REFERENCES AUSTRALIA S RAPTORS DIURNAL BIRDS OF PREY AND OWLS

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REFERENCES General texts: Debus, S. (1998), Birds of Prey of Australia: A Field Guide, OUP, Melbourne. Higgins, P. J. (ed.) (in press), Handbook of Australian, New Zealand and Antarctic Birds, vol. IV, Parrots to Dollarbird, OUP, Melbourne. Hollands, D. (1984), Eagles, Hawks and Falcons of Australia, Nelson, Melbourne. Hollands, D. (1991), Birds of the Night: Owls, Frogmouths and Nightjars of Australia, Reed, Balgowlah. Marchant, S. & Higgins, P. J. (1993), Handbook of Australian, New Zealand and Antarctic Birds, vol. II, Raptors to Lapwings, OUP, Melbourne. Olsen, P. (1995), Australian Birds of Prey, University of New South Wales Press, Sydney. Schodde, R. & Mason, I. (1981), Nocturnal Birds of Australia, Lansdowne, Melbourne. Specific references: 1. Blakers, M., Davies, S. J. J. F & Reilly, P. N. (1984), The Atlas of Australian Birds, MUP, Melbourne. 2. Baker-Gabb, D. J. & Steele, W. K. (1996), ‘Monitoring the relative abundance, distribution and movements of Australian birds of prey’, Australian Nature Conservation Agency Project no. FPP 110, RAOU, Melbourne. 3. Collar, N. J., Crosby, M. J. & Stattersfeld, A. J. (1994), Birds to Watch 2: The World List of Threatened Birds, Birdlife Conservation Series no. 4, Birdlife International, Cambridge. 4. Hill, R. (1996), A Recovery Plan for the Christmas Island Hawk-Owl, RAOU, Melbourne. 5. Hill, R. (1996), A Recovery Plan for the Christmas Island Goshawk, RAOU, Melbourne. 6. Olsen, P. (1997), Recovery Plan for the Norfolk Island Boobook Owl Ninox novaeseelandiae undulata, Environment Australia, Canberra. 7. Gaffney, R. F. & Mooney, N. J. (1992), The Wedge-tailed Eagle Recovery Plan: Management Phase, Department of Parks, Wildlife and Heritage, Hobart. 8. Anon. (nd), Living with Wildlife (one each on eagles and hawks), Tasmanian Parks and Wildlife Service, Hobart. 9. Maciejewski, S. E. (1997), ‘The Grass Owl Tyto capensis in north-eastern New South Wales’. In: G. Czechura & S. Debus (eds), Australian Raptor Studies II, Birds Australia Monograph no. 3, RAOU, Melbourne, pp. 54–70. 10. Debus, S. J. S. & Chafer, C. J. (1994), ‘The Powerful Owl Ninox strenua in New South Wales’, Australian Birds 28 (supplement), pp. 21–38. 11. Kavanagh, R. P. & Bamkin, K. L. (1995), ‘Distribution of nocturnal forest birds and mammals in relation to the logging mosaic in south-eastern New South Wales, Australia’, Biological Conservation 71, pp. 41–53. 12. Kavanagh, R. P., Debus, S. J. S., Tweedie, T. & Webster, R. (1995), ‘Distribution of nocturnal forest birds and mammals in north-eastern New South Wales; relationships with environmental variables and management history’, Wildlife Research 22, pp. 359–77. 13. Silveira, C. E. (1997), Targeted Assessments of Key Threatened Vertebrate Fauna in Relation to the North-east and Benalla–Mansfield Forest Management Area (one each on Barking Owl, Sooty Owl and Powerful Owl), Arthur Rylah Institute, DNRE, Melbourne. 14. Robinson, D. & Traill, B. (1996), Conserving Woodland Birds in the Wheat and Sheep Belts of Southern Australia, RAOU Conservation Statement no. 10, RAOU, Melbourne 15. Debus, S. J. S. (1997), ‘The Barking Owl in New South Wales’, Australian Birds 30, pp. 53–80. 16. Anon. (1998), Report to RCD Management Group, March 1998, National RCD Monitoring and Surveillance Program and Epidemiology Program, Bureau of Resource Sciences, Canberra. 17. Olsen, P. (1998), Australia’s Pest Animals: New Solutions to Old Problems, Kangaroo Press, Sydney. 18. Olsen, P., Fuller, P. & Marples, T. G. (1993), ‘Pesticide-related eggshell thinning in Australian raptors’, Emu 93, pp. 1–11. 19. Avian Power Line Interaction Committee (1996), Suggested Practices for Raptor Protection on Power Lines: the State of the Art in 1996, Edison Electric Institute and Raptor Research Foundation, Washington, DC. 20. Hess, J. F., Holdsworth, M. & Mooney, N. (1996), ‘Reducing

Birds Australia Conservation Statement No. 2

bird electrocution and collision mortality due to power assets: the Wedge-tailed Eagle Aquila audax and Grey Goshawk Accipiter novaehollandiae in Tasmania, Australia’. In: 2nd International Conference on Raptors, Urbino, Italy, October 1996, Raptor Research Foundation, Provo. 21. Gaffney, R. (1994), ‘Community support to manage forests for nesting Wedge-tailed Eagles Aquila audax fleayi in Tasmania’. In: A. Norton (ed), Conserving Biological Diversity in Temperate Forest Ecosystems, Centre for Resource and Environmental Science, Australian National University, Canberra, pp. 87–8. 22. Mooney, N. J. & Taylor, R. J. (1996), ‘Value of nest site protection in ameliorating the effects of forestry operations on the Wedge-tailed Eagle in Tasmania’. In: D. Bird, D. Varland & J. Negro (eds), Raptors in Human Landscapes, Academic Press, New York, pp. 275–82. 23. Olsen, P. & Olsen, J. (1978), ‘Alleviating the impact of human disturbance on the breeding Peregrine Falcon: I. Ornithologists’, Corella 2, pp. 1–7. 24. Holdsworth, M. & Marmion, P. (1993), ‘Raptors and education in Tasmania’. In: P. Olsen (ed), Australian Raptor Studies, Australasian Raptor Association, RAOU, Melbourne, pp. 220–6. 25. Norman, J., Christidis, L., Westerman, M. & Hill, F. A. R. (in press), ‘Molecular analysis confirms the species status of the Christmas Island Hawk-Owl Ninox natalis’, Emu. 26. Norman, J., Olsen, P. & Christidis, L. (in press), ‘Molecular genetics confirms taxonomic affinities of the endangered Norfolk Island Boobook Ninox novaeseelandiae undulata’, Biological Conservation. 27. Aumann, T., Mooney, N. J. & Olsen, P. D. (1989), ‘The legal status of birds of prey in Australia’. In: B.-U. Meyburg & R. D. Chancellor (eds), Raptors in the Modern World, World Working Group on Birds of Prey, Berlin, pp. 591–6. 28. Brereton, R. N. & Mooney, N. J. (1994), ‘Conservation of the nesting habitat of the Grey Goshawk (Accipiter novaehollandiae) in Tasmanian State Forests’, Tasforests 6, pp. 79–91. 29. Jackson, J. & Taylor, R. (1994), Threatened Fauna Manual for Production Forests in Tasmania, Forest Practices Board, Hobart. 30. Garnett, S. (ed.) (1993), Threatened and Extinct Birds of Australia, RAOU Report no. 82, RAOU and ANPWS, Canberra.

by Penny Olsen

CONSERVATION THROUGH KNOWLEDGE

415 Riversdale Road, Hawthorn East, Vic. 3123 Tel: (03) 9882 2622; Fax: (03) 9882 2677 Email: [email protected] Birds Australia Home Page: http://www.vicnet.net.au/~birdsaus Founded in 1901, Birds Australia (Royal Australasian Ornithologists Union) is Australia’s oldest national conservation organisation, dedicated to the study and conservation of native birds and their habitat. New members are welcome.

Australasian Raptor Association The Australasian Raptor Association (ARA) is a semi-autonomous group of Birds Australia. It was founded in 1979 to act as a focus for those with an interest in diurnal and nocturnal raptors of the Australian region. The ARA’s broad aims are to promote raptor research, conservation and management and to foster communication and co-operation in the region. For further information, contact Birds Australia National Office. ARA Home Page: http: //www.tasweb.com.au/ara/index.htm

Wingspan is the quarterly membership magazine of Birds Australia. Additional copies of this Conservation Statement are available from the National Office.

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AUSTRALIA’S RAPTORS: DIURNAL BIRDS OF PREY AND OWLS

ACN 004 076 475

Birds Australia Conservation Statements provide information about issues relating to the conservation of Australasian birds and their habitat, and suggest solutions to problems.

December 1997 / W I N G S PA N

White-bellied Sea-Eagle in its element. Wilderness areas, conserved for the benefit of all their inhabitants, are the most natural way to leave space for raptors. Photo by Ford Kristo

SUMMARY: Raptors (birds of prey) fall into two natural groups, diurnal species and owls, which have similar habits, but are unrelated. As predators they are important components of ecosystems, but this role sometimes brings them into conflict with humans, both as perceived pests and as untargeted victims of programs to control other pests. Discounting rare vagrants, Australia and its territories host 35 species of birds of prey: 24 diurnal raptors and 11 owls, many of which are endemic. Nine species and as many subspecies are listed as threatened nationally and/or regionally. Unobtrusive but vigilant management, through the preservation of adequate areas of well-maintained habitat, is the critical conservation priority for all species. This not only involves protection of relatively undisturbed habitats, but better management of agricultural land and harvested forests according to the principles of ecologically sustainable development, and more conservationconscious development of residential areas, to the benefit of all users, including raptors. Disturbance of nest sites should be avoided, particularly those of threatened species and subspecies. For a few taxa, such as the Norfolk Island Boobook and the Tasmanian subspecies of Wedge-tailed Eagle, the protection and maintenance of individual nest sites is essential. Other areas of need are: research into the status and conservation requirements of some species, and the identification of significant breeding and wintering areas; research into the consequences of management initiatives, such as fire regimes, grazing pressure and pest management on raptors and other wildlife; education to increase understanding of raptors’ ecological role and intrinsic value; and promotion of the use of raptor-safe techniques and poisons to control pests, and of non-destructive measures to minimise livestock losses to raptor predation. Supplement to Wingspan, vol. 8, no. 3, September 1998

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Habitat degradation is thought to have restricted the breeding range of the Grey Falcon more or less to the arid zone, warranting the need for special research into the falcon’s status and conservation requirements. Little is known of raptor ecology in arid and northern Australia. Photo by Lindsay Cupper

Birds Australia Conservation Statement

FOR THE PURPOSES OF THIS CONSERVATION STATEMENT raptors are defined as birds that survive largely by eating other animals, captured with heavily taloned feet. This definition encompasses both the diurnal birds of prey and the owls, groups united by similar habits and ecological roles but otherwise unrelated. A shared characteristic is that females of all diurnal species and most owls are larger than males, as much as twice as heavy in a few species. In Australia, the exceptions are the three large hawk-owls, in which the male is clearly larger. Nevertheless, the four families of diurnal birds of prey (Families Accipitridae and Falconidae) and owls (Strigidae and Tytonidae) are distinguished by anatomical, behavioural and ecological differences. The accipitrids, known colloquially as hawks, kites, harriers, vultures and eagles, are rather similar in basic structure, but they have wide ecological radiation, reflected in a diversity of sizes, shapes, flying abilities and predatory habits. They are closely related to the falconids, represented in Australia by the falcons, perhaps the most distinctive group of diurnal birds of prey. Falcons resemble hawks, and share such characteristics as a hooked beak, fleshy cere, a crop, and two ovaries (unlike other birds), but differ in other significant ways, such as their habit of immobilising prey with a bite to the neck and their lack of nest-building instinct. Typically, members of the two families are largely active by day, although some are also crepuscular and one, the Letter-winged Kite, is largely nocturnal. By contrast the owls are primarily active by night. Most have cryptic plumage and feathers adapted for silent flight; all have reversible outer toes and usually perch with two toes forward, two back. The tytonids, with a distinctive heart-shaped facial disc, asymmetrical ear openings and rather small eyes, make great use of sound cues for hunting. The Australian strigids all belong to the genus Ninox, the hawk-owls. As the name suggests, they are more hawk-like than other owls, with a proportionately smaller head and indistinct facial disc. Symmetrical ear openings and larger eyes distinguish them from the tytonids, and they are more dependent on sight for hunting.

Australia’s Raptors: Diurnal Birds of Prey and OwlsDecember 1997 / W

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THE AUSTRALIAN SPECIES Australia and its territories host 35 species of raptors (see Table 1. p. IV), plus a few vagrants of other species. Eleven species are endemic to Australia, another 17 are endemic to Australasia and only seven are more cosmopolitan in distribution. This is a high level of regional endemism but an unexceptional number of species. Nevertheless, certain groups are particularly well represented. For example, about 16 per cent of the world’s falcon species and about one-third of the species of both Tyto and Ninox occur in Australia. The country’s open flatness may help to explain the first, and the second may be related to the diversity of small to medium-sized nocturnal mammal species that Australia once supported.

ECOLOGY In general, raptors tend to be long lived, with low reproductive rates and low population densities. As they are at the top of food chains, they can be limited by the availability of their prey. These and other traits make them particularly vulnerable to human impact. For example, populations of large, slow-breeding eagles are sometimes unable to compensate for high losses through persecution.

Distribution and habitat Raptors are distributed Australia-wide. The distribution of a particular species is intimately linked to its habitat requirements: species with specialised requirements have more limited distributions than those that tolerate a variety of conditions. Several raptors frequent a variety of habitats and occur almost Australia-wide, including Tasmania and other large offshore islands. These include the Nankeen Kestrel, Brown Falcon, Wedge-tailed Eagle, Brown Goshawk, Collared Sparrowhawk and Southern Boobook. In the 1977–81 Atlas of Australian Birds project,1 the Brown Falcon and Nankeen Kestrel were the most widely encountered of all birds, each reported from 95 per cent of the 1-degree blocks used to divide the country. The Wedge-tailed Eagle fell sixth, in 86 per cent, and two other raptors, the Whistling Kite and Black Kite, were in the top 10 most widespread species for the Northern Territory. Other species, including the Australian Hobby, Brown Goshawk, Collared Sparrowhawk, Barn Owl and Southern Boobook are also widely distributed, but may not be sighted as easily. The most constrained in distribution are the Lesser Sooty Owl and the highly specialised Letter-winged Kite. In Australia, the owl occurs only between about Cooktown and Paluma, in north-east Queensland. The kite is more or less confined to the Coopers Creek drainage system, except sporadically, when its population increases and erupts in conjunction with its prey, the Long-haired Rat (Rattus villosissimus).

During the breeding season, a preference for long grasses and reeds (especially near swamps) in temperate areas limits the Swamp Harrier largely to the south-western and south-eastern mainland and Tasmania. However, in the non-breeding season it occurs in wetter areas across the mainland. The Powerful Owl and Sooty Owl are more or less confined to forested habitats east of the Divide. By contrast, the Square-tailed Kite and areas occupied by the Grass Owl are scattered over much of the mainland. However, the kite is limited by its need to breed in species-rich patches of woodland and the owl is confined to moist, open, tussocky grassland and similar habitats. Many widespread species are also abundant, for example the Brown Falcon, Australian Kestrel and Southern Boobook (see Table 1). By contrast, the Grey Falcon and Grass Owl both occur over a vast area but are nowhere common. Similarly, the widely distributed Red Goshawk, with an estimated 350 breeding pairs, is probably the rarest of the diurnal species. The Christmas Island Hawk-Owl is quite abundant but its total population is small, perhaps 600 pairs, because it is confined to an isolated island only 137 km2 in area.

Movements It is critical that we understand raptor movements, particularly for identifying points at which to apply conservation action. For example, in non-sedentary species or age groups, conservation problems can occur on the breeding grounds, on the non-breeding grounds or en route between.

In autumn many Australian Hobbies and other raptor species from the south-east make their way to northern Australia for the winter, possibly following the flocks of migrating passerines headed for milder climates. Movements of these and other Australian raptors are not well understood. Photo by Dave Watts

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Table 1. Estimated status and likely trends in the total population size of Australia’s raptors since European settlement. Species

General status

General change in total population size since settlement (and supposed major reason for change)

Osprey Pandion haliaetus Black-shouldered Kite Elanus axillaris Letter-winged Kite Elanus scriptus Pacific Baza Aviceda subcristata Square-tailed Kite Lophoictinia isura Black-breasted Buzzard Hamirostra melanosternon Red Goshawk Erythrotriorchis radiatus Black Kite Milvus migrans Brahminy Kite Haliastur indus Whistling Kite Haliastur sphenurus White-bellied Sea-Eagle Haliaeetus leucogaster

fairly common common rare–uncommon fairly common rare–uncommon fairly common rare-uncommon common–very common common common fairly common

Spotted Harrier Circus assimilis Swamp Harrier Circus approximans Brown Goshawk Accipiter fasciatus Grey Goshawk Accipiter novaehollandiae Collared Sparrowhawk Accipiter cirrhocephalus Wedge-tailed Eagle Aquila audax

uncommon common common fairly common fairly common common

Little Eagle Hieraaetus morphnoides Brown Falcon Falco berigora Black Falcon Falco subniger Grey Falcon Falco hypoleucos

common very common uncommon rare-uncommon

Australian Hobby Falco longipennis Nankeen Kestrel Falco cenchroides Peregrine Falcon Falco peregrinus

common very common common

Sooty Owl Tyto tenebricosa Lesser Sooty Owl Tyto multipunctata Masked Owl Tyto novaehollandiae

fairly common common in restricted range uncommon

Barn Owl Tyto alba Grass Owl Tyto capensis Powerful Owl Ninox strenua Rufous Owl Ninox rufa Barking Owl Ninox connivens Southern Boobook Ninox boobook New Zealand Morepork Ninox novaeseelandiae Christmas Island Hawk-Owl Ninox natalis

common uncommon common fairly common common very common rare (Norfolk I.) common

decrease (pesticides, persecution), but good recovery in recent years increase (moderate clearing, mice) — — decrease (clearing) — decrease (clearing, direct disturbance) increase (rubbish dumps, slaughterhouses, rabbits) slight decrease (persecution?, disturbance) decrease (pesticides, wetland alteration); some local increases (rabbits, rubbish tips) stable?: local increases (man-made reservoirs, etc., carp) and decreases (clearing, development) Decrease (degradation of arid zone?) — slight increase? (rabbits, moderate clearing); some areas apparent decrease eg. coastal NSW slight decrease (clearing, persecution?) — local increases (rabbits, moderate clearing); also local decreases (disturbance, persecution, clearing) increase (moderate clearing, rabbits, starlings?) slight increase ? (moderate clearing, rabbits, starlings, provision of permanent water) — decrease in distribution (habitat alteration) but perhaps not in status (provision of permanent water) slight increase? (provision of water, starlings, winter refugia in urban areas) increase (moderate clearing, mice, starlings) but local decreases (intensive agriculture etc.) decrease (pesticides, persecution) but recovery to slight increase (man-made nest sites, spread of Galahs, starlings, feral pigeons, permanent water) decrease (clearing) stable? stable in Tasmania; decrease in NSW, Victoria and Queensland (clearing, overgrazing, rodenticides) possible increase (moderate clearing, introduced rodents) suspected decrease (clearing, overgrazing, introduced predators, rodenticides) slight decrease (clearing) — decrease (clearing, overgrazing?) in more disturbed areas stable; local declines (clearing, overgrazing?) severe decrease (mainly clearing); hybrid population increasing (conservation assisted) decrease 25% (clearing, mining; now ceased); now stable

Status is ranked from very common to rare. The relative terms ‘rare’, etc. are used in a colloquial sense and refer to status within the usual range of each species and relate to its expected abundance. They acknowledge the fact that raptors are never common in the sense of, say, starlings. Thus, populations of the Tasmanian subspecies of the Wedge-tailed Eagle and the Christmas Island Hawk-owl may be more or less saturated (common), even though both are officially listed as threatened (Table 2) because they have such small populations that they are particularly vulnerable.

Much remains to be discovered about the movements of Australia’s raptors. Important wintering areas and drought refugia are only just beginning to be recognised.2 Across northern Australia, migrants probably outnumber residents during the dry winter. Significant wintering areas for the diurnal raptors appear to include the Kimberley, the Top End, the Gulf of Carpentaria drainage zone, Cape York Peninsula, the Darling Downs and some coastal and subcoastal areas of southern Australia. The north-west coast of Arnhem Land, and the Mitchell Grass Downs south to the Coopers Creek drainage basin are particularly important for the concentration of raptors they support in winter, and the Riverina in spring–summer. Inland ranges and associated lowlands probably also act as refugia for some species during drought: these include the Central Ranges, the Pilbara, the Flinders Ranges, the Selwyn Ranges and the central drainage system of Lake Eyre. No Australian species is wholly migratory. Almost the entire population of Swamp Harriers departs Tasmania for the winter, but elsewhere populations are only partially migratory. Indeed, many species are

partially migratory: each year part of the population moves to kinder climates for the winter and this causes a northward and/or coastward shift in distribution of the species. Partial migrants include the Black Falcon, Brown Falcon, Grey Falcon, Australian Hobby, Nankeen Kestrel, Brown Goshawk, Square-tailed Kite, Black-breasted Buzzard and Little Eagle. Other species are more nomadic or irruptive: for example, the Letter-Winged, Black-Shouldered and Black Kites, and the Barn Owl and Grass Owl. Still others – many of the owls, the Peregrine Falcon and White-bellied Sea-Eagle – are largely sedentary. It is likely that the movement patterns of some species have been influenced by human activity; for example, rubbish tips and abattoirs support populations of Black Kites that might otherwise move elsewhere.

Diet Raptors regurgitate pellets containing the less digestible portions of their prey. Depending on the acidity of the digestive system, these contain greater or lesser quantities of indigestible food elements such as


bone, hair, scales and invertebrate exoskeletons. Pellets offer a useful way to estimate diet. Most detailed studies of raptor diet have been conducted in the breeding season when prey is usually brought to the nest, and pellets and remains can be collected relatively easily from beneath. For most species the non-breeding diet is unstudied. All raptors are primarily carnivorous, taking mammals, birds, reptiles, fish, amphibians and insects. The Pacific Baza occasionally feeds on fleshy fruit, such as figs. Some, such as the fish-eating Osprey and the bird-eating Peregrine Falcon, are specialists. Others are more catholic in their diet. All species take mostly live prey, especially when breeding; only a few eat carrion regularly. Within a species, diet can vary markedly between regions, habitats, years and seasons, ages, sexes and individuals; availability of preferred prey is thought to account largely for the differences but is seldom easy to measure. For example, in summer, Swamp Harriers at Werribee, Victoria, are most dependent on mammalian prey; in winter the emphasis is on birds. In spring, Brown Falcons in Tasmania eat mostly mammals and birds; during summer, they switch to seasonally available insects and reptiles; in winter, they return to birds and mammals, but also carrion. Powerful Owls prey mostly on arboreal marsupials (possums and gliders), flying foxes when available, and the occasional roosting bird. Many species are most insectivorous in their first year or so of life (in general, there is less skill and risk involved in the capture of insects and they are more common than vertebrates), and for similar reasons juveniles of some species tend to eat more carrion than do adults.

Reproduction Raptors are particularly vulnerable when breeding, and some species are prone to desert nests or young when disturbed. The main months of breeding vary according to species, seasonal conditions, latitude and altitude. If disruptive human activity in a breeding area is necessary, preferably it should be undertaken outside this period. Because the falcons and owls are unable to build a true nest, they are more limited by the availability of nest sites than are species that can build nests themselves. Such dependence on tree hollows, on existing stick nests, or a limited number of cliffs with ledges, can be a species’ ‘Achilles heel’ and therefore a suitable point for concentrated conservation effort. For example, if mature trees with hollows are in short supply because of land degradation or clearing, then nest boxes may be a conservation solution. Most species nest as solitary, territorial pairs, although the Letter-winged Kite and Grass Owl, for instance, occasionally nest in loose colonies. The pairs of many species nest year after year at traditional nest sites or at least in the same area, facilitating census of breeding populations. Details of reproduction have great significance for conservation. For example, the naturally low

reproductive rate of larger species can slow recovery efforts. Drought-sensitive species, such as the Wedgetailed Eagle, may breed poorly in very dry years, whereas other species, such as the Peregrine Falcon, may be little affected. Both species are widespread and highly successful, but have different reproductive strategies. An understanding of such dynamics is important when assessing conservation issues.

Population status Human impact has led to a change in status of several species (see Table 1). Certain species may have benefited while others have suffered: several of the latter are now recognised as threatened either nationally and/or regionally (see Table 2, p. X). Settlement and clearing has adversely affected the distribution of some species. For example, the Red Goshawk and Brahminy Kite once occurred in New South Wales as far south as Sydney, but their range has shrunk northwards; the goshawk is now rarely seen only in the extreme north-east corner of the State. The Southern Boobook, once common on Lord Howe Island, no longer occur there. As undesirable as such changes are, in terms of the total population, no species of Australian raptor has undergone a critical change in distribution or status since European settlement. Persecution and pesticides all but removed the Osprey from New South Wales by the 1980s, but protection in the past decade has allowed it to return to much of its former range. Peregrine Falcon numbers, similarly reduced in certain areas by pesticides and persecution, have also recovered.

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The Lesser Sooty Owl, the most constrained in distribution of all Australia’s raptors, occurs only in a confined area of mountain rainforest in north-east Queensland. Like the falcons, the owls are unable to build a true nest; their dependence on nest hollows makes them particularly vulnerable to habitat loss. Photo by David Hollands

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THREATENED SPECIES

Australia’s rarest raptor and one of the rarest in the world, the Red Goshawk is estimated to have a total breeding population of only 350 pairs. A ‘hands-off’ management strategy is recommended for the secure population in Australia’s tropical north; more active research and conservation of habitat is needed for the subcoastal eastern population. Photo by Lindsay Cupper

Several Australian species are listed as threatened either internationally, nationally or by the States, with some variation in assessment criteria between organisations (see Table 2). Other species have been placed in working categories, which indicates concern and the need for vigilance over their status. For example, the Black Falcon and Letter-winged Kite are considered uncommon in South Australia, and Masked and Powerful Owls and the White-bellied Sea-Eagle are placed in a working category (rare) in the ACT (Nature Conservation Act 1994), as is the Grey Goshawk in Tasmania. Western Australia has a ‘priority’ list, used for management planning purposes, which includes the Barking Owl and Square-tailed Kite. Similarly, in Tasmania, the Masked Owl and White-bellied Sea-Eagle are given high priority for research and management. Usually, species listed are those that occur naturally in low numbers either because of small distributional range (Christmas Island HawkOwl) or low population density (Grey Falcon, Square-tailed Kite, Red Goshawk and Powerful Owl). Several subspecies are threatened and one, the Lord Howe Island Boobook (Ninox novaeseelandiae albaria), was extinct by 1950, apparently because of habitat destruction, introduced rats and predators. BirdLife International, which assesses full species only, categorises the Red Goshawk as endangered and the Square-tailed Kite, Grey Falcon and Powerful Owl as vulnerable.3 The Grey Falcon is listed as one of six Falconids considered at risk, and the Red Goshawk as one of 36 Accipitridae. Of the uniquely Australian species considered threatened, the Red Goshawk and Grey Falcon have always been uncommon. However, human impact on their habitats has caused shrinkage of their breeding ranges. Nevertheless, both species are probably secure

if existing habitat is preserved. The Square-tailed Kite is a widespread but sparsely distributed raptor. Destruction of the passerine-rich open forest and woodland it favours is a continuing threat to its survival. The Black-breasted Buzzard is poorly known; however, it is probably more common than previously supposed. A management plan has been prepared for the Christmas Island Hawk-Owl,4 which is now adequately protected and probably secure. Island subspecies of three otherwise common raptors are considered to be at risk. On Christmas Island, an Australian territory in the Indian Ocean, an unusual subspecies of Brown Goshawk may number less than 150 pairs. In the past, mining for phosphate destroyed about 25 per cent of the forest, and birds were shot. However, much of the island has been declared a national park, mining ceased in 1987, mined areas are being rehabilitated, and guns were banned in 1975. The goshawk seems secure but because the island cannot support a large population, it remains vulnerable. A study is required to assess the population’s viability and genetic identity. Management plans have been prepared for the goshawk5 and also for the Norfolk Island Boobook,6 which was reduced to one bird before action was taken, and now exists only as a hybrid subspecies, managed in the wild through the provision of nest boxes. Destruction of forests and persecution are the main conservation problems facing the Tasmanian subspecies of the Wedge-tailed Eagle.7 The subspecies usually breeds in forest and is prone to desert the nest when disturbed. Only about 20 per cent of the roughly 220 pairs breed on land with a high reservation status. Logging protocols, administered by the Tasmanian Forest Practices Unit and wildlife authorities, limit nest destruction and disturbance, but each year more and more nests are affected. Targeted education and legal protection have failed to halt the decline, and up to 30 per cent of each year’s juveniles and 5 per cent of adults are killed by shooting and poisoning. Greater liaison between conservation bodies, land owners and forest managers, wider education8 and harsher penalties for offences, should secure the future of the subspecies. Grass Owls may be adequately protected in north-eastern New South Wales by reserves;9 but elsewhere may be less secure. Large owls are particularly threatened by broadscale clearance of mature forests and tree loss in woodlands.10, 11, 12, 13 Leaving vegetation along creeklines, and mature seed trees, lessens the impact of forestry operations, but if logging continues at the present rate the long-term prognosis for these species is poor. Nevertheless, several positive steps have been taken, including the protection of corridors, the retention of unlogged zones and other reserves in wood production forests; the preservation of a system of conservation reserves in escarpment forests; the identification and assessment of areas to be added to the reserve system under the Comprehensive, Adequate and Representative (CAR) process of the


Regional Forests Agreements (RFA) plan; and the development of new harvesting protocols. Eighty per cent of Australia’s temperate woodlands have been cleared for agriculture, much remaining woodland is becoming increasingly degraded, and clearing is escalating in the less damaged tropical woodlands of Queensland.14 Although conservation action, particularly on islands, and increased knowledge have alleviated concerns for some threatened species, the trend is for more groups to be listed and none has been delisted. Recently, the White-bellied Sea-Eagle was listed in Victoria because of concern that habitat clearance, disturbance, persecution and accidental poisoning threaten its small population (c. 100 pairs). For similar reasons, the species has also been nominated for listing in Tasmania.

MAIN THREATS Several characteristics of raptors make them resistant to the processes leading to extinction. For example, in general they are highly mobile, the structure of their habitat is more important than the vegetational composition, and they have the ability to switch prey if appropriate alternatives are available. This has allowed some species to survive well in farmlands and cities, on introduced prey species, for instance. Other characteristics of raptor biology and physiology make them particularly vulnerable to extinction. As predators at the top of food chains they are vulnerable to secondary poisoning and the accumulation of persistent pesticides, and subject to persecution. Sometimes conservation problems are unexpected. For instance, raptors are more sensitive physiologically to the effects of DDT than are most other bird groups. To understand the dynamics and conservation needs of populations, a thorough knowledge of

mortality is important. Identifying vulnerable populations or subsets of populations, such as a particular age or sex group, and their threats, is vital. For example, the damaging effects of DDT (dichlor-diphenyl-trichlor-ethane) on some raptor populations went largely unrecognised for more than a decade: even though egg loss was causing many breeding failures, many long-lived adults were still present at their nest sites. Thus, recruitment into the breeding population is also one of the more critical life history characteristics, but it is also one of the least researched.

Habitat change Destruction, degradation and alteration of habitat is by far the most significant raptor conservation problem. The distribution of several species has shrunk following destruction of nesting and hunting habitat. For example, clearing, grazing and other degradation processes appear to have altered some semi-arid habitat so that it is now less suitable for Grey Falcons; since the 1950s, the eastern limit of the falcon’s distribution has shifted further inland in New South Wales. Habitat loss and degradation are also implicated in the worrying decline in Barking Owl numbers.15 Loss of trees and habitat continues through clearing for timber or firewood, lack of regeneration because of overgrazing and exposure, inappropriate fire management, increased insect attack in human-altered ecosystems, salination and residential development. Eventually this will have a profound effect on raptor populations deprived of suitable habitat, hunting perches, roost sites and nest sites. The loss of mature trees with holes for nesting is a critical concern for several owl species. Monocultures, such as plantations and broadacre cropland, provide suitable habitat for few species.

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This wooded hillside is typical of that favoured in south-east Australia as a nest-site by the Brown Goshawk. In south-eastern and south-western Australia, less than 10 per cent of the original woodland remains, putting all those birds which depend on them for feeding, shelter and nesting at risk. Habitat protection and restoration is the key long-term conservation priority for all raptor species. Photos by Penny Olsen

viii



Broadscale control of pests

One of the most managed of all raptors, the Osprey is a conservation success story. By the 1970s pesticides, persecution and habitat destruction had severely depleted many of the world’s populations. Banning the offending pesticides, nest site guarding and the provision of artificial nesting sites have restored most populations. In Australia the species now thrives. Photo by Lindsay Cupper

Raptors can suffer as untargeted victims of localised pest control programs intended to protect livestock or crops (see ‘Poisons’, below). Of greater concern is the nationwide control of rabbits or any other pest that is food for a variety of raptors. The interrelationship between predator and prey should be well understood before any such control program is commenced. The introduction and spread of the rabbit control agent myxomatosis in 1950 undoubtedly affected the dynamics of some raptor populations, as will the newer agent, rabbit calicivirus disease (RCD), which escaped into the wild rabbit population in 1995 and was spread by government authorities in 1996.16, 17 However, the disease is performing poorly in temperate areas, and even where it has been most effective, in arid and semi-arid areas, it has leapfrogged pockets of rabbits. Thus, at present, it seems unlikely that loss of rabbits to RCD will threaten the national population of any raptor species. Nevertheless, large areas now devoid of rabbits as well as native mammals may not support the numbers of Wedge-tailed Eagles and other predators of mediumsized mammals that they once did.

Poisons Poisoning of raptors can be intentional or accidental, as in the case of DDT used to control insects, or the taking of baits laid to manage pests such as foxes. Historical studies of the thickness of raptor eggshells show that certain species suffered thinning of their shells, particularly in the 1960s and 1970s.18

This would have caused local breeding failures, but appears not to have led to the dramatic declines in populations that occurred elsewhere in the world. Newer chemicals, such as organophosphates, that are designed to break down quickly to harmless substances have replaced DDT and other persistent pesticides, many of which were banned in the 1980s. However, some of the organophosphates have caused local raptor deaths by secondary poisoning, through consumption of poisoned rodents or birds. Occasionally, Wedge-tailed Eagles and other raptors are poisoned in attempts to protect lambs by the illegal use of baits laced with acute toxins such as strychnine, lucijet, phosdrin and alpha choralase, targeted at foxes, dingoes, ravens, Tasmanian Devils, and occasionally the raptors themselves. Similarly, small numbers of raptors are killed during poorly conceived broadscale poisoning to control mouse outbreaks. Contrary to popular belief, secondary poisoning of raptors is unlikely to occur from the use of 1080 to control herbivores in plantations and agricultural land. By contrast, there is cause for concern over secondary poisoning by brodifacoum, used to control rodents in sugar cane. Research on the environmental impact of the newer pesticides is needed. Occasionally, raptors are affected by other contaminants from human activities: for example, ingestion of lead shot from shotgun shells, PCB (polychlorinated biphenyl) seepage from garbage dumps, and mercury from industrial waste.

Persecution To protect the expanding sheep industry, in the past the Wedge-tailed Eagle was among the most persecuted of all raptors worldwide. A bounty system in some States encouraged the slaughter of tens of thousands of eagles annually. Nevertheless, like many persecuted raptors, the species proved remarkably resilient. Once such killing was made illegal, by 1971, populations recovered rapidly.


Deliberate destruction of raptors continues, usually because of their perceived damage to livestock (e.g. poultry, lambs, kids), aviary birds or racing pigeons, but occasionally as an act of vandalism. However, at current levels such persecution is local in impact and unlikely to affect populations.

Disturbance Some raptors, particularly the Wedge-tailed Eagle and Swamp Harrier, are sensitive to disturbance and will not nest close to human activity. If disturbed, for example by human visitation at the nest, these species often desert eggs and even nestlings. Other species vary in their level of intolerance of disturbance, but in general they are most prone to desert during the nest site selection period and least as the chicks near fledging. For example, White-bellied Sea-eagles are likely to desert during the pre-laying and incubation periods, but less likely to desert chicks. In general, disturbance above the nest is more threatening than that from below, and prolonged disturbance more serious than incidental.

Power poles, powerlines and windows Power poles provide vantage points, and occasionally nest sites, for raptors. However, some distribution lines are hazardous for medium to large species: if the bird simultaneously contacts two electrical wires (conductors or phases) or a single-phase and a ground wire, it is electrocuted.19, 20 Even small raptors are at risk from certain poletop configurations and transformers. On the other hand, the distance between the cables of large transmission lines is usually greater than a raptor’s wingspan and poses little risk, except, occasionally, to the largest species. Bundled insulated aerial cables rather than separate unprotected lines, insulation of closely spaced wires on the tops of poles, and the provision of safe perches are just some of the cost-effective means available to electrical suppliers to reduce the risk of electrocution. A reduction in electrocutions results in fewer outages and significant cost savings to power supply companies and consumers. 20 Perhaps more often, fast-flying raptors die or injure themselves through collision with the wires or electrical structures. As increasing amounts of land are taken up by rural development, the incidence of such collisions is likely to increase. Electrocution and collision are poorly researched in Australia

and, although probably not a significant conservation problem, their impact could be reduced. Collision with windows is also an increasing cause of mortality; research could yield ways to ameliorate the problem, particularly for large buildings. Lastly, many raptors are killed by collision with vehicles; the removal of road-killed animals on which raptors feed, so that they are well away from roads, would alleviate this problem.

CONSERVATION NEEDS Habitat protection and restoration is the most important long-term conservation action that can be taken. This entails setting aside significant areas of habitat, and ensuring their preservation and maintenance, as well as the appropriate management of non-reserved land, including that which is privately owned. Not only is the total area of habitat important, but so also is the degree of fragmentation (patch size and isolation). Core breeding habitats and wintering areas are vital, but other areas, where nonbreeders and juveniles can survive and gain experience before joining the breeding population, must also be conserved. Loss of one habitat implies an increase in another, new habitat. Some human-altered habitats, such as some agricultural land and sewage farms, also have great conservation value for breeding and overwintering resident and transient raptors. For such habitats to be effective, raptor necessities such as nest sites, roosts and hunting perches must be conserved or provided. Particularly in the vicinity of disturbance-prone species, human activities must be managed to minimise disruption.21, 22, 23 Various other measures can be taken to promote raptor survival, such as their protection from persecution and exploitation (e.g. harvesting by falconers or egg-collectors); and the reduction of incidental threats, including those from toxic chemicals, pesticides, electrocution on powerlines and accidental poisoning in campaigns directed at other species. European Honey Bees are an increasing problem in their appropriation of holes from tree-cavity nesters. The control of exotic predators, such as cats, may benefit certain species. However desirable, any broadscale control of introduced pests such as rabbits, mice or starlings may have a severe effect on dependent raptor populations. The powerful and pervasive interaction between native and exotic predators and prey is not well understood and should not be tampered with lightly. Since the late 1980s, in Australia the harmful organochlorine pesticides are now banned or their use has been severely restricted. However, several Australian raptors winter in New Guinea, where these chemicals are still widely and heavily applied; as yet, there is no evidence of any significant impact. There is a need for vigilance to ensure that newer, ‘safer’, replacement chemicals do not have any unforeseen deleterious effects.

I N G S PA N

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x


Brown Goshawk and rabbit prey. Although it seems at present unlikely that loss of rabbits to RCD will threaten the national population of any raptor species, large areas of the continent now devoid of rabbits as well as native mammals may not support the numbers of Wedge-tailed Eagles and other raptors that they once did. Photo by Nicholas Birks



raptors has little conservation value in itself. Nevertheless, the care and effort involved reinforce the notion that raptors have intrinsic worth as well as rights, and close contact allows many people a positive experience of raptors. In general, in situ preservation has proven to be more cost-effective than captive breeding. It entails the protection and enhancement of habitats and alleviation of threats, actions not necessarily associated with a captive-breeding program. Misplaced captive breeding can also drain resources and attention from more critical in situ conservation needs. Importantly, wild-based recoveries eliminate the special problems associated with the release of captives.

Education and research In Australia, lead poisoning from ingested lead shot used by hunters has caused some raptor deaths. There is lobbying for a change to steel shot because of the build-up of lead shot in some water bodies and its perceived threat to waterbirds and, through consumption of them, raptors. Eggs and nestlings have been stolen and occasionally adults are killed at nest sites. The keeping of raptors for sport (falconry) is not permitted in Australia, and only a few individuals licensed through museums are allowed to collect eggs. Nevertheless, there is a small illegal following of both of these pursuits which should be discouraged, especially where they involve rare species. Except in the case of extremely rare raptors, rehabilitation to the wild of sick, injured or orphaned

Only if raptors are understood and valued will the public accept the need for, and the cost of, their conservation. Thus, the development and dissemination of accurate information about raptors is important. To be most effective, information is best targeted at specific groups and aimed at a specific outcome. For best results, the key players should be involved. For example, if rock climbers are causing breeding failures among nesting Peregrine Falcons, then climbers, ornithologists, and local private or public land managers may need to be consulted when recommendations for the minimisation of disturbance are drawn up and circulated. Currently, information needs include the protection and management of raptors on private lands, the avoidance of untargeted poisoning of

Table 2. Official status of Australian raptors considered threatened or at risk of extinction. Federal Osprey (Australian subspecies) P. h. leucocephalus Black-breasted Buzzard Square-tailed Kite Red Goshawk White-bellied Sea-Eagle Grey Goshawk Brown Goshawk (Christmas Island subspecies) A. f. natalis Wedge-tailed Eagle (Tasmanian subspecies) A. a. fleayi

National

NSW

Vic.

Vulnerable Vulnerable Rare Vulnerable Vulnerable Vulnerable Endangered

Qld

WA

Rare Endangered ROLBE

SA

Tas.

Vulnerable Vulnerable Vulnerable

Rare Rare

Vulnerable Rare

Vulnerable Endangered

Main threats Habitat destruction Habitat destruction Habitat destruction Habitat destruction Habitat destruction Habitat destruction

Habitat destruction Vulnerable Habitat destruction and disturbance

Peregrine Falcon Grey Falcon Grass Owl (Australian subspecies) T. c. longimembris Masked Owl (southern subspecies) T. n. novaehollandiae Masked Owl (northern subspecies) T. n. kimberli Sooty Owl (Australian subspecies) T. t. tenebricosa Powerful Owl Rufous Owl (eastern subspecies) N. r. queenslandica Rufous Owl (Cape York Peninsula subspecies) N. r. meesi Barking Owl Norfolk Island Boobook N. n. undulata

Rare

OSPF Vulnerable Vulnerable Vulnerable ROLBE Vulnerable ROLBE

Vulnerable Vulnerable Vulnerable

Rare

Vulnerable Rare

Vulnerable

Rare Rare Rare

Vulnerable Rare Vulnerable Rare

Endangered Endangered

BPUIA

Christmas Island Hawk-Owl

Vulnerable Vulnerable

BPUIA

Vulnerable Rare Vulnerable Vulnerable

Persecution? Habitat destruction Habitat destruction, introduced predators Habitat destruction Habitat destruction Habitat destruction Habitat destruction Habitat destruction

Rare Vulnerable Vulnerable

Vulnerable

Habitat destruction Habitat destruction Habitat destruction; introduced species Habitat destruction

Listing according to: Federal (CESPA 1992); National; NSW (Threatened Species Conservation Act 1995); Vic. (Flora and Fauna Guarantee Act 1995); Qld (Nature Conservation Wildlife Regulation 1994); SA (National Parks and Wildlife Act 1972, amended 1991 – being updated); WA (Wildlife Conservation Notice 1997); Tas. (Threatened Species Protection Act 1995). There are no listings of threatened fauna in the Northern Territory. ROLBE – Rare or Likely to Become Extinct; BPUIA – Birds Protection under International Agreement; OSPF – Other Specially Protected Fauna. 30

raptors during pest control programs, and the assessment of raptor predation on livestock and nondestructive methods for its control. Injured raptors unable to be rehabilitated to the wild are often suitable for display at raptor education talks to school and other groups, and arouse great interest among children and teachers alike. 24 Wildlife parks and zoos are also sources of information for the public, and can enhance raptors’ image and promote legitimate conservation issues. Enough basic information is known about most Australian species, and about raptors in general, to allow intelligent decisions to be made about their conservation and management. Nevertheless, the status, ecology and conservation needs of the threatened Grey Falcon, Square-tailed Kite, Grass Owl and, perhaps, Barking Owl, warrant special research attention. Little is known of raptor ecology in northern Australia. Issues such as the effectiveness of conservation measures, the relationship between management techniques and population and community dynamics, and other ecological factors, are still little understood. Finally, there is a need for taxonomic research, blending molecular genetics and traditional techniques,25, 26 to ensure that conservation efforts are not misdirected.

CONSERVATION INITIATIVES Since 1971 all Australian raptors have been protected by legislation. However, Western Australia does not provide full protection to the Wedge-tailed Eagle and Brown Goshawk. Each State has an independent wildlife authority responsible for regional matters.

A Federal authority (Environment Australia) deals with island territories, and national and international affairs.27 Except between registered wildlife and zoological parks, there is no legal trade in birds of prey. In Australia, conservation of raptor populations has been confined largely to giving all raptors legal protection and to preserving tracts of land for the benefit of all their inhabitants – in national parks, state reserves and the like. Preservation of large tracts of land from the pervasive influence of humans remains the most effective way to conserve many species, although active management will become more essential in the future as human pressure increases. Well-managed private land has great conservation value. Increasingly, private land managers and community groups are undertaking conservation action. Initiatives such as Land for Wildlife, run in Victoria for landholders willing to preserve native habitats, and Landcare, Bushcare, Coast Care and Greening Australia, must be applauded and fostered. Several States have a system for convenanting land, which allows owners to incorporate conservation conditions into the title of their property. Large corporations also have an important role to play in habitat preservation, but have mainly confined their efforts to reducing the environmental impact of their activities and to restoring damaged areas. The Australasian Raptor Association and/or Birds Australia can offer advice on bird-related management and local land-use planning issues. In Tasmania, guidelines based on research have been formulated to minimise the effect of logging on Grey Goshawk and Wedge-tailed Eagle nesting habitats.28, 29 Buffer zones, the limiting of

I N G S PA N

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Few raptors nest on the ground. Grass Owls, like Swamp Harriers, nest in long grass and are susceptible to introduced predators, nest destruction by harvesters, and loss of nest sites to land reclamation. Photo by David Hollands

xii




ACTION PLAN

The Norfolk Island Boobook was reduced to one bird before action was taken, and now exists only as a hybrid subspecies, managed in the wild through the provision of nest boxes. Further support is needed for the raptors of Australia’s island territories. Photo by John Hicks

disturbance to the non-breeding season, and enhanced streamside reserves in core habitat are among the recommendations. Co-operation between researchers, conservation agencies and the forest industry continues to do much towards mitigating the impact of timber harvesting on large forest owls. Management of individual pairs of raptors, for their preservation, has been attempted. For example, nest boxes and platforms have been erected. Such measures are local in effect, but can generate positive publicity, co-operation and goodwill. Peregrine Falcons nest on spectacular cliffs that are also much favoured by rock climbers, nature lovers and sightseers. The risk of disturbance to resident falcon pairs has led to closure of some cliffs to the public, at least during the falcons’ breeding season. Nature trails and lookouts have been shifted or located to cause minimal disturbance to these excitable birds. Recently, attempts have been made to save telegraph poles as a means of conserving raptors. For example, on the Nullarbor Plain telegraph poles are among the few safe nesting places, as well as being favoured perches and roosts. However, the poles are now redundant and are being removed. Telstra has agreed to leave and secure every fifth pole, but other corporations have proved to be less sympathetic. Management of raptors that are harassing livestock, aviary birds or threatened species has been attempted on a small scale. Wildlife authorities allow the removal and relocation of individual ‘problem’ raptors, but rarely issue permits for their destruction.

This Action Plan has been developed for government agencies, land managers and the community, as a guide to raptor conservation issues in Australia. The list of recommended actions is not necessarily in order of priority, nor is it exhaustive. The Action Plan is underpinned by the following: • Ensure that the principles of ecologically sustainable development (ESD), particularly the management of total grazing pressure, and bio-diversity conservation are vigorously applied. • Encourage the retention, rehabilitation and long-term management of native vegetation communities, including dead trees. Avoid the destruction of wetlands. • Encourage ecologically sensitive management of fire, both in the case of wildfire and where fire is applied as a land management technique. • Employ integrated, strategic pest management practices. Thoroughly assess perceived problems, aim for a reduction in damage rather than in pest numbers, promote the use of non-chemical pest control strategies and, where the use of pesticides is necessary, use non-persistent, targeted products and techniques. • Facilitate more frequent updating and greater uniformity among the various international, Federal and local bodies in the identification and categorisation of threatened species, and expedite implementation of co-operative actions for their protection. • Ensure that legislation protecting wildlife in each State and Territory is consistent and that exploitative use of raptors, such as for falconry, remains illegal within the region. • Identify important raptor areas and expand the reserve system to ensure adequate protection. • Improve awareness of raptor conservation issues throughout the community. What can Federal and State agencies do? 1. Develop agricultural practices codes and forest practices codes in co-operation with industry within each State and Territory (where applicable). This includes the negotiation of property management agreements, whole farm plans, regional plans and the like, and adherence to the principles of ESD, for the benefit of all biota, including raptors. 2. Standardise existing legislation for the protection of native vegetation, and expedite its introduction in all States. 3. Develop financial incentives and other initiatives for private land managers that

4.

5.

6.

7.

8.

promote nature conservation in land management. Landowners should be rewarded for environmentally sound management initiatives such as preserving belts of woodland, revegetating, etc. (e.g. a subsidy to assist fencing-off a sensitive wetland area). Incentives, such as taxation deductions, for practices leading to the destruction of natural habitat should be abolished. States without conservation covenants should introduce such legislation. Expand the Comprehensive, Adequate and Representative (CAR) reserve system, as is now applied with the Regional Forest Agreements, to include all vegetation communities in each State and Territory. Particular attention should be given to the creation of more large reserves in the semi-arid and arid zones, tropical savannas, and temperate and tropical woodlands. Carry out regular, systematic monitoring of raptor populations, particularly those considered at risk, using standardised methods. Integrate this with the development of a system of user-friendly, affordable databases on wildlife distribution, numbers and habitats, easily exchanged with and interpreted by all levels of government and the public. The Birds Australia New Atlas of Australian Birds, BOP Watch and monitoring of RCD impact on raptors are examples, but would benefit from greater standardisation. Establish a ‘Raptor Research and Management Zone (RRMZ) Register’ and a ‘Raptor Research Requirements Register’ (RRRR). RRMZs can be reserved or non-reserved areas. Their primary role would be to focus research on local raptor ecology and the impact of land management practices. To be effective RRMZs should be established in a wide variety of bio-regions and, together, include all raptor species. Areas for consideration could include: Strezlecki Creek, (SA); Riverina Murray (Vic.); Darling Downs (Qld); and the various wintering areas mentioned in the main text. All States and Territories would nominate areas for inclusion in the RRMZ Register and research needs for the RRRR. Provide realistic advice on identifying, assessing and managing stock/pet predation by raptors. Promote the application of integrated, strategic pest control measures for raptors, and the use of non-destructive solutions. In conjunction with industry, improve the use of pesticides, herbicides and other chemical agents to reduce or avoid direct or indirect impacts on raptors.

Priorities include: development of environmentally-sensitive, national integrated pest management plans for major pests, and State-based actions for more localised pest problems; dissemination of associated educational material; and research on integrated management of pest damage to sugar and grain crops. 9. Encourage/promote the installation of underground or bundled cabling in areas of high collision risk for raptors and of electrocution mitigation hardware in problem areas. 10. Continue to support conservation of raptors on Australia’s island territories. 11. Encourage conservation of raptors in countries within the Australasian region. Papua New Guinea, Indonesia and some Pacific Island nations face significant conservation problems, particularly in relation to forestry and other land-use practices. Through co-operative activities the Australian Government can contribute to research and conservation initiatives in the region. What can local government do? 1. Develop and reward integrated grazing, agricultural, fire and pest management practices by local land owners and managers that maximise retention or improvement of vegetation communities and their component wildlife.

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Pacific Baza pair with frog at the nest. Mainly insectivorous, they also eat small lizards, small birds and – unusually for raptors – small fruits such as figs. Where Bazas feed in urban areas they may be susceptible to poisoning by insecticides. Photo by Lindsay Cupper

xiv


Several raptor species thrive in the suburbs, a few even taking to the inner city. In Melbourne, Peregrine Falcons have been observed hunting pigeons and insects under the city lights, and nesting on buildings high above the city streets. Photo by Victor Hurley


2. Create minimal impact residential zoning for important raptor habitats. Consider clumped housing instead of broadacre housing in rural residential areas. This means fewer physical hazards (e.g. roads, fences, wires, power poles) and greater areas of undisturbed habitat for shy species (e.g. eagles and harriers). Develop long-term plans to improve or reconstruct ‘green belt zones’. 5. Consider more than the legislative minimum. Many Australians enjoy the closeness of wildlife (e.g. ospreys nesting on suburban poles, peregrines on buildings). Environmentally sensitive policies and enlightened leadership at the local level will improve biodiversity conservation. 3. Obtain databases (and regularly update) on local biodiversity, raptor hot-spots, threatened species and threatening processes.


What can land owners and managers do? 1. Be pro-active in introducing elements of an agricultural practices code or whole farm plan. Working examples and peer pressure are powerful tools. 2. Control introduced pests using integrated management systems that avoid or minimise non-target effects. 3. Deal with perceived problem raptors strategically. Seek expert advice (e.g. from conservation agencies, Birds Australia or the Australasian Raptor Association). Thoroughly assess the problem (is the raptor the real culprit?, where and when is the problem happening? etc.) and apply non-destructive, long-term solutions that focus on alleviating the damage. 4. Disseminate information on successful, environmentally friendly farm management practices and useful conservation inventions (e.g. rafts to stop birds drowning in water troughs, efficient nest boxes etc.). 5. Offer positive criticism to government agencies. Let them know what you need to be ecologically constructive and offer practical, on-site advice. 6. Record nesting raptors on your farm plan and manage for their conservation. This is especially useful on very large properties or when there is a new manager/owner. Seek advice on better management for wildlife. 7. Place covenants over important places for raptor conservation. Advice and other help is often available from

Table 3. Conservation priorities for threatened or near-threatened (priority) raptors in Australia, other than preservation of habitat which is essential for all species. Species

NSW

Osprey Letter-winged Kite Square-tailed Kite Black-breasted Buzzard Red Goshawk Whistling Kite White-bellied Sea-Eagle Brown Goshawk Grey Goshawk Wedge-tailed Eagle Black Falcon Grey Falcon Peregrine Falcon Sooty Owl Masked Owl

RP

Grass Owl Powerful Owl Rufous Owl Barking Owl New Zealand Morepork Christmas Island Hawk-Owl

TR1 TR1 TR1 TR2

Vic.

Tas.

SA

WA

NT

Qld

TR1 TR1 TR1 RP

TR2 TR2 TR2 TR1

Island Terr.

TR1 TR1

TR2 TR1

TR1 RP

TR RP

RP RP1 RP RP

TR1? TR1 TR1 RP

TR1 RP RP RP (East RP Division), TR (Central & West Division) TR RP RP

RP

TR2 TR1

TR1 TR2 TR1

TR2

TR1

TR1 TR

TR

RP

TR2

TR2 TR1 TR1 TR2 RP RP

TR=targeted research to identify key conservation areas and requirements for development of a management plan: 1 highest priority; 2 second-highest priority. RP =Recovery or Management Plan in place or in preparation; RP=Recovery or Management Plan needed. 1 Christmas Island subspecies.

government agencies, Birds Australia and other organisations. 8. Consider ecotourism as an alternative or addition to traditional farm enterprises. For example, guide parties of birdwatchers, run nature walks from bed and breakfast accommodation, organise workshops on ecologically sensitive management practices. What can the community do? 1. Programs such as Landcare, Bushcare, Land for Wildlife and Coastcare can support raptor conservation. Bird enthusiasts are encouraged to provide local input into these programs and to seek advice and assistance from Birds Australia to develop project proposals. 2. Make yourself available to help conservation agencies, NGOs and researchers in their work. This can improve the effectiveness of research while providing participants with exciting opportunities. 3. Offer an educational service to schools and community groups to promote raptor conservation. Resources from museums, conservation agencies and licensed raptor rehabilitators can be used to support educational activities. 4. Inform local government and conservation agencies of location of raptor ‘hot spots’, such as eagle nests, and advise them of impending raptor conservation problems. Authorities are sometimes unaware of the location or importance of such sites and often it is too late to protect once development commences. Dr Penny Olsen is a Senior Research Fellow at the Australian National University. Formerly with CSIRO, she has studied birds of prey for more than 20 years

Acknowledgements Nick Mooney and Mark Holdsworth proposed this Conservation Statement and they, Stephen Debus, David Baker-Gabb, Tom Aumann and Ian Falkenberg contributed to its development. Mike Braysher commented helpfully on the Action Statements. Peter Copley (SA), David Rounsevell (Qld), Allan Burbidge (WA) and Peter Dostine (NT) provided information on the legal status of threatened raptors in their respective States, Jo Hess gave advice on powerlines, and Helen Neeve supplied information on RCD.

Edited by Stephanie Haygarth and Merrilyn Julian; layout and production by P.A.G.E. Pty Ltd; printing by Buscombe Vicprint Ltd.

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As predators at the top of food chains, raptors are particularly susceptible to secondary poisoning. This Rufous Owl is dying from the effects of brodifacoum poison, used to control the Cane Rat in the sugar industry. Further research is needed on the impact of rodenticides on raptors. Photo by John Young

A Wedge-tailed Eagle lies paralysed after hitting overhead wires between pylons; it never recovered. Collisions are a common cause of raptor mortality, particularly for fast-flying species, which collide with wires, windows or motor vehicles Photo by Nicholas Birks

REFERENCES AUSTRALIA S RAPTORS DIURNAL BIRDS OF PREY AND OWLS

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