Australian Field Ornithology 2012, 29, 182–188

Dancing clowns: Display behaviour between two White- faced Robins leucops

John Rawsthorne1* and Richard Donaghey2

110 Macartney Street, Fannie Bay NT 0820, Australia 280 Sawards Road, Myalla TAS 7325, Australia *Corresponding author. Email: [email protected]

Summary. Elaborate courtship and agonistic behaviours are common in some avian families. Here we describe an observation of ritualised ‘dance’ behaviour for the White-faced Robin Tregellasia leucops (Petroicidae) from Cape York Peninsula, Queensland. We also describe territorial and copulation behaviour for this in the same region. It is unclear whether the ritualised dance behaviour is agonistic, courtship, or serves some other purpose. This is the first record of such a ritualised behaviour amongst the Australo-Papuan robins.

Introduction The White-faced Robin Tregellasia leucops (Petroicidae) is a small 15-g yellow robin with a black head and distinctive clown-like white face and chin (front cover, Figure 1). It typically inhabits tropical rainforests and vine thickets, particularly near watercourses. The Australian subspecies T.l. albigularis mainly inhabits lowland tropical rainforest in a small area of north-eastern Cape York Peninsula, Queensland, and nine other subspecies are distributed widely throughout the foothills and lower mountains of New Guinea, mainly from 600 to 1650 m above sea-level (Boles 2007). This species is sedentary and individuals may be long- lived; a long-term banding study recorded survivorship of up to 18 years and an annual survival rate of 75% for adults (Coleman et al. 2012). The Australian

Figure 1. White-faced Robin, Iron Range National Park, Qld. Photo: Stuart Rae White-faced Robin dance 183 subspecies breeds from September to January (Higgins & Peter 2002; RD pers. obs.), but its social organisation and behaviour, breeding biology, and foraging behaviour and ecology are poorly documented (Higgins & Peter 2002). Diamond (1972), Croxall (1977) and Coates (1990) provided more information on foraging ecology and behaviour, altitudinal segregation and habitat of the species in New Guinea, but little about social behaviour.

Observations

Ritualised dancing behaviour of two White-faced Robins On 24 November 2011, JR visited the fringe of rainforest at Iron Range National Park in Far North Queensland, where the Portland Road crosses the Claudie River (12°45′S, 143°17′E). The immediate area was cleared grassland, with a 200-m-wide strip of rainforest along the Claudie River connecting two larger areas of forest. It was ~20 minutes after sunset and becoming dark. No moon was visible but, with little cloud, there was a lingering twilight, and JR’s eyes were well adjusted to the low light. He observed the following with Leica Ultravid 10 × 32 binoculars, from a distance of ~20 m. Two White-faced Robins were present, one on each side of the road, adjacent to a road bridge over the Claudie River. Both were on bare ground on the road verge, and vocalising loudly, ~5 m apart. The sounds from each included chipping, churring and harsher growling sounds. Identification was unambiguous, based on both the excellent view of the two and the chipping and churring calls, which JR had heard many times while in the Iron Range rainforest for the previous week. Both birds had full adult plumage, but it was not possible to discern gender. JR did not detect any other birds present throughout the following observations. After ~30 seconds, both birds puffed up the feathers on their bodies, appearing almost completely round with heads protruding but tails and wings barely evident. The bird on the western side of the road (hereafter ‘W bird’) hopped across the road pavement, and approached the other bird (located on the eastern side of the road, the ‘E bird’) until the birds were ~1.5 m apart. The W bird was churring with its head held downwards at an angle of 45° and it held this fixed posture as it hopped. The E bird then reciprocated with a similar display, moving on to the road pavement to face the W bird at a distance of ~10 cm, maintaining the same head and body posture and making similar calls. Both birds then began co-ordinated movements, initially a series of advances and retreats with the two birds maintaining their close separation of ~10 cm. The movements were precise and closely reciprocated, with the birds hopping forwards and backwards over ~50 cm. The only variations were head postures— the two birds variously holding their heads either up at 45° above horizontal or down at 45° below horizontal. These backwards/forwards movements occurred at intervals of ~5 seconds. Both birds held ‘up’ and ‘down’ head postures, but these head postures were not at any stage strictly reciprocal. After ~1–2 minutes the movements changed. The W bird proceeded to hop in 184 Australian Field Ornithology J. Rawsthorne & R. Donaghey an anticlockwise circle while the E bird watched. The circular path was ~50 cm in diameter and went back towards the western edge of the road, hence not encircling the E bird but leaving the E bird to watch from outside the circle. When the W bird was a little more than halfway around this circle (at ~210°), it then twirled 360° on the spot, before continuing to complete the circle. The E bird watched, motionless, from outside the circle. At the end of the circular dance, the two birds then faced each other again, churred and bobbed heads up and down (varying between the ‘up’ and ‘down’ postures). Body feathers were puffed up throughout. The W bird repeated this circular dance, with all aspects repeated precisely including the twirl at 210°. The E bird then reciprocated, reproducing all movements of the W bird (although JR did not record whether the E bird hopped clockwise or anticlockwise), while the W bird watched. After the E bird’s circular dance, the W bird performed the circular routine a third time. At this point a car approached, and the two birds separated and flew back to the forest on their respective sides of the road. There was no further activity that evening, which was the last day of JR’s visit to Iron Range National Park, so no further observations were made. The entire episode lasted ~5 minutes, from the time the two birds were first detected to when the dance ended.

Territorial agonistic interaction between two White-faced Robins RD and Carolyn Donaghey intensively studied the breeding behaviour of a colour- banded population of White-faced Robins in the Gordon Creek area of Iron Range National Park (12°43′S, 143°18′E) from 7 September to 16 December 2005. The focus of the study was to elucidate the breeding system and parental care behaviour, and they discovered that breeding pairs and groups are sedentary, territorial and respectively have a pair or co-operative breeding system. Cyclone Monica ripped through Lockhart River in April 2006 so they returned to Iron Range in mid October 2006 for 2 months, mainly to determine the survival of colour-banded robins and to make further observations. At Gordon Creek there was a high density of White-faced Robins and much agonistic behaviour, such as threats and chasing, and vocalisations. At 0855 h on 4 November 2006, RD watched, with binoculars from a distance of ~40 m, two adult unbanded White-faced Robins interacting in the middle of the road at the first Gordon Creek campsite. The two robins faced each other ~30 cm apart. The nearest bird, on the southern side of the road (hereafter the ‘S bird’), had the feathers of its body puffed out and both quivering wings held out ~1 cm from the body and below the tail. The second bird, located on the northern side of the road (the ‘N bird’), also had its body feathers fluffed out, but the wings were held against the body. The S bird approached closer, as did the N bird, until they were 10 cm apart. The S bird then pounced at its rival with feet outstretched. For an instant both birds were locked together on the ground with their feet on each other’s breasts. Then they separated, flew up 2 m and descended to the ground, facing each other 1–2 m apart. The S bird had its body feathers fluffed up and its lower back arched. The N bird turned sideways, away from the S bird, and flew into rainforest bordering the northern side of the road, and the S bird flew White-faced Robin dance 185 into rainforest on the southern side of the road. Fighting and subsequent flights to different territories confirmed that this interaction was a territorial dispute, presumably between two males. During RD’s intensive study of White-faced Robins at Iron Range in 2005, the most common male–female interactions observed were courtship feeding of a female by a male during nest-construction, incubation and early nestling periods. Courtship and incubation feeding have been documented for 20 Australo-Papuan robin species (Higgins & Peter 2002) and have been observed in another four species (RD pers. obs.). RD observed one copulation event in White-faced Robins: there was no preliminary ‘dance’ nor elaborate pre-copulatory displays, and the female solicited copulation by crouching on a perch with her body horizontal and wings quivering.

Discussion The behaviours described herein have not been previously documented for White- faced Robins (Higgins & Peter 2002; C.B. Frith pers. comm.). The behaviours recorded by RD in 2005 and 2006 are consistent with copulation and territorial behaviours for other Australo-Papuan robins, and so their interpretation is uncontroversial. However, the ritualised ‘dance’ behaviour observed by JR in 2011 is unusual, and despite the additional context provided by RD’s observations, its function remains ambiguous. JR’s impression of the initial noisy twilight interaction between the two birds in 2011 was of a territorial dispute. However, this became ambiguous as the interaction proceeded and the more elaborate reciprocal behaviours unfolded. The repetition and precise choreography of the behaviours, along with the two-stage modular dance, evoked thoughts of a courtship dance between a male and a female. Another possibility is that the dance was some other form of familial interaction, but ambiguity remains, and the possibility of a territorial dispute remains valid. Crepuscular activity may not be unusual for White-faced Robins. The sub-family epithet for this species, Eopsaltriinae, means ‘dawn singer’, perhaps indicating a relative preference for low-light conditions. Indeed, in mist-netting operations White-faced Robins (at Iron Range) and Eastern Yellow Robins australis (in south-eastern Australia) are disproportionately more often captured early in the morning or close to dusk (JR pers. obs.), and White-faced Robins are the first diurnal dawn singer at Iron Range (RD pers. obs.). Although the Pale- yellow Robin Tregellasia capito is noted to seek roosts 15–30 minutes before last light (Huggett 2000), there are no published accounts of roosting or other crepuscular activity of White-faced Robins. It is not known whether the White- faced Robin has eyes relatively larger than other robins living in similarly dense forest that are known not to be crepuscular. To attempt to place the ritualised ‘dance’ behaviour in context, we have examined recorded behaviours for other Australo-Papuan robins. There are no similar observations for the congeneric Pale-yellow Robin, which has been studied in more detail (Huggett 2000; Higgins & Peter 2002). Amongst the Petroicidae, similar elements of agonistic and sexual behaviour have been documented for the 186 Australian Field Ornithology J. Rawsthorne & R. Donaghey

Red-capped Robin goodenovii and two robins, the New Zealand P. macrocephala and P. traversi (Higgins & Peter 2002). There are several such behaviours recorded for the Red-capped Robin. First, Serventy (1927, p. 272) noted ‘...two of these Robins, male and female, on the ground, advancing and retiring before each other as if they were engaged in a dance. Both birds displayed equal animation, twittering the while’. Second, Dowling (2003, p. 542) recorded that territorial disputes amongst males are sometimes resolved by ‘a stand-off on the perch, with one male advancing a short distance (up to 40 cm), while the other male retreated a similar distance. Both males moved back and forth on the perch for some time, before one flew off’. Third, ‘characteristic circular flights’ of males around a perched female are made during courtship, both in aviaries and in the wild (Hutton 1991; Dowling 2003). Fourth, Donaghey (in Higgins & Peter 2002) noted that, while females were incubating, neighbouring males engaged in territorial threat displays, on the ground or on low perches. Two adult males faced each other from 30 cm to 1 m apart, advanced and retreated, flicked wings and gave sharp metallic zzidit or zzid-dit-da calls. In the New Zealand Tomtit, the breeding female solicits food from her mate when she leaves the nest. She adopts a begging posture, fluffing up the feathers on her body, ruffling or fluttering wings, and crouching on a perch with head thrust forward. This begging posture appears to be submissive (Wilkinson 1930; Higgins & Peter 2002). The Black Robin of New Zealand’s performs courtship flights with the male closely following the female, and subsequently attempting to mount her (Higgins & Peter 2002). Higgins & Peter (2002, p. 278) stated that the ‘Male can also perform an excited “dance” round female, which also may lead to copulation’. It is intriguing that both male–female courtship and male–male agonistic behaviour in these two robins and the Red-capped Robin incorporate some features similar to JR’s observations of the more complex and elaborate displays of the White-faced Robin. However, none of the previous authors described a dance with two distinct stages, as observed by JR, and there are no similar observations for any other robins during twilight periods. There are several possible interpretations of the dance display of White-faced Robins observed by JR. First, was this a male–female interaction? Male–female interactions include pair-formation, pair maintenance such as courtship feeding, and mating behaviour including extra-pair copulations. In common with many of the tropics and the Southern Hemisphere, White-faced Robins are sedentary and presumably long-lived, so pair-bonds and territories tend to be stable (Greenberg & Gradwohl 1986; Morton & Stutchbury 2000; Stutchbury & Morton 2001; Russell et al. 2004) relative to Northern Hemisphere migratory passerines. In long-lived, sedentary birds pair-formation is infrequent but could occur at any time of year when one member of a pair dies or if there is a separation. Hence there are few opportunities for observing pair-formation in the breeding season. Extra-pair copulation cannot be ruled out, but its extent in Australo- Papuan robins is unknown. Based on RD’s observation of a copulation event, extra-pair copulations may be brief and without elaborate display. However, published observations of male–female courtship and mating behaviour in three robin species suggest that agonistic and sexual elements can be incorporated in White-faced Robin dance 187 courtship and mating behaviour. It is unclear whether the dance display described herein was between a male and a female, or whether it was between two males in the absence of a female or in the presence of a female not seen by the observer, or between two females. Was the dance display of White-faced Robins an agonistic territorial dispute between two males? The first stage of the display observed by JR involved fluffed- up birds on the ground advancing and retreating. This behaviour is similar to an agonistic territorial dispute observed by RD in White-faced Robins and similar to territorial boundary disputes in Red-capped Robins. The head-bobbing and circular movements observed by JR have similarities to courtship behaviour in the Red-capped Robin and Black Robin, suggesting that this may have been sexual behaviour. Thus the dance display appears to have both agonistic and sexual elements.

Conclusion We have recorded a complex behaviour of White-faced Robins previously unreported for this or related species. We have also recorded copulation and agonistic territorial behaviours for the species. On balance, especially considering the breeding system and parental care of known Australo-Papuan robins, and the crepuscular behaviour and high density of White-faced Robins at Iron Range, RD’s observation of a territorial dispute, and the known agonistic territorial behaviour in Red-capped Robins, we consider that the ritual dance behaviour observed by JR was most likely an exaggerated territorial dispute between two males. However, since the sex of the two dancing White-faced Robins was unknown, we cannot discount the possibility of a sexual display. Further detailed observations of birds of known sex and/or territory performing the complex ritualised dance behaviour described here would be needed to correctly interpret its function and frequency.

Acknowledgements Cliff Frith, Richard Noske and Phil Gregory provided helpful comments that placed these observations in context and greatly improved the manuscript. Terry Korodaj and David Watson helped to develop ideas within the manuscript.

References Boles, W.E. (2007). Family Petroicidae (Australasian robins). In: del Hoyo, J., Elliot, A. & Christie, D.A. (Eds). Handbook of the Birds of the World, Volume 12: Picathartes to Tits and Chickadees, pp. 438–488. Lynx Edicions, Barcelona. Coates, B.J. (1990). The Birds of Papua New Guinea. Volume II. Passerines. Dove Publications, Brisbane. Coleman, J.T., van Gessel, F.W. & Clayton, M. (2012). Longevity and movements in the White-faced Robin (Tregellasia leucops albigularis) in Iron Range National Park, Cape York. Sunbird 42, 11–23. Croxall, J.P. (1977). Feeding behaviour and ecology of New Guinea rainforest insectivorous passerines. Ibis 119, 113–146. Diamond, J.M. (1972). Avifauna of the Eastern Highlands of New Guinea. Publications of the Nuttall Ornithological Club, No. 12. Nuttall Ornithological Club, Cambridge, Massachusetts, USA. 188 Australian Field Ornithology J. Rawsthorne & R. Donaghey

Dowling, D.K. (2003). Breeding biology of the red-capped robin. Australian Journal of Zoology 51, 533–549. Greenberg, R. & Gradwohl, J. (1986). Constant density and stable territories in some tropical insectivorous birds. Oecologia 69, 618–625. Higgins, P.J. & Peter, J.M. (Eds) (2002). Handbook of Australian, New Zealand & Antarctic Birds, Volume 6: Pardalotes to Shrike-thrushes. Oxford University Press, Melbourne. Huggett, A.J. (2000). An experimental study of the impact of gaps and clusters silviculture on insectivorous birds in a continuous forest landscape. PhD thesis. University of New England, Armidale, NSW. Hutton, R. (1991). Australian Softbill Management. Singil Press, Sydney. Morton, E.S. & Stutchbury, B.J.M. (2000). Demography and reproductive success in the Dusky Antbird, a sedentary tropical . Journal of Field Ornithology 71, 493–500. Russell, E.M., Brown, R.J. & Brown, M.N. (2004). Life history of the white-breasted robin, Eopsaltria georgiana (Petroicidae), in south-western Australia. Australian Journal of Zoology 52, 111–145. Serventy, D.L. (1927). New records from the Swan River District, Western Australia. Emu 26, 269–272. Stutchbury, B.J.M. & Morton, E.S. (2001). Behavioral Ecology of Tropical Birds. Academic Press, London. Wilkinson, A.K. (1930). Some habits of the North Island Tomtit. Emu 30, 102–104.

Received 30 May 2012

Editor’s note: Fifty years of publishing in The Australian Bird Watcher/ Australian Field Ornithology—1962 to 2012

The publication of two articles (Gosper 2012; Rawsthorne & Donaghey 2012) in this issue of Australian Field Ornithology marks a significant contribution to the journal. Both Dennis Gosper and Richard Donaghey had published articles in this journal in December 1962 (Donaghey 1962; Gosper 1962), exactly 50 years earlier to the issue. The discovery of this milestone was serendipitous: Gosper had informed me upon acceptance of his article that his first article in The Australian Bird Watcher was published nearly 50 years ago. Upon checking volume 1, issue 8, I realised that the article following Gosper’s in 1962 was by Donaghey, who had just had his White-faced Robin paper accepted. Ley (2011) recently highlighted the support from contributors to the journal over long time periods, but a 50-year span is, as far are we are aware, a record. Congratulations to both authors.

References Donaghey, R.H. (1962). The White-throated Warbler of Blue Gum Creek, Chatswood, N.S.W. Australian Bird Watcher 1, 228–233. Gosper, D. (1962). Breeding records of the Koel. Australian Bird Watcher 1, 226–228. Gosper, D.G. (2012). Contributions to the reproductive effort in a group of plural-breeding Pied Butcherbirds Cracticus nigrogularis. Australian Field Ornithology 29, 169–181. Ley, A. (2011). Forty-four years of The Australian Bird Watcher, 1959–2002. Australian Field Ornithology 28, 142–149. Rawsthorne, J. & Donaghey, R. (2012). Dancing clowns: Display behaviour between two White-faced Robins Tregellasia leucops. Australian Field Ornithology 29, 182–188.

James Fitzsimons