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Australian Field Ornithology 2017, 34, 91–94 http://dx.doi.org/10.20938/afo34091094

First nesting pair of Little morphnoides recorded in the Sydney region

J. Walsh1* and C.T. Beranek2

127 Mahogany Boulevard, Warriewood NSW 2102, 2School of Environmental and Life Sciences, The University of Newcastle, Callaghan NSW 2308, Australia *Corresponding author. Email: [email protected]

Abstract. Although the Little Hieraaetus morphnoides is broadly distributed across much of Australia, it appears to be declining in . The key threatening process is the removal of , leading to loss of suitable nesting and foraging sites and changes in prey abundance. Here we present the first report of successful nesting of the Little Eagle in greater Sydney (i.e. in the County of Cumberland), and recommend guidelines for management. The , discovered in a Smooth-barked Apple Angophora costata in the suburb of Ingleside on 15 October 2016, was visited one to three times per week, and observations on behaviour, diet and habitat of the Eagles were noted. The most common prey taken was the European Rabbit Oryctolagus cuniculus. The chick fledged atc . 9 weeks old. The nest-site is at risk from a proposed development in the area and needs to be adaptively managed to ensure the continued presence and nesting of this species at this site.

Introduction prey abundances. Since European settlement, most woodland in NSW has been removed (Lunney 2004), and The Little Eagle Hieraaetus morphnoides is a small, this has been implicated in sharp declines of the native robustly built raptor that is found over much of Australia prey species of the Little Eagle (Van Dyck & Strahan 2008; in a patchy distribution (Debus 2012). It is absent from Olsen et al. 2010). Under such conditions, the Little Eagle areas of high urbanisation and dense , and is more can shift its diet from native to introduced species such as abundant in open woodland (Marchant & Higgins 1993). the rabbit (Debus et al. 2007; Olsen et al. 2010, 2013b), It is occasionally recorded in Sydney, New South Wales and it is known to shift its diet in arid and tropical areas to (NSW) (Atlas of Living Australia 2017), but is uncommon. mainly and/or (Meathrel 1990; Fisher 2010; To our knowledge, from all available data and consultation Aumann et al. 2016). This enables it to adapt to changing with experienced birdwatchers (Alan Morris pers. comm. availability of prey species, but it appears less able to cope and others), nesting has not been documented in greater with severe habitat alterations caused by urbanisation, Sydney (i.e. the County of Cumberland, which stretches especially immediately surrounding nest-sites (Olsen & from Broken Bay in the north, the Hawkesbury River in Fuentes 2005). Therefore, conservation of nest-sites and the north-west, the Nepean River in the west, the Cataract the habitat around these, including foraging areas, is a key River in the south-west and the northern suburbs of priority in mitigating declines (ACT Government 2013). Wollongong in the south). The nesting biology of the Little Eagle is well documented. The Little Eagle appears to be in decline in NSW and are typically 14–20 m above ground in large the Australian Capital Territory (ACT) (Debus et al. 2013). eucalypts in dense woodland adjacent to open habitat Comparison of Atlas of Living Australia records indicates (Marchant & Higgins 1993; Debus & Ley 2009). Pairs a 39% reduction in an index of abundance in NSW from of Eagles occupy territories estimated at 1600 ha from c. 1981 to 2001 (Barrett et al. 2007), and ~70% reduction nesting densities and inter-nest distances (Debus 1984). in NSW over 20 years to 2006 (Cooper et al. 2014). In However, the only radio-tracked breeding male occupied the ACT, the number of breeding pairs declined from 13 a much larger summer home-range (>5000 ha) on the in the 1980s to only two in 2005 (Olsen & Fuentes 2005). rural fringe of expanding suburbs of the ACT (Brawata & Recent surveys indicate that the population has stabilised Gruber 2016; Olsen et al. 2017). The breeding cycle from in the ACT but is still much lower than in the 1980s, with nest building to fledging is typically 4 months (Debus 1984, only two or three active nests in 2014–2016, and that 2011): eggs are usually laid in mid September, and young breeding productivity has also declined (Olsen et al. 2015, are fledged by January (Debus 1984; Debus et al. 2007). 2017). Because of these declines, it has been classed as Vulnerable in both NSW and the ACT, and a case has been Here, we provide the first documented account of made for up-listing the species to Endangered in the ACT successful nesting by the Little Eagle in Sydney, including (ACT Government 2013; Olsen et al. 2013a). It would also the timing of incubation and fledging, together with now qualify as Endangered in NSW. observations of prey items and the surrounding habitat. We also discuss the risk posed by a nearby development to Several key threatening processes in this decline have the persistence of this breeding site, and suggest possible been identified. There is evidence that competition with ways that the impacts can be mitigated. Wedge-tailed Eagles Aquila audax can prevent breeding of the Little Eagle (Olsen et al. 2010). Secondary poisoning from pindone baiting of Rabbits Oryctolagus cuniculus Methods is also a likely factor (Olsen et al. 2013a). However, the main threat is the removal of habitat, which can make The nest was discovered by JW on 15 October 2016, nest-sites unsuitable, remove foraging space and alter and thereafter was visited by JW and CB one–three 92 Australian Field Ornithology J. Walsh & C.T. Beranek

Results

The Little Eagles’ nest was located within Ingleside Chase Reserve (33°41′S, 151°17′E) ~20 m above ground on the near-horizontal fork of a Smooth-barked Apple Angophora costata (Figure 1). It was ~1.5 m × 1.5 m in diameter and was situated in the centre of a minor gully on a slope facing south-east. Habitat in the immediate area is Hawkesbury Sandstone Woodland with a canopy predominantly of Black She-oak Allocasuarina littoralis, Smooth-barked Apple, Red Bloodwood Corymbia gummifera, and Turpentine Syncarpia glomulifera. The nest was located near an ephemeral creekline. The surrounding habitat used by the pair of Little Eagles is a mixture of farmland, Hawkesbury Sandstone Heath, Hawkesbury Sandstone Open and medium/high-density housing. Within a 2.27-km radius of the nest-site (i.e. an area of ~1600 ha) there are 751 ha of rural housing, 575 ha of bushland and 265 ha of medium/high-density housing. Figure 1. The first recorded Little Eagle nest in Sydney, New South Wales: Ingleside Chase Reserve, December Observations are presented in Table 1. Observations 2016. Photo: Jayden Walsh of predation by the Little Eagles were infrequent, with seven observations over 17 h, and were mainly recorded opportunistically in an area of Hawkesbury Sandstone times per week, with each observation session lasting Woodland and open farmland. Prey items seen were four c. 45 minutes. Notes on adult and juvenile activity included rabbits, two unidentified birds, and one Eastern Water nestling growth, habitat use by adults, and opportunistic Dragon Intellagama lesueurii lesueurii. observations of predation, feeding and presence of food items. Observations of Little Eagles within the suburbs of Ingleside and Warriewood were also recorded. As nesting Discussion Little Eagles are sensitive to human disturbance (Debus et al. 2007; Debus & Ley 2009; Debus 2011), the observation The general properties of the Ingleside Chase Reserve position was selected to minimise disturbance. The nest nest-site are consistent with descriptions from elsewhere. was observed discreetly, using binoculars and a spotting The nest is within the typical range of 14–20 m above scope, from 60 m away, which the adults tolerated without ground (Debus et al. 2007; Debus & Ley 2009), but the alarm. nest-tree species (Smooth-barked Apple) has not been

Table 1. Observations on Little Eagles, Ingleside Chase Reserve, Sydney, New South Wales: behaviour of and hunting by the adults and development of the young. Dates are given as day, month, year.

Date Observations Adults Development of young Sept.–Nov. 2015 2 adults observed feeding on several occasions; prey items included Eastern Water Dragons and rabbits. On 15.11.15, calling was heard from vicinity of 2016 nest-site. 15.10.16 1641 h: nest discovered by JW; light morph adult was sitting on nest. Unknown. 16.10.16 0824 h: 2 adults (1 light morph, 1 dark morph) soaring, then diving above 1 chick in nest c. 1 day old; very small, nest-site. completely white and downy. 17.10.16 0940 h: Adult performing undulating flight display. Very small, white and downy. 18.10.16 0922 h: Half-eaten rabbit located 30 m away from nest. Not visible. 22.10.16 1411 h: 1 adult on nest. Chick slightly larger but still white and downy. 3.11.16 0710 h: Both adults flying close to nest-site. Chick c. 3 weeks old, fluffy, small/ medium size, 30% fully fledged size. 9.12.16 1804 h: 1 adult patrolling slope, and perched on Smooth-barked Apple at Fluffy medium-sized, 80% fully fledged top of slope, emitting calls. size. 1834 h: Adults soaring and prospecting in circles high over nest. 1846 h: Adult calling while gliding over north-eastern sandstone outcrop. 12.12.16 1930 h: 1 adult attending nest. Large chick, 90% fully fledged size. 17.12.16 1908 h: 1 adult perched in Red Bloodwood. Chick large with developed flight- feathers, fully fledged size. 19.12.16 1816 h: No adults observed. Chick fledged. 23.12.16 1720 h: Adult brought rabbit to nest. Chick flying short distances (~50 m). 1750 h: Last sighting of Little Eagles for 2016–2017 season at study site. Little Eagle: First nest in Sydney region, New South Wales 93

reported previously (Debus 1984; Debus et al. 2007, 2013) these areas for Little Eagles, artificial perches could be although it is structurally similar (tall, with a thick trunk) to incorporated into the landscape (Hall et al. 1981). Further, other known nest-trees (Debus et al. 2007; Debus & Ley pest-control management should not involve poison-based 2009). rabbit control (especially pindone), to remove the risk of secondary poisoning from eagles feeding on debilitated or The development of the Little Eagle chick was also dead rabbits (Olsen et al. 2013a). Lastly, a wide buffer from consistent with previous observations. When first seen, it any proposed development or planned burn should protect was estimated to be 1 day old. By the time of fledging, it the nesting site and foraging grounds. The fact that the was 64 ± 2 days old, giving a nestling period of c. 9 weeks, adults have been observed foraging up to 3 km from the which is in accord with the literature (Olsen & Fuentes nest suggests that urbanisation should not encroach into 2005; Debus et al. 2007; Debus & Ley 2009; Fisher 2010; the foraging habitat within at least that radius. Debus 2011). Observations of hunting by the Little Eagles were rarely Acknowledgements recorded, probably because of access restrictions and local We would like to thank Lucas Bluff, Jerry Olsen, Susan Trost, topography. Most late-afternoon observations of the adults Stephen Debus and Julia Hurley who all contributed reviews to were within 100 m of the nest-site, whereas opportunistic greatly improve the manuscript. sightings between 0800 and 1600 h were made up to 3 km away, where the Eagles were observed actively hunting and, in one instance, soaring over a dead Swamp Wallaby References Wallabia bicolor. If the adults ranged 3 km from the nest- ACT Government (2013). Little Eagle (Hieraaetus morphnoides). site in most directions, their home-range could have been at Action Plan No. 35. ACT Government, . least 2800 ha and possibly more, given that radio-tracking Atlas of Living Australia (2017). Available online: www.ala.org.au reveals a larger range than that estimated from sightings (retrieved 2 May 2017). Aumann, T.A., Baker-Gabb, D.J. & Debus, S.J.S. (2016). Breeding and nest densities (cf. Brawata & Gruber 2016; Olsen et diets of four raptor species in the Australian tropics. Corella al. 2017). Although only seven observations were made 40, 13–16. of the Eagles taking prey, 57% of prey items were rabbits, Barrett, G., Silcocks, A., Cunningham, R., Oliver, D., Weston, M. as expected in areas where rabbits are abundant (Olsen & Baker, J. (2007). Comparison of atlas data to determine the et al. 2010, 2013b). Most observations of predation were of species in New South Wales, with made at the end of a rural road adjacent to Fern Creek and an emphasis on woodland-dependent species. Australian surrounded by woodland, which is likely to be the main Zoologist 34, 37–77. Brawata, R. & Gruber, B. (2016). Movements of the Little Eagle hunting site for the Eagles at this study site. (Hieraaetus morphnoides) Surrounding the Proposed Although the Little Eagle has never previously been Riverview Development Area, Australian Capital Territory. recorded nesting in the Sydney area (as defined here), Report by Institute for Applied Ecology, University of Canberra, there was an apparent breeding attempt just outside the Canberra. Cooper, R.M., McAllan, I.A.W. & Curtis, B.R. (2014). An Atlas County of Cumberland in 1978 (Atlas of Living Australia of the Birds of New South Wales & the Australian Capital 2017). Hoskin et al. (1991) also reported a breeding Territory, Volume 1: Emu to Plains-wanderer. NSW Bird record at Cobbitty in 1978, and the Atlas of Living Australia Atlassers Inc., Sydney. records an observation of eggs from Camden South on Debus, S. (1984). Biology of the Little Eagle on the Northern 3 September 1978; it is likely that these two sources refer to Tablelands of New South Wales. Emu 84, 87–92. the same event, but as the eggs were collected (most likely Debus, S. (2011). Parental time budgets and breeding behaviour only a short period after being laid), the nesting attempt of the Little Eagle Hieraaetus morphnoides in northern New South Wales. Corella , 65–72. was probably not successful. The precise location is just 35 Debus, S. (2012). Birds of Prey of Australia: A Field Guide. CSIRO to the south-west of the Sydney area in Camden South Publishing, Melbourne. (34°4′S, 150°42′E), but there has been no subsequent Debus, S. & Ley, A. (2009). Aspects of the breeding cycle of record of the species breeding there, probably because of the Little Eagle Hieraaetus morphnoides. Australian Field increases in urbanisation. Ornithology 26, 76–99. Debus, S., Hatfield, T., Ley, A. & Rose, A. (2007). Breeding Land management and future development in the biology and diet of the Little Eagle Hieraaetus morphnoides in Ingleside area must take into consideration the Little the New England region of New South Wales. Australian Field Eagle’s declining population status, its rarity in the Ornithology 24, 137–157. Sydney area, and its sensitivity to habitat loss and human Debus, S., Olsen, J., Judge, D. & Butterfield, M. (2013). Numbers disturbance. Continued successful breeding in this territory of breeding Little Eagles Hieraaetus morphnoides in the might influence the viability of the Eagle population in Australian Capital Territory in relation to atlas counts. Corella 37, 30–32. the greater Sydney area. In this context, existing plans Fisher, K.D. (2010). Breeding and diet of the Little Eagle to build ~4000 homes for an additional 10 000 residents Hieraaetus morphnoides in central Queensland. Australian in Ingleside (immediately west and north-west of the Field Ornithology 27, 119–127. current nest-site) pose a significant risk to the local Eagle Hall, T.R., Howard, W.E. & Marsh, R.E. (1981). Raptor use of population. This project is occurring ~500 m away from artificial perches. Wildlife Society Bulletin (1973-2006) 9, the Little Eagle nest, will affect a total of 700 ha of land, 296–298. and will involve the loss of 320 ha of bushland. However, Hoskin, E.S., Hindwood, K.A. & McGill, A.R. (1991). The Birds given the use of open spaces by this species, the effective of Sydney, County of Cumberland, New South Wales, 1770 - 1989. Surrey Beatty & Sons, Sydney. habitat loss will exceed the 320 ha of bushland to be Lunney, D. (2004). A test of our civilisation: Conserving Australia’s cleared. We propose that this area should be managed forest fauna across a cultural landscape. In: D. Lunney, (Ed.). in its current form or improved to facilitate this species’ Conservation of Australia’s Forest Fauna. 2nd edn, pp. 1–22. method of hunting. For example, to enhance habitat in Royal Zoological Society of NSW, Sydney. 94 Australian Field Ornithology J. Walsh & C.T. Beranek

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