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Home , African openbill, Asian openbill, Black stork, Ciconia, Ephippiorhynchus, Greater adjutant

110 AUSTRALIAN Field Ornithology 2009, 26, 110–115 review— The Black-necked asiaticus: An Overview

GREG. P. CLANCY Division of , School of Environmental and Rural Sciences, University of New England, Armidale, New South Wales 2351 [Present address: P.O. Box 63, Coutts Crossing, New South Wales 2460 (Email: [email protected])]

Summary Nineteen species of stork (Ciconiidae), belonging to three tribes, occur throughout the world, mostly in tropical areas. Some are migratory, some are colonial nesters and most are dependent on . Four to five species are considered threatened globally. The Australasian populations of the Black-necked Stork Ephippiorhynchus asiaticus are likely to be split from the Asian populations in the future, as the Satin Stork E. australis. Recent research on the species in New South Wales covering its distribution and territories, breeding biology, feeding behaviour and diet, threats and status, will be published in detail elsewhere.

Introduction Nineteen stork species, ranging from 75 cm to 152 cm in length, of the order Ciconiiformes, suborder Ciconiae and family Ciconiidae, are found throughout the world, with the greatest diversity in the tropics. Six species belong to the tribe Mycteriini (wood and openbills), seven species to the tribe Ciconiini (‘typical’ storks), and six species to the tribe Leptoptilini (‘giant’ storks) (del Hoyo et al. 1992). The Black-necked Stork Ephippiorhynchus asiaticus (and Satin Stork E.a. australis) belong to the last tribe, which also includes the Saddlebill E. senegalensis, Jabiru , javanicus, L. dubius and Marabou L. crumeniferus. This tribe shows a classic Gondwanan distribution pattern with species occurring in , , and . Some stork species are migratory, some are colonial nesters and some are dependent on wetlands (del Hoyo et al. 1992) (Table 1). Seventeen of the 19 species are piscivorous, at least occasionally. Some are highly specialised in their diet, with the openbills Anastomus spp. possessing bills especially modified to break open aquatic snails, and Abdim’s Stork abdimii feeding almost exclusively on army worms Spodoptera exempta (del Hoyo et al. 1992). Twelve species are colonial and six are solitary nesters, with one species, the Jabiru, mostly solitary. Fourteen are migratory or partially so, and one is nomadic. Four species, including the Black- necked Stork, are resident, with a further seven species partly resident. Only four species are not dependent on wetlands, although a further four are occasionally found away from wetlands (Table 1).

Conservation status Four or five stork species are threatened globally (IUCN List of Threatened ), with 14 considered of least concern (not threatened) although a few of VOL. 26 (4) december 2009 Black-necked Stork: An Overview 111

Table 1: Characteristics and of the world’s storks. Source: del Hoyo et al. 1992.

Species Length (cm) Dieta Nestingb Resident/ Conservation migrantc dependent statusd Tribe: Mycteriini 83–102 F,V,I C M yes LC ­ Mycteria americana 95–100 F,V C ?M yes V M. cinerea -billed Stork 95–105 FR,F C R/PM yes LC M. 93–102 F,V,I C R/PM yes LC M. leucocephala 81 S,V,I C R/PM yes LC Anastomus oscitans 80–94 S,V,I,F C M/PR mostly LC A. lamelligerus Tribe: Ciconiini 95–100 F,I,V S M/PR mostly LC Ciconia nigra Abdim’s Stork 75–81 I,V C M no LC C. abdimii Woolly-necked Stork 86–95 F,V,I S R mostly LC C. episcopus Storm’s Stork 85 F,?V,?I S ?R yes I (?E) C. stormi 97–102 FR,F,V,I C ?M mostly LC C. maguari European 100–102 V,I,F C M no LC C. ciconia Oriental White Stork 110–115 F,V,I S M yes e C. boyciana Tribe: Leptoptilini Black-necked Stork 110–137 F,V,I S R yes LC (?E) Ephippiorhynchus asiaticus Satin Stork 110–137 F,V,I S R yes LC E.a. australis Saddlebill 145–150 F,V,I S R yes LC E. senegalensis Jabiru 122–140 F,V,I MS N yes LC Jabiru mycteria Lesser Adjutant 110–120 F,V,I C R,N,M yes V Leptoptilos javanicus Greater Adjutant 120–152 Ca,F,V,I C N,M no e L. dubius Marabou 115–152 Ca,F,V,I C R,N,M no LC L. crumeniferus aF = , V = other , I = invertebrates, FR = , S =snails, Ca = bC = colonial, S = solitary, MS = mostly solitary cM = migrant, R = resident, PM = partial migrant, PR = partial resident, N = nomadic dLC = least concern, V = vulnerable, E = endangered, I = indeterminate AUSTRALIAN 112 CLANCY Field Ornithology these are ‘near threatened’ and one is considered to be potentially ‘endangered’, two are vulnerable, two are endangered and one has an indeterminate status but is potentially endangered (Table 1). Indeterminate means that the species is endangered, vulnerable or rare but there are insufficient data to determine the appropriate category. The potentially ‘endangered’ species are the Black-necked Stork in and Storm’s Stork Ciconia stormi. The threatened species cover a wide size range, three are solitary and three are colonial nesters, and all eat fish, as do most storks. Two are migrants or probably so, two are resident or probably so, one has resident, migratory and nomadic populations, and one has nomadic and migratory populations. The one common factor is an Asian distribution. Human population pressure in the form of the loss of stork feeding and breeding , and , may threaten these species. Alternatively, or additionally, the limited number of birdwatchers and researchers in these areas could also account for limited records of species, which may exaggerate rarity.

Australia’s stork species The Black-necked Stork is a large, iconic species found throughout northern Australia, and down the eastern coast to about Sydney, New South Wales. It is also found in southern New Guinea and parts of southern and south-eastern Asia. It is commonly referred to as ‘Jabiru’ in Australia, but this is confusing as this name properly refers to the Jabiru of South America. Taxonomically, the nominate subspecies Ephippiorhynchus asiaticus asiaticus is found in Asia, with in Australia and New Guinea being considered to be a separate subspecies E.a. australis (Marchant & Higgins 1990). Recent genetic work has indicated that the Asian and Australasian subspecies are distinct enough genetically to be considered separate species, although a more extensive dataset with better-documented specimens is required to confirm this (Christidis & Boles 2008). If confirmed, Australasian birds would be known as Ephippiorhynchus australis. My recommended common name of ‘Satin Stork’ has been adopted by the Birds Australia Common Names Committee (Andrew Ley pers. comm.), assuming that full specific status is confirmed. The Black-necked Stork is 110 to 137 cm in length and weighs ≥4 kg (Marchant & Higgins 1990). Despite its large size, distinctive appearance and widespread distribution in Australia, it has been rarely studied and there are few publications on its ecology (Marchant & Higgins 1990). Feeding behaviour, -sites and threats to the species have been discussed (Purcell 1993; Dorfman et al. 2001). Purcell (1993) identified the following research priorities: • assessing the rate of wetland loss in the Richmond Valley, New South Wales; • assessing the impact of exotic plants on the rate of wetland loss or decline; • identifying all Stork nest-sites in the Richmond Valley; • recording the breeding success of the Stork so as to aid in the modelling of population trends; • the development of a better understanding of the behaviour of the Stork in the Richmond Valley, with particular reference to breeding behaviour; VOL. 26 (4) december 2009 Black-necked Stork: An Overview 113

• assessing the impact of powerline strikes on populations of the Stork in the Richmond Valley; • assessing the impacts of environmental on Stork mortality and fecundity, with particular reference to pesticides and heavy metals; • investigating the potential of livestock dip-sites to act as a point source for wetland pollution; • attempting, by observation rather than experimentation, to determine the environmental factors that limit the population of the Stork in the Richmond Valley; and • assessing what role, if any, movement plays in the maintenance of local populations of Storks. Most of these priorities have been partly addressed in my research (Clancy 2008). Dorfman et al. (2001) concluded that changes in land-use patterns are likely to be one of the most important influences on the species, in addition to powerlines and pollutants, and suggested that the Cane Toad Bufo marinus may also pose a threat. The Stork’s distribution in Australia is reported in journals and newsletters, including extralimital records from south-western Queensland and north-eastern South Australia (Baxter et al. 2001) and New South Wales (Bell 1963; Salmon 1965). In the Alligator Rivers Region of the Northern Territory there was an estimated regional population of about 1800 Storks (Morton et al. 1993). The total population for New South Wales was estimated to be 37–43 Storks (Salmon 1965).

The Black-necked Stork globally The Black-necked Stork’s status, feeding behaviour, population size, detectability and habitat utilisation are known in India and Nepal (Rahmani 1989; Baral 1995; Maheswaran & Rahmani 2001, 2002; Sundar 2003, 2004, 2005; Ishtiaq et al. 2004; Maheswaran et al. 2004). This stork has declined in India, although some populations are stable or marginally increasing in some areas (Maheswaran 2004). It is difficult to locate and monitor as it forages in water of various depths, which influences its foraging behaviour. Globally, the Black-necked Stork has declined in parts of its range, with loss or pollution of wetlands and hunting pressure, and is listed as ‘Near Threatened’, almost meeting criterion C1 of the International Union for the Conservation of Nature (IUCN). There has been some recent discussion on whether it warrants a ‘Vulnerable’ listing (BirdLife International website 2002). If the species is split into two, the Asian species will probably meet the criteria for listing as Endangered or Vulnerable but the Australasian species (Satin Stork) will probably be globally secure (Least Concern). The large population in northern Australia has probably not been affected by development pressure although global climate change, including reduced rainfall and sea-level rises, may pose a threat. There is concern for the species in the southern part of its range, where it is listed as Endangered in New South Wales, because of the small population size and apparent decline (Dorfman et al. 2001). AUSTRALIAN 114 CLANCY Field Ornithology

The Black-necked Stork in New South Wales Given its perceived small and declining population in New South Wales, the species was studied there from 2003 to 2006 (Clancy 2008) to collect a range of biological and ecological information. The specific aims were to map current and historical distribution, Stork habitat and individual territories, and investigate breeding biology, feeding behaviour and diet, and habitat use. The breeding biology study investigated the reproductive biology of the species (breeding season, frequency of breeding, nest-site selection, nest- and , incubation, brood size, nestling period, nest productivity, post-fledging dependence), with emphasis on the differences between years. Other aspects of breeding behaviour, such as displays, mating, and incubation and brood sharing, were also studied. The aim of the feeding behaviour and diet study was to quantify feeding behaviour (foraging techniques, water depth, time of day, foraging success, handling of food and interaction with other birds), and diet (species hunted and captured, the size and weight of prey and the type of food fed to nestlings). I also considered what factors might be threatening the New South Wales population, such as accidental deaths from striking powerlines, and assessed its current status and likely future trends. A key conservation objective for such a regionally rare species is to establish whether the species is in decline and what aspects of its breeding biology, feeding behaviour, diet and habitat use could be targeted to make its status more secure. The findings of this study will be published elsewhere (Clancy in press).

Acknowledgements This review was prepared as part of my PhD thesis at the University of New England, Armidale, NSW. Hugh Ford and Richard Kingsford supervised this project, which was funded by an Australian Postgraduate Allowance. The Waterbird Society provided a grant to assist with travel costs during the fieldwork.

References Baral, H.S. (1995), ‘Black-necked Stork endangered’, Newsletter for Birdwatchers 35, 74–75. Baxter, C.I., Reid, J.R.W. & Jaensch, R.P. (2001), ‘First South Australian records of the Black-necked Stork Ephippiorhynchus asiaticus and occurrence of vagrants in south- western Queensland’, South Australian Ornithologist 33, 164–169. Bell, H.L (1963), ‘Distribution of the Jabiru in south-eastern Australia’, Emu 63, 201–206. BirdLife International (2002), Website http://www.birdlife.net Christidis, L. & Boles, W.E. (2008), Systematics and of Australian Birds, CSIRO Publishing, Melbourne. Clancy, G.P. (2008), Ecology, Conservation and Management of the Black-necked Stork Ephippiorhynchus asiaticus australis, PhD thesis, University of New England, Armidale, NSW. Clancy, G.P. (in press), ‘The distribution of the Black-necked Stork Ephippiorhynchus asiaticus australis in New South Wales since 1790’, Corella 34. del Hoyo, J., Elliott, A. & Sargatal, J. (Eds) (1992), Handbook of the Birds of the World, vol. 1, Lynx Edicions, Barcelona. Dorfman, E.J., Lamont, A. & Dickman, C.R. (2001), ‘Foraging behaviour and success of Black-necked Storks (Ephippiorhynchus asiaticus) in Australia: Implications for management’, Emu 101, 145–149. VOL. 26 (4) december 2009 Black-necked Stork: An Overview 115

Ishtiaq, F., Rahmani, A.R., Javed, S. & Coulter M.C. (2004), ‘Nest-site characteristics of Black-necked Stork (Ephippiorhynchus asiaticus) and White-necked Stork (Ciconia episcopus) in , Bharatpur, India’, Journal of the Bombay Natural History Society 101, 90–95. Maheswaran, G. & Rahmani, A.R. (2001), ‘Effects of water level changes and wading bird abundance on the foraging behaviour of Blacknecked Storks Ephippiorhynchus asiaticus in Dudwa National Park, India’, Journal of Bioscience 26, 373–382. Maheswaran, G. & Rahmani, A.R. (2002), ‘Foraging behaviour and feeding success of the Black-necked Stork (Ephippiorhynchus asiaticus) in Dudwa National Park, Uttar Pradesh, India’, Journal of Zoology (London) 258, 189–195. Maheswaran, G., Rahmani, A.R. & Coulter, M.C. (2004), ‘Recent records of Black-necked Stork Ephippiorhynchus asiaticus in India’, Forktail 20, 112–116. Marchant, S. & Higgins, P.J. (Eds) (1990), Handbook of Australian New Zealand and Antarctic Birds, vol. 1, Oxford University Press, Melbourne. Morton, S.R., Brennan, K.G. & Armstrong, M.D. (1993), ‘Distribution and abundance of Brolgas and Black-necked Storks in the Alligator Rivers Region, Northern Territory’, Emu 93, 88–92. Purcell, J.K. (1993),The Biology and Management of the Black-necked Stork (Ephippiorynchus [sic] asiaticus) in the Richmond Valley of NSW, unpublished student report for Faculty of Resource Science and Management, University of New England, Northern Rivers, Lismore, NSW. Rahmani, A.R. (1989), ‘Status of the Black-necked Stork Ephippiorhynchus asiaticus in the ’, Forktail 5, 99–110. Salmon, H.A. (1965), ‘Distribution of the Jabiru in central and northern coastal New South Wales’, Emu 65, 149–151. Sundar, K.S.G. (2003), ‘Notes on the breeding biology of the Black-necked Stork Ephippiorhynchus asiaticus in Etawah and Mainpuri districts, Uttar Pradesh, India’, Forktail 19, 15–20. Sundar, K.S.G. (2004), ‘Group size and habitat use by Black-necked Storks Ephippiorhynchus asiaticus in an agriculture dominated landscape in Uttar Pradesh, India’, Bird Conservation International 14, 323–334. Sundar, K.S.G. (2005), ‘Effectiveness of road transects and wetland visits for surveying Black-necked Storks Ephippiorhynchus asiaticus and Sarus Cranes Grus antigone in India’, Forktail 21, 27–32.

Received 27 April 2009 