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Bush Stone-curlew (Burhinus grallarius)

The Bush stone-curlew is a large, nocturnal, ground-dwelling bird of open woodland, lightly timbered forest and some swamp margins across mainland Australia. It is sensitive to clearing, removal of fallen timber, foxes, cats, stock and disturbance around ground nests, so retained woodland structure and pre-clearing surveys are important on development sites.

Conservation status

New South Wales, Biodiversity Conservation Act 2016: Endangered.

Victoria, Flora and Fauna Guarantee Act 1988: Critically endangered.

Northern Territory, Territory Parks and Wildlife Conservation Act 1976: Near threatened.

Breeding season

Breeding timing varies across the mainland range. The periods below combine the June to December timing reported for Queensland, the August to February timing reported for South Australia and the July to January survey period used in New South Wales.

Seasonal timing varies across Australia. Check state requirements and local records before clearing or disturbing potential habitat.

  • Mating and laying: Breeding is reported from June to December in Queensland and from August to February in South Australia. Eggs are usually laid as a clutch of two in a ground scrape.
  • Incubation and dependent young: Incubation takes about 28 days. Chicks cannot fly until about 9 weeks old, so eggs and young may remain exposed on the ground for an extended period after laying.
  • Nocturnal movement and territory: The species feeds at night and occupies breeding territories reported as 10 to 25 ha. No seasonal migration pattern is described in the supplied documents.
  • Highest clearing risk: Clearing and disturbance are most likely to harm the species from the start of the documented breeding periods through the period when eggs and flightless young may be present. Risk is highest from August to December, but can extend from June to February depending on location.

Identification

Bush stone-curlews are large, long-legged birds with cryptic grey-brown plumage. They are often detected by their call or by a frozen, crouched bird in woodland rather than by flight.

Adults stand about 50 to 60 cm high and have long, gangly legs, knobbly knees that are actually ankles, large golden or yellow eyes and a small black bill.

The upperparts are grey-brown with dark streaking. A white forehead and eyebrows, broad dark-brown eye stripe and mottled plumage provide camouflage among grass, leaf litter and fallen timber.

The wingspan is about 82 to 105 cm. Males weigh about 670 g and females about 625 g.

Identification: Field separation

The combination of very long legs, large yellow eyes, a dark eye stripe, grey-brown streaked plumage and a small black bill is distinctive among large Australian ground birds.

The bird is mainly nocturnal. During the day it commonly crouches low, freezes or walks slowly away rather than flying when approached.

The loud, repeated wailing call, described as “wer-lo wer-lo” or “weer-lo”, is often the first indication that birds are present after dark.

Identification: Field signs

Search for a simple ground scrape containing two mottled brown and grey eggs, usually beside a fallen log or other fallen timber.

A pair or small group may be seen roosting on open ground beneath woodland, in parks or gardens, or at the timbered edge of a swampy area.

When defending eggs or chicks, adults may hiss and spread their wings. No diagnostic scat, track, eyeshine or other field sign is described in the supplied documents.

  • Listen for the repeated wailing call after dark.
  • Search around fallen logs, branches and bark for shallow ground nests.
  • Record birds that crouch or freeze instead of flushing when approached.

Distribution: National range

The species occurs across mainland Australia, but its distribution is now uneven and has contracted substantially in south-eastern Australia. The supplied documents do not provide a named national bioregion list or a current national population estimate.

Bush stone-curlews are reported from all mainland states. They occur in open forests and woodlands, including areas near watercourses or swamps, and may also use swampy paddocks, mangroves and salt marsh margins.

Queensland populations occur on the mainland and Moreton Bay islands, including around residential areas on the Redlands Coast. In south-eastern Australia, the range is now largely confined to grassy woodlands and farmland.

States and territories mentioned: Queensland, New South Wales, Victoria, South Australia, Western Australia and the Northern Territory, based on the statement that the species occurs in all mainland states

Named bioregions: Not specified in the supplied documents

Distribution: Strongholds and trend

The main Victorian and New South Wales stronghold identified in the supplied material is the border region, although birds are sparsely distributed there and continue to decline.

The species is extinct from many former sites south of the Great Dividing Range. In South Australia it has disappeared from about 90 per cent of its former mainland habitat.

Historically, groups of 50 to 100 birds were recorded. Such large flocks no longer occur in Victoria, and sightings on private properties were reported to have declined from four pairs to one pair per property over 30 years.

Historical group size: 50 to 100 birds

Reported private property trend: Decline from 4 pairs to 1 pair per property over 30 years

South Australian range contraction: About 90 per cent of former mainland habitat no longer occupied

Distribution: Project records

Most Bush stone-curlews in south-eastern Australia occur on private land. A lack of records should not be treated as evidence of absence because the species is secretive, nocturnal and well camouflaged.

For clearing and construction projects, inspect open woodland, fallen timber and grassy remnants across the site and listen after dark where habitat remains suitable.

Habitat: Habitat types

Bush stone-curlews use open, lightly timbered habitats with a sparse ground layer and abundant fallen timber. Habitat structure is important for both camouflage and predator avoidance.

Core habitat includes grassy woodlands and lightly timbered open forests. In south-eastern Australia, the species is also associated with farmland containing suitable woodland remnants.

The species may occur in swampy paddocks, mangroves and salt marshes, but it generally roosts at timbered margins in these wetter settings.

The supplied documents do not provide an elevation limit, temperature limit or rainfall limit.

Habitat: Vegetation and structure

In south-eastern Australia, preferred woodland types include buloke, gum and box woodlands with low, sparse grass or herb understorey.

Fallen logs, branches, bark and other woody debris are important. They provide camouflage and are associated with nest sites, and birds may be reluctant to nest where fallen timber has been removed.

A sparse understorey allows birds to see predators while foraging. Completely open areas without nearby timber cover are less suitable for roosting and nesting.

  • Retain fallen logs, branches, bark and other ground timber.
  • Retain grassy woodland remnants and timbered edges around swampy areas.
  • Avoid creating dense ground vegetation that removes visibility for foraging birds.
  • Keep stock away from known nests and occupied breeding areas.

Foraging habitat: Diet

Bush stone-curlews forage on the ground at night. They use open woodland and sparse grassy areas where prey can be detected and approached while the bird retains visibility of predators.

The diet includes insects, spiders, seeds and small vertebrates. Documented animal prey includes small frogs, lizards and snakes.

The supplied documents do not identify particular food plant species.

Animal prey: Insects, spiders, small frogs, lizards and snakes

Other food: Seeds

Foraging habitat: Foraging conditions

Foraging occurs on the ground at night in open forests, woodlands and grassy areas with a sparse understorey.

The species benefits from ground cover that is open enough to maintain visibility, while nearby fallen timber provides camouflage and shelter.

A specific foraging radius or distance from the roost is not provided. Reported breeding territories are 10 to 25 ha, but this should not be treated as a confirmed foraging range.

  • Survey grassy woodland remnants, sparse understorey and timbered edges as potential night foraging habitat.
  • Retain ground timber while avoiding unnecessary accumulation of dense vegetation that obstructs visibility.
  • Inspect adjoining paddocks and swamp margins where they connect to suitable woodland.

Breeding habitat: Breeding biology

Breeding occurs on the ground in simple scrapes, usually close to fallen timber. The breeding pair is territorial and both parents incubate the eggs.

Breeding season: June to December in Queensland material; August to February in South Australia

Clutch size: Usually 2 eggs

Nest form: A simple scrape or small bare patch on the ground

Incubation: About 28 days

Parental care: Both parents incubate; chicks remain unable to fly until about 9 weeks old

Age at maturity: Not provided in the supplied documents

Lifespan: More than 20 years

Breeding habitat: Nest habitat

Nests are usually beside a fallen log and may be difficult to see because the eggs and adults are well camouflaged.

Suitable breeding habitat consists of grassy woodland or lightly timbered open forest with low, sparse understorey, fallen timber and enough open ground for a scrape.

Stock can trample eggs. Foxes and cats can locate adults, eggs or chicks more easily where fallen timber has been removed.

  • Search around fallen logs and woody debris for a shallow scrape and two mottled eggs.
  • Treat occupied nests and nearby fallen timber as breeding habitat during clearing and construction.
  • Keep stock, domestic pets and construction activity away from nest sites.
  • Use daytime nest searches with flushing and dusk or nocturnal call surveys where the species is a target of the survey program.

Sheltering habitat: Day roosts and cover

The species shelters in open woodland and ground cover rather than in hollows, burrows or tree nests. Fallen timber is a key refuge and camouflage feature.

During the day, Bush stone-curlews rest crouched on the ground with the head outstretched. Roosts may be in open forests, woodlands, parks and gardens.

The birds use grey-brown plumage and fallen timber for concealment. Branches, bark and logs on the ground are therefore shelter features, not waste material to be removed.

The supplied documents do not give a standard roost diameter, log size, refuge distance or den dimension.

  • Retain fallen logs, branches and bark around mature trees and within woodland remnants.
  • Inspect areas beneath and beside ground timber before clearing or earthworks.
  • Avoid storing construction materials or placing access tracks through likely daytime roost areas.

Sheltering habitat: Shelter from predators

Fallen timber helps conceal birds and nests from foxes and cats. Removing it can expose birds and make nesting attempts less successful.

A sparse understorey allows the birds to see approaching predators while they forage and rest.

  • Retain connected patches of low, sparse understorey and ground timber.
  • Include fox and cat control in management plans where Bush stone-curlews or nests are recorded.
  • Do not clear fallen timber from around retained trees unless it is required for a demonstrated safety reason.

Threats: Clearing and fragmentation

The main documented threats are loss and fragmentation of open woodland, removal of fallen timber, predation and disturbance at ground nests. Risk is highest where clearing removes both cover and breeding substrate.

Clearing and ongoing fragmentation have caused the main decline in south-eastern Australia. At least 85 per cent of habitat was reported as cleared or fragmented in Victoria.

Removal of woodland, grassy remnants and timbered edges reduces roosting, foraging and nesting habitat. The species is now extinct from many former sites south of the Great Dividing Range.

  • Avoid clearing grassy woodland and lightly timbered remnants.
  • Retain fallen logs, branches and bark within and around retained vegetation.
  • Treat small private-land remnants as potentially important, particularly in south-eastern Australia.

Threats: Predators and stock

European red foxes are a major threat to adults, juveniles, eggs and chicks. Cats are also identified as predators, and domestic pets can kill birds.

Stock may trample eggs. Nest disturbance by people, dogs and other domestic animals can also cause breeding failure.

  • Control foxes and cats around known or potential breeding habitat.
  • Keep stock away from nests and retain predator-resistant cover around breeding sites.
  • Keep domestic cats indoors at night and dogs on leads near occupied habitat.

Threats: Fire, timber removal and construction

Fuel management burns can remove the ground cover used for foraging and shelter. Firewood collection removes logs, branches and bark that provide camouflage and nesting context.

Clearing, access tracks, machinery and night works can disturb ground-roosting or nesting birds. The supplied documents do not provide a species-specific road mortality rate or disease threat.

  • Avoid fuel reduction burning in occupied habitat during the breeding period unless the ecological effects have been assessed.
  • Do not collect firewood from Bush stone-curlew habitat.
  • Complete daytime nest searches and targeted dusk or night surveys before clearing.
  • Mark and protect any nest, distinctive call location or occupied roost identified during pre-clearing checks.

Threats: Survey and protection measures

The reviewed New South Wales forestry survey design used call playback at 500 m intervals during the breeding season, with at least 5 minutes of playback followed by 10 minutes of listening at each point. The playback was combined with a slow walk to flush birds and a nest search.

The same review recommended daytime nest searches, targeting the species in spotlight surveys and using call playback with other nocturnal bird surveys. These methods provide a useful reference for project survey design where they are appropriate to the approval and site context.

  • Use experienced fauna personnel familiar with nocturnal bird calls, cryptic ground nests and habitat assessment.
  • Survey potential habitat during the relevant breeding period, with particular attention to July to January where the New South Wales method applies.
  • Record calls, birds, nests, roosts, fallen timber and nearby predator activity, not just visible birds.

Survey methodology: 1. Daytime habitat traverse and nest search

Bush stone-curlews are nocturnal, ground-dwelling birds that can remain motionless or crouch when approached. Surveys must cover both daytime shelter and nesting habitat, and night-time activity areas.

Search potential habitat during daylight, including grassy woodland, lightly timbered open forest, woodland edges, farmland with retained trees, and areas with fallen timber.

Walk slowly through the proposed disturbance footprint and adjoining retained habitat, checking beside fallen logs, under sparse ground cover and around tree bases.

Search for birds, pairs, chicks, eggs, scrapes, feathers, faeces, tracks and repeated roosting locations.

Include a slow walk with any call playback survey because birds may freeze or walk slowly instead of flying when disturbed.

Breeding period reported in Queensland: June to December

Breeding period reported in South Australia: August to February

Typical clutch size: Two eggs

  • Give particular attention to nests beside fallen logs, because nests are simple ground scrapes and can be difficult to see.
  • Record the location and condition of every nest, roost, pair, flock, chick and suitable fallen-timber feature.
  • Treat a suspected nest or breeding territory as occupied until a suitably experienced ecologist has assessed it.

Survey methodology: 2. Call playback and listening

In New South Wales forest survey guidance, conduct playback at 500 metre intervals through potential habitat during the breeding season, July to January.

At each station, play the call for at least 5 minutes, followed by 10 minutes of listening.

Combine playback with a slow walk to flush birds and with nest searches.

Conduct playback at dusk, and consider repeating the survey on more than one suitable night where detection is important.

Playback spacing in the cited NSW forestry guidance: 500 metres

Playback duration at each station: At least 5 minutes

Listening period after playback: 10 minutes

Specified NSW breeding-season survey period: July to January

  • Avoid windy or rainy conditions where they would reduce audibility or bird activity.
  • Record all auditory responses, including the characteristic repeated wailing call, and map the direction and estimated location of responding birds.
  • Use playback only where it is permitted and where the surveyor considers disturbance acceptable during the breeding period.

Survey methodology: 3. Spotlighting and night searches

Undertake night searches in potential habitat because the species feeds after dark and may be detected walking, calling or foraging on the ground.

Use a suitably experienced surveyor and a slow, quiet transect through the proposed works area and retained adjoining habitat.

Include spotlighting as a target method where the project may affect suitable habitat, as recommended by the NSW expert review.

Survey in suitable weather, with low wind and no rain where practicable, and record start and finish times, route, weather, moon conditions and effort.

Typical standing height: 50 to 60 centimetres

Reported territory size in Queensland: 10 to 25 hectares

  • Scan open ground, fallen timber, woodland edges and sparse grassy areas rather than relying only on canopy observations.
  • Do not approach closely enough to cause a bird to flush, because the species commonly freezes or crouches when threatened.
  • Record each bird separately where possible, including behaviour, direction of travel and whether it is part of a pair or flock.

Survey methodology: Minimum effort and reporting

  • Survey the entire disturbance footprint and all immediately adjoining habitat that could be used for roosting, nesting or escape cover.
  • Use daytime nest and habitat searches, dusk call playback where appropriate, and night searches or spotlighting where suitable habitat is present.
  • Increase coverage when dense fallen timber, low visibility, recent records, repeated calls or evidence of nesting indicates a higher likelihood of occupancy.
  • Have all surveyors record the method, date, time, effort, weather, coordinates, habitat condition, detection type and photographs where safe.
  • Submit confirmed and probable records, including nil results where required, to the relevant state wildlife database or threatened-species records system.
  • Check the current state survey and record requirements before relying on the older NSW forestry guidance.

Before habitat disturbance: Avoid and minimise

Plan the works around the bird's use of ground cover, fallen timber and open woodland. Avoid removing the features that provide camouflage, nesting cover and foraging habitat.

Retain grassy woodland and lightly timbered open forest with a low, sparse understorey wherever practicable.

Retain fallen logs, branches, bark and other woody debris, especially beside trees and in areas where birds or nests have been recorded.

Avoid clearing connected woodland remnants and retain movement routes between occupied or suitable areas.

Keep stock, domestic animals and construction traffic away from known or suspected nests, eggs and chicks.

Do not collect firewood or remove fallen timber from retained habitat.

  • Do not use a generic cleared-ground treatment for this species, because open ground with nearby fallen timber may be nesting or foraging habitat.
  • Design exclusion areas around confirmed nests and active breeding sites with advice from the project ecologist and relevant authority.
  • Use project-specific buffers based on the approved conditions, the nest location, machinery reach, noise and traffic risk, rather than applying an unsupported standard distance.

Before habitat disturbance: Approvals and work planning

Confirm the current Commonwealth and state conservation status before works begin, and determine whether an EPBC Act referral or state approval, permit or species management authorisation is required.

Check the relevant state controls for clearing, wildlife handling, nest disturbance, animal relocation and work near threatened fauna.

Schedule high-risk clearing outside the locally applicable breeding period where practicable, noting that published breeding periods vary between June to December and August to February.

Stage clearing so retained habitat, escape routes and adjoining cover remain available while the fauna spotter catcher checks each work area.

  • Prepare a fauna management plan that identifies survey methods, exclusion areas, stop-work triggers, handling authority, injury response, reporting and contact details.
  • Brief machinery operators, supervisors and subcontractors on the species' appearance, behaviour and distinctive night call.
  • Confirm how records and incidents will be reported to the relevant state agency and wildlife database.

Before habitat disturbance: Pre-clearance and site preparation

Complete a pre-clearance inspection immediately before works, even where an earlier ecological survey found no birds or nests.

Mark all nests, roosts, pairs, chicks, occupied areas and retained fallen-timber features before machinery enters the site.

Install exclusion fencing where it can keep machinery, vehicles, people, stock and pets away from occupied habitat without blocking the birds' access to retained cover.

Remove only those habitat features authorised for removal, and retain logs and woody debris within protected areas where safe.

  • Inspect the footprint and a suitable adjoining area at dawn or dusk when recent calls or sightings indicate occupancy.
  • Do not rely on the bird flying away as evidence that the area is clear.
  • Obtain ecologist approval before removing an exclusion fence or changing a marked work zone.

During habitat disturbance: Daily controls and machinery interface

Use a controlled, staged clearing process. The fauna spotter catcher must be able to stop machinery before a bird, nest or shelter feature is damaged.

Inspect the active work area at the start of each shift and after breaks, equipment changes or movement into a new clearing zone.

Keep machinery within the approved clearing limits and use a slow, staged approach to retained trees, logs and dense ground cover.

Position the fauna spotter catcher where the operator can see and hear clear stop and proceed signals.

Maintain exclusion fencing, signs and marked nest or habitat zones throughout the work.

  • Stop work immediately when the fauna spotter catcher gives a stop signal or when a bird, nest, egg, chick or unexpected habitat feature is found.
  • Do not chase, corner, catch or move a bird merely because it is walking through the work area.
  • Keep workers and machinery quiet and still while the fauna spotter catcher assesses the animal.

During habitat disturbance: Fauna handling and habitat features

Only a person authorised under the relevant state requirements and approved project fauna management plan may capture, handle or relocate a bird.

Allow an uninjured bird to move to nearby retained habitat where it can do so safely, unless the authorised fauna handler determines that capture is necessary.

Handle eggs, chicks and adults only when required to prevent immediate harm, and use methods approved for the project and state jurisdiction.

Inspect ground habitat before moving logs, branches, rocks, stockpiles or machinery that could conceal a bird or nest.

Do not burn, chip or remove fallen timber in a retained exclusion area unless the approved plan specifically allows it.

  • Treat every ground scrape containing eggs or chicks as an active nest and keep machinery out until the ecologist or relevant authority provides direction.
  • Do not relocate a nest, eggs or chicks unless the relevant authority and an appropriately authorised wildlife professional approve the action.
  • Take an injured bird to an approved wildlife carer or veterinarian through the project's wildlife response contact, and record the transfer.

During habitat disturbance: Stop-work triggers and records

Stop work for any confirmed or suspected bush stone-curlew, nest, egg, chick, injured bird or previously unrecorded occupied habitat within the work area.

Stop work if exclusion fencing is damaged, a marked boundary is displaced, or machinery enters a protected zone.

Record the date, time, coordinates, observer, activity, animal condition, photographs, action taken, relocation or treatment details and the person who authorised the decision.

  • Notify the site supervisor, project ecologist and fauna spotter catcher immediately after a stop-work event.
  • Do not resume work until the fauna spotter catcher and project ecologist confirm that the approved controls are in place.
  • Report any injury, death, nest damage, unauthorised handling or clearing breach through the project's incident and regulatory reporting process.
  • Submit verified sightings and incident records to the relevant state wildlife database where required.

After habitat disturbance: Post-clearance checks

Check the completed area for missed birds and damaged nests, then keep retained habitat protected. Post-clearance actions should confirm that the project has not removed the features needed for shelter and breeding.

Inspect the cleared edge, retained woodland, fallen-timber piles and adjoining habitat after each clearing stage.

Repeat checks at dusk or at night where the pre-clearance survey detected calls, pairs or regular activity.

Check that all marked nests and exclusion zones remain intact and that no eggs, chicks or injured birds have been left in the work area.

Remove temporary fencing only after the project ecologist confirms that the area is safe and the approved work stage is complete.

  • Record any new call, bird, nest, chick, carcass, injury or change in habitat condition.
  • Investigate any sudden disappearance of birds from an occupied area when clearing or construction has occurred nearby.

After habitat disturbance: Monitoring and reporting

Monitor retained habitat where the project approval or fauna management plan requires it, using repeat daytime searches, call listening and night observations suited to the original survey design.

Compare post-work records with pre-clearance records for birds, pairs, nests, calls, fallen timber and habitat condition.

Maintain predator, pet, stock and public access controls around known breeding areas for the period specified by the approval or management plan.

  • Provide the landholder, project manager and relevant regulator with the required survey, incident and monitoring reports.
  • Submit confirmed records to the relevant state wildlife database and retain spatial data, photographs and field sheets with the project records.
  • Apply any approved offset, restoration or compensatory habitat measure required for residual impacts.

Rehabilitation actions: Habitat restoration

Rehabilitation should recreate open woodland with a low, visible understorey and retain woody debris on the ground. Planting alone is not enough if fallen timber and predator controls are absent.

Retain or re-establish open woodland and grassy areas with a low, sparse understorey suitable for walking, foraging and predator detection.

Use locally appropriate native woodland species, including the buloke, gum or box communities identified as habitat in south-eastern Australia.

Reinstate fallen logs, branches and bark in safe locations near retained or replanted trees, because the species uses woody debris for camouflage and nesting cover.

Protect remnant trees and allow future fallen timber to remain rather than removing it for firewood or site tidiness.

Restore connected patches between retained woodland where clearing has fragmented suitable habitat.

  • Do not create dense shrub planting across the whole rehabilitation area, because the species needs open sightlines and sparse ground cover.
  • Keep restored grass below 15 centimetres where this is consistent with the local habitat and project requirements.
  • Designate no-firewood-removal areas within rehabilitated habitat.

Rehabilitation actions: Predator, stock and fire management

Control foxes and manage domestic cats and dogs near occupied or restored habitat in accordance with approved state and project programs.

Fence rehabilitation areas where stock could trample nests, eggs or chicks, while retaining safe access for the birds.

Use weed control to maintain open grassy ground and prevent dense cover from replacing the preferred understorey.

Plan fire management so burns do not remove the ground cover, fallen timber and shelter required by the species.

  • Do not undertake hazard-reduction burning or fuel removal in occupied habitat without a species-specific assessment and approval.
  • Coordinate predator control across adjoining properties where practicable, because animals can move between project and retained areas.
  • Inspect fences and predator-control measures after storms, fire or maintenance works.

Rehabilitation actions: Monitoring and success measures

Monitor rehabilitation during the approved period using repeat daytime searches, dusk call listening and night observations.

Measure survival of planted woodland species, grass height, retention of logs and woody debris, weed cover, predator activity and evidence of stock access.

Use records of birds, pairs, calls, nests and chicks to assess whether the restored area is being used.

  • Set success measures before works begin, including retained or restored habitat extent, condition of fallen timber, absence of uncontrolled stock access and documented bush stone-curlew use.
  • Investigate failure where rehabilitation becomes densely vegetated, loses fallen timber, has persistent predator activity or shows no expected use despite suitable habitat.
  • Continue maintenance and monitoring until the approval conditions and agreed ecological performance measures are met.

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