Indicative distribution
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas.
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The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Strepera graculina crissalis
Profile last updated:
25 Jan 2019
Description
The Lord Howe Currawong is a subspecies of the Pied Currawong, which occurs in eastern mainland Australia. The Lord Howe Currawong is a fairly large, crow-like bird, slightly bigger than an Australian Magpie (Cracticus tibicen), with a long, robust and pointed bill, and bright, golden-yellow eyes. It is glossy black with a white tip to the tail, and conspicuous white patches on the outerwings, at the base of the uppertail, and on the lower undserbody and base of the undertail. The Lord Howe Currawong differs from most other subspecies by its slightly longer and more slender bill, and smaller white patches and narrower white tail-tip.
Distribution
The Lord Howe Currawong is restricted to Lord Howe Island. It is distributed across the the island, though more widespread and more abundant in the southern mountains and northern hills. They also occur on some associated islets, including those of the Admiralty Group, off the northern tip of Lord Howe Island itself.
Habitat and ecology
- The Lord Howe Currawong occurs in lowland, hill and mountain regions of the island. It is mainly found in tall natural rainforests and palm forests, typically undisturbed, but it also occurs in cleared and settled areas, remnant patches of forest and the ecotone between cleared land and forest. The subspecies also forages in colonies of seabirds on offshore islets.
- Lord Howe Currawongs breed in rainforest and palm forest, mainly on hill-slopes and mountains, with all breeding territories including a section of stream or gully and with most nests near water.
- After breeding, in autumn and winter, Currawongs tend to disperse from higher altitudes to the lowlands, with greater numbers in lowland forests and in cleared and settled areas of the island at this time.
- Lord Howe Currawongs forage at all levels of their habitat, from the ground to the canopy, and sometimes aerially. They are omnivorous, eating a wide range of fruits, seeds, invertebrates, and small vertebrates, particularly rats and mice, and small birds, bird eggs and nestlings. Currawongs also eat fruits and seeds of some exotic plants and are implicated in the spread of such species on the island. They are the only remaining native predator of vertebrates on the island.
- Most breeding occurs in late spring and early summer (September or October to December), though there is some evidence of breeding occasionally occurring as early as July. The clutch is three eggs, though there are few records of clutch-size; in mainland Australia, clutches are of one to four eggs, usually three or four.
- Nests are usually placed high in trees and are often inaccessible. The nest is a large, rough open bowl-shape made of sticks, twigs and vines, and with a neat inner cup of fine vegetation, such as grass and palm thatch.
- Nestlings remain in the nest for about 30 days, and then stay with their parents for another 50 or so days until they are independent.
- There are few data on breeding success. In the 2005-06 breeding season, five of twelve clutches observed produced at least one fledgeling, and one pair successfully reared two broods (a total of five fledgelings). Successful broods usually consist of one or two young but, in some seasons, pairs may not rear a brood at all.
- The age at which Lord Howe Currawongs first breed is not known, nor is the life expectancy of the subspecies. However, on the mainland, individuals have been known to live for more than 20 years.
- Birds defend territories in the breeding season, with some territories defended throughout the year. Territories are usually about 6 ha in area, with some up to 10 ha, and territorial boundaries may vary with population.
- Lord Howe Currawongs occur singly, in pairs, small family groups after breeding and, in the non-breeding season, in small flocks of up to 15 birds. Their flight is distinctively undulating.
- They are also often bold and inquisitive birds, and readily adapt to the presence of humans and occupy human settlements.
Regional distribution and habitat
Click on a region below to view detailed distribution, habitat and vegetation information.
Threats
- Risk of extinction owing to its small population size. The total population of the Lord Howe Currawong is estimated to be 200 individuals (from surveys in 2005-06).
- Introduction of exotic predators or pathogens could have a significant adverse impact on the single and small population of this taxon.
- Human persecution owing to the Currawong's habit of attacking native and domestic birds, in particular predation on the iconic and endemic Lord Howe Woodhen (Gallirallus sylvestris) and the White Tern (Gygis alba); the latter, and a fairly recent coloniser of Lord Howe Island, is a favourite of residents and visitors alike. Currawongs were often shot historically and shooting still occurs occasionally.
- There is some risk of secondary or non-target poisoning of Currawongs during baiting programs for Black Rats (Rattus rattus) and House Mice (Mus musculus) as Currawongs often take poisoned rats and mice.
- The fact that the subspecies is restricted to a small isolated island, Lord Howe Island, places it at risk from stochastic and other impacts with no opportunities for natural recolonisation.
Recovery strategies
Priority actions are the specific, practical things that must be done to recover a threatened species, population or ecological
community. The Office of Environment and Heritage has identified
3 priority actions
to help recover the Pied Currawong (Lord Howe Is. subsp.) in New South Wales.
Activities to assist this species
- Ensure adequate quarantine procedures are in place to eliminate the risk of introduction of exotic predators or pathogens (Such action is required for the entire suite of endemic taxa occurring on Lord Howe Island.)
- Investigate impacts on Lord Howe Currawongs of current rodent control programs, and develop and use appropriate methodologies to ensure the species is not impacted on.
- Monitor populations to identify trends in size and health of populations, especially declines in population levels or evidence of disease.
- Encourage an appreciation of the importance of the Lord Howe Currawong as a native forest predator, and the only native predator of vertebrates in the island group. Promoting knowledge of the important role of the Lord Howe Currawong in the island's ecosystem will potentially do much to reduce human impacts and negative attitudes towards this subspecies.
- Retain native vegetation and undertake relevant revegetation and weed control, especially in lowland habitat.
- Monitor the impacts of climate change and develop strtaegies to alleviate any potential impacts.
- Evaluate the implementation of the Lord Howe Island Biodiversity Management Plan.
- Undertake further surveys and research into the ecology of the subspecies to develop adequate knowledge of the subspecies to ensure its conservation.
- Studies are needed to determine if this isolated island form should be treated as a distinct species.
Information sources
- Department of Environment and Climate Change (NSW) (2007) Lord Howe Island Biodiversity Management Plan. Department of Environment and Climate Change (NSW), Sydney.
- Department of the Environment, Water, Heritage and the Arts (2010) Strepera graculina crissalis. In: Species Profile and Threats Database.
- Fullagar, P.J. and Disney, H.J. de S. (1975) The birds of Lord Howe Island: a report on the rare and endangered species.
- Fullagar, P.J., McKean, J.L. and van Tets, G.F. (1974) Report on the birds. Environmental Survey of Lord Howe Island. A Report to the Lord Howe Island Board.
- Garnett, S.T. and Crowley, G.M. (2000) The Action Plan for Australian Birds 2000. Environment Australia, Canberra.
- Hindwood, K.A. (1940) The birds of Lord Howe Island. Emu 40:1-86.
- Hutton, I. (1991) Birds of Lord Howe Island Past and Present.
- Knight, B.J. (1987) A population survey of the Lord Howe Island Currawong.
- McAllan, I.A.W., Curtis, B.R., Hutton, I. and Cooper, R.M. (2004) The birds of the Lord Howe Island Group: a review of records. Australian Field Ornithology 21: 1-82
- McFarland, D.C. (1994) Notes on the Lord Howe Island Currawong Strepera graculina crissalis. Australian Bird Watcher 15: 310-313.
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