and for brooding of time percentages on and off nest: female spent by time (minutes) (minutes); meals: A = animal, F fruit, U unidentified. number of nestling in parentheses; with range and seconds, in minutes shown are absences Beehler 1998) but was much larger than for two other Huon 72 Australian Field Ornithology R.H. Donaghey et al.

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5 Frequency (kHz) Frequency

1 2 3 Figure 6. Spectrogram of the vocalisations Secondsof an adult female Huon Astrapia at her nest (Nest 1) with an 8-day old nestling. Spectrogram: Tony Baylis Figure 6. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) with an 8-day-old nestling. Spectrogram: Tony Baylis

Figure 6. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) with an 8-day old nestling. Spectrogram: Tony Baylis

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10 FigureFigure 6.7. SpectrogramSpectrogram ofof thethe vocalisationsvocalisations ofof anan adultadult femalefemale HuonHuon AstrapiaAstrapia atat herher nestnest (Nest 2)1) shortlywith an after 8-day oldher nestling.nestling Spefledged.ctrogram: Spectrogram: Tony Baylis Tony Baylis 5 Frequency (kHz) Frequency

1 2 3 4 5 6 7 Figure 7. Spectrogram of the vocalisations of an adult female Huon Astrapia at Secondsher nest (Nest 2) shortly after her nestling fledged. Spectrogram: Tony Baylis Figure 6. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) with an 8-day old nestling. Spectrogram: Tony Baylis Figure 7. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 2) shortly after the nestling fledged. Spectrogram: Tony Baylis

Figure 8. Spectrogram of the vocalisations of an 8-day old nestling Huon Astrapia in Nest 1. Spectrogram: Tony Baylis Figure 7. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 2) shortly after her nestling fledged. Spectrogram: Tony Baylis

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Figure10 8. Spectrogram of the vocalisations of an 8-day old nestling Huon Astrapia in Nest 1. Spectrogram: Tony Baylis

Figure 7. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 2) shortly after her nestling fledged. Spectrogram: Tony Baylis 5 Frequency (kHz) Frequency

2 3 4 5 6 Figure 8.9. Spectrogram of the vocalisations of an 8-adultday oldfemale nestling Huon Huon AstrapiaSeconds Astrapia at her in Nestnest (Nest1. Spectrogram: 1) and those Tony of herBaylis 8-day old nestling. Spectrogram: Tony Baylis Figure 8. Spectrogram of the vocalisations of an 8-day-old nestling Huon Astrapia in Nest 1. Spectrogram: Tony Baylis

Figure 9. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) and those of her 8-day old nestling. Spectrogram: Tony Baylis Figure 8. Spectrogram of the vocalisations of an 8-day old nestling Huon Astrapia in Nest 1. Spectrogram: Tony Baylis

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10 Figure 9. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) and those of her 8-day old nestling. Spectrogram: Tony Baylis

5 Frequency (kHz) Frequency

1 2 3 4 5 Figure 9. Spectrogram of the vocalisations of an adult female HuonSeconds Astrapia at her nest (Nest 1) and those of her 8-day old nestling. Spectrogram: Tony Baylis

Figure 9. Spectrogram of the vocalisations of an adult female Huon Astrapia at her nest (Nest 1) and those of her 8-day-old nestling. Spectrogram: Tony Baylis Huon Astrapia incubation and nestling care 73

Astrapia nests (Frith 1971; Frith & Beehler 1998). Huon reflect a higher risk of nest-depredation in upland north- Astrapia nests are mostly constructed externally of orchid eastern Australia than in montane PNG. Conway & Martin stems, vines and rootlets with some green-leaved orchid (2000) and Donaghey et al. (2019) found that for many stems (this study; Frith & Beehler 1998). Frith & Beehler northern-temperate songbirds, and for the Satin Bowerbird (1998) also reported that some Huon Astrapia nests are Ptilonorhynchus violaceus (Ptilonorhynchidae), a high built of stems of a Bulbophyllum orchid. By comparison, the risk of nest-depredation appears to have favoured a high nest of the Ribbon-tailed Astrapia is “sparsely to densely incubation constancy and relatively long incubation on- covered by fresh, green-leaved, epiphytic orchid stems” bouts. (Frith & Beehler 1998, p. 263). Nest 2 of the Huon Astrapia was built in the crown of a tree-fern (this study), and Nest 9 Nestling period, nestling parental care and of the Ribbon-tailed Astrapia studied intensively by Frith & Frith (1993) was also in the crown of a tree-fern. Within the nestling diet Astrapia clade, no sticks are incorporated in nests of the Huon Astrapia (this study; Frith & Beehler 1998), Ribbon- The nestling period of the Huon Astrapia was tailed Astrapia and Short-tailed Paradigalla Paradigalla 25–27 days (this study), nearly identical to 26 days in both brevicauda (Frith & Beehler 1998) or any other birds-of- the Ribbon-tailed Astrapia (Frith & Frith 1993) and Short- paradise, excluding the Satinbirds (Cnemophilidae). tailed Paradigalla (Frith & Frith 1992), two closely related and similar-sized species. The clutch-size of one egg in the montane Huon Astrapia (this study; Frith & Beehler 1998) conforms with those of In the first week of the nestling period, the mean time 21 other species of montane birds-of-paradise in mainland that a female Huon Astrapia spent brooding was 59.2% New Guinea (Frith & Beehler 1998; Frith & Frith 2009; (this study), compared with 39.3% in the Ribbon-tailed Donaghey 2015b). Astrapia (Frith & Frith 1993) and 21% (range 32–55%) in Victoria’s Riflebird (Frith & Frith 1995). The mean length of brooding bouts was 17.4 minutes in the Huon Astrapia Incubation (this study), compared with 12.7 minutes (range 4.6– 34.35 min.) in the Short-tailed Paradigalla (Frith & Frith On the whole, incubation constancy of the Huon Astrapia 1992) and 6.5 minutes (range 5.38–8.02 min.) in the King resembles that of other birds-of-paradise with only female of Saxony Bird-of-Paradise (Frith & Frith 1990). The mean attendance at the nest. For the nine species of birds-of- number of food-delivery trips to the nest by the Huon Astrapia paradise with female uniparental care within the Astrapia was 2.3/hour and the mean length of these nest visits was clade, the female Huon Astrapia spent 67% of daylight 1.27 minutes (range 0.33–5.87 min., n = 37: Table 2) hours incubating (this study) compared with 66% (range compared with 5.1/hour and 2.1/hour (range 0.7–2.5/h), 61–84%) in the Ribbon-tailed Astrapia (Frith & Frith 1993) respectively, in the Ribbon-tailed Astrapia (Frith & Frith and 58.2% (range 44–86%) in the Short-tailed Paradigalla 1993) and Short-tailed Paradigalla (Frith & Frith 1992). (Frith & Frith 1992). There are no comparable data on The overall mean length of absences that the female incubation constancy for the other three Astrapia species, Huon Astrapia spent away from Nest 1 with a nestling was the Long-tailed Paradigalla Paradigalla carunculata, and 18.42 minutes (range 2.0–69.0 min., n = 41) compared the two species of Epimachus sicklebills. Furthermore, with 8.75 minutes in the Ribbon-tailed Astrapia (Frith & there are very few data for the core birds-of-paradise in the Frith 1993) and 18 minutes (range 9.70–29.53 min.) in the second, third and fifth clades. The fifth clade, closely related Short-tailed Paradigalla (Frith & Frith 1992). The higher to , includes the six lek-displaying Paradisaea mean feeding rate and shorter mean absence length in the species, the Blue Bird-of-Paradise P. rudolphi, two species Ribbon-tailed Astrapia probably reflect the much higher of Diphyllodes, and the King Bird-of-Paradise proportion of low-protein fruit in the diet of nestlings of that regius (Irestedt et al. 2009). For the 9 days before hatching species, and a shorter time spent gathering fruit, compared of the egg, a female Raggiana Bird-of-Paradise spent with the high-protein insectivorous nestling diet in the Huon ~75% of the time incubating (Davis & Beehler 1994), and Astrapia (this study) and Short-tailed Paradigalla (Frith & incubation constancy was 64% in the Blue Bird-of-Paradise Frith 1992). (Mack 1992). In the second and third clades, respectively, incubation constancy is 58.3% in the King of Saxony Bird- of-Paradise Pteridophera alberti (Frith & Frith 1990) and Diet of nestlings 71% (range 62–86%) in Victoria’s RiflebirdPtiloris victoriae (Frith & Frith 1995). Within the Astrapia clade, the diet of a single Huon Astrapia Length of incubation sessions varies widely in nestling in Nest 1was 81.2% animal and 18.8% fruit (this birds-of-paradise, though perhaps larger sample study), and of 66 identified nestling meals in the Short- sizes would be needed to support this generalisation tailed Paradigalla, 65% were animal, 30% fruit, and 5% statistically. The mean length of incubation sessions was both animal and fruit (Frith & Frith 1992). In contrast, of 24.8 minutes in the Huon Astrapia (this study), compared with 147 identified nestling meals in the Ribbon-tailed Astrapia, 16.30 minutes in the Ribbon-tailed Astrapia (Frith & Frith 63% were fruit, 31% animal and 6% both fruit and animal 1993), 17.08 minutes in the Short-tailed Paradigalla (Frith (Frith & Frith 1993). In Victoria’s Riflebird, the nestling & Frith 1992), 8.62 minutes in the King of Saxony Bird-of- diet was predominantly animal, mostly insects (Frith & Paradise (Frith & Frith 1990) and 44 minutes in Victoria’s Frith 1995). Dietary differences in the proportion of animal Riflebird (Frith & Frith 1995). The longer incubation sessions, and fruit in montane New Guinea birds-of-paradise are higher incubation constancy, and shorter nestling period not well understood but presumably reflect seasonal and (17–19 days) in Victoria’s Riflebird (Frith & Frith 1995) may geographical differences in food availability, the spatial 74 Australian Field Ornithology R.H. Donaghey et al.

and temporal dispersion of food resources, and perhaps forests at Tari Gap, Southern Highlands, PNG. We thank Cliff bill morphology. Frith and Thane Pratt for constructive reviews and Cliff Frith and Julia Hurley for their thorough editing. We dedicate this paper to Mary LeCroy for her love of birds-of-paradise and her decades Nest-sanitation behaviour of commitment and dedication to the birds of New Guinea, at the American Museum of Natural History. Nest-sanitation behaviour is parental behaviour that cleans the nest by removing objects such as eggshells, faeces, References uneaten food and ectoparasites (Guigueno & Sealy 2012). Beehler, B. (1983). Frugivory and polygamy in birds of paradise. In the present study, the uniparental female Huon Astrapia Auk 100, 1–12. swallowed most faecal sacs at the nest, and consumed Beehler, B. (1985). Adaptive significance of monogamy in pieces of faeces and particles of uneaten food retrieved the Trumpet Manucode Manucodia keraudrenii (Aves: from the bottom of the egg-cup. The ingestion of faecal Paradisaeidae). In: Gowaty, P.A. & Mock, D.W. (Eds). Avian sacs has been recorded in all studies on the nesting biology Monogamy. Ornithological Monographs No. 37, pp. 83–99. The of birds-of-paradise (Frith & Beehler 1998 and references American Ornithologists Union, Washington DC, USA. Beehler, B. & Pruett-Jones, S.G. (1983). Display dispersion therein). Parental probing and shaking of the nest with and diet of birds of paradise: A comparison of nine species. the bill may improve nest aeration, keep the nest drier Behavioral Ecology and Sociobiology 13, 229–238. or dislodge and reduce ectoparasites, but in the present Beehler, B.M. & Pratt, T.K. (2016). Birds of New Guinea: study the nest was not examined for any ectoparasites. Distribution, , and Systematics. Princeton University Press, Princeton, New Jersey, USA. Coates, B.J. (1990). The Birds of Papua New Guinea, Volume I: Vocalisations of the female and nestling . Dove Publications, Brisbane. Conway, C.J. & Martin, T.E. (2000). Evolution of incubation behavior: Influence of food, temperature, and nest Pratt & Beehler (2015) stated that the Huon Astrapia predation. Evolution 54, 670–685. is mainly quiet. The vocalisations described by Pratt Cooper, W.T. & Forshaw, J.M. (1977). The Birds of Paradise and & Beehler (2015, p. 482) include a ‘kak kak kak kak’, a Bower Birds. Collins, Sydney. typical Astrapia ‘wenh?’ note and a low growl. The sex Davis, W.E., Jr, & Beehler, B.M. (1994). Nesting behaviour of a of the bird giving these calls was not recorded by Pratt Raggiana Bird of Paradise. Wilson Bulletin 106, 522–530. & Beehler (2015). Thane Pratt in Frith & Beehler (1998) Diamond, J. (1986). Biology of birds of paradise and bowerbirds. described adult males making loud, sharp, dry, hissing, Annual Review of Ecology and Systematics 17, 17–37. rattle sounds in flight. Laman & Scholes (2012, p. 213) Donaghey, R. (2015a). Adventures in New Guinea. A dream described the vocalisation as “Little known; a throaty fulfilled? The Natural News 61, 2–10. froglike croak repeated two or three times is given from Donaghey, R.H. (2015b). Nest and egg of the Dimorphic display perches”. The Huon Astrapia has a restricted Rhipidura brachyrhyncha and a review of clutch-sizes in New Guinean passerines. Australian Field Ornithology 32, 69–86. geographical range that is difficult to access, and thus it Donaghey, R.H., Belder, D.J., Baylis, T. & Gould, S. (2019). is no surprise that vocalisations by the female at the nest Nest, egg, incubation behaviour and parental care in the Huon and by her offspring are not documented in any wildlife Bowerbird Amblyornis germana. Australian Field Ornithology sound libraries. None of our recorded vocalisations of the 36, 18–23. female and her offspring match any of those described Frith, C.B. (1971). Some undescribed nests and eggs of New by Pratt & Beehler (2015). The intimate adult female Guinea birds. Bulletin of the British Ornithologists’ Club 91, calls documented at two nests and vocalisations by the 46–49. nestlings have not been previously recorded or described. Frith, C.B. & Beehler, B. (1998). The Birds of Paradise: Calls by a female attending a nestling and those of the Paradisaeidae. Oxford University Press, Oxford, UK. nestling presumably function to bond adult and young, and Frith, C.B. & Frith, D.W. (1990). Discovery of the King of Saxony Bird of Paradise Pteridophora alberti nest, egg and nestling, enhance adult–offspring recognition, and also female calls with notes on parental care. Bulletin of the British Ornithologists’ may stimulate nestling begging. Club 110, 160–164. Frith, C.B. & Frith, D.W. (1992). Nesting biology of the Short-tailed Acknowledgements Paradigalla Paradigalla brevicauda. Ibis 134, 77–82. We thank David Bishop, who suggested that RHD contact Frith, C.B. & Frith, D.W. (1993). The nesting biology of the Lisa Dabek to study robins in the YUS CA, Huon Peninsula. Ribbon-tailed Astrapia Astrapia mayeri (Paradisaeidae). Emu RHD thanks David Bryden for accompanying him on a 6-week 93, 12–22. exploratory trip to find a suitable study site. We thank our local Frith, C.B. & Frith, D.W. (1995). Notes on the nesting biology and guides, Keshdy Awa, George Sinao and Liberth Wesley, for diet of Victoria’s Riflebird victoriae. Emu 95, 162–174. finding nests and for their superb knowledge of their mountain Frith, C.B. & Frith, D.W. (2009). Family Paradisaeidae (birds- forests, and we thank the women of Gomdan for fresh fruit and of-paradise). In: del Hoyo, J., Elliot, A. & Christie, D.A. (Eds). vegetables. RHD’s late mother, Mrs E. Donaghey, financed most Handbook of the Birds of the World, Volume 14: Bush-shrikes of our avian research in Papua New Guinea. RHD thanks Darryl to Old World Sparrows, pp. 404–492. Lynx Edicions, Barcelona, Jones and the Griffith University Library, Queensland, for ongoing Spain. support. We thank Lisa Dabek, Mikal Nolan and Timmy Sowang Gill, F. & Donsker, D. (Eds) (2019). IOC World Bird List v. 9.2. of the Tree Kangaroo Conservation Program for facilitating our Available online: http://www.worldbirdnames.org (retrieved research in the YUS CA, which was inspired by the pioneering 2 January 2020). avian research there by Bruce Beehler, David Bishop, Jared Gilliard, E.T. (1969). Birds of Paradise and Bower Birds. Diamond, Alexandra Class Freeman and Benjamin Freeman. Weidenfeld & Nicolson, London. We thank Wendy Cooper and Thane Pratt for identifying the Guigueno, M.F. & Sealy, S.G. (2012). Nest sanitation in passerine Freycinetia. Our life-history studies in New Guinea are inspired by birds: Implications for egg rejection in hosts of brood parasites. the pioneering avian research of Cliff and Dawn Frith in montane Journal of Ornithology 153, 35–52. Huon Astrapia incubation and nestling care 75

Inaho, B. (2012). Tree Species Composition and Population Mack, A.L. (1992). The nest, egg and incubating behaviour of a Structure at Three Elevation Sites at YUS Conservation Area Blue Bird of Paradise Paradisaea rudolphi. Emu 92, 244–246. in Papua New Guinea. BSc (Hons) thesis. Papua New Guinea Pratt, T.K. & Beehler, B.M. (2015). Birds of New Guinea. 2nd edn. Institute of Biological Research, Goroka, PNG, and University Princeton University Press, Princeton, New Jersey, USA. of Papua New Guinea, Port Moresby, PNG. Scholes, E., Gillis, J.M. & Laman T. (2017). Visual and acoustic Irestedt, M., Jønsson, K.A., Fjeldså, J., Christidis, L. & components of courtship in the bird-of-paradise genus Astrapia Ericson, P.G. (2009). An unexpectedly long history of sexual (Aves: Paradisaeidae). PeerJ 5, e3987. selection in birds-of-paradise. BMC Evolutionary Biology 9, 235. Laman, T. & Scholes E. (2012). Birds of Paradise: Revealing the Received 10 February 2020, accepted 26 March 2020, World’s Most Extraordinary Birds. National Geographic Books, published online 2 July 2020 Washington DC, USA. Ligon, R.A., Diaz, C.D., Morano, J.L., Trosciako, J., Stevens, M., Moskeland, A., Layman, T. & Scholes, E. (2018). Evolution of correlated complexity in the radically different courtship signals of birds-of-paradise. PLoS Biology 16, e2006962.