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Tree Martin (Petrochelidon nigricans)

The Tree Martin is a small, migratory Australian swallow that breeds in tree hollows, creek banks and some artificial structures. Colonies and large night roosts can concentrate many birds near clearing and construction sites, so active nests, hollow-bearing trees and occupied roost trees need careful checking and protection. It is listed as least concern in Australia, but in Queensland it is treated as a colonial breeder, and tampering with a breeding place requires the higher risk colonial breeder management pathway.

Conservation status

Queensland, Nature Conservation Act 1992: Colonial breeder. Least concern in Queensland, but it breeds in colonies, so tampering with a breeding place needs a high risk species management program rather than the low risk program.

Migration and breeding season

Tree Martins breed in Australia mainly from July to January, with nesting most common from August to December. Timing varies between regions, and some nesting has been recorded in every month, so active hollows and other breeding places should be checked before clearing.

Breeding mode: Usually colonial or semi-colonial, although nests may also be isolated. Nests are often close together in the same large tree where suitable hollows are available.

Clutch size: Usually 3 to 5 eggs, with 2 to 5 also recorded.

Incubation: 14 to 16 days. Both parents incubate the eggs and feed the young.

Fledging and dependence: Not recorded. Treat occupied nests as supporting dependent young until activity has ceased and a fauna ecologist confirms the breeding place is inactive.

Nest and breeding-place sites: Usually horizontal hollows or spouts in dead branches, often high in eucalypts. Other sites include tree-trunk holes, eroded creek banks, cliffs, rock crevices, bridges, buildings, Stobie poles and artificial nest boxes.

Colony size and site fidelity: Small colonies are documented, but typical breeding-colony numbers are not recorded. Large aggregations of up to 10,000 birds are documented at Adelaide night roosts, but these are not confirmed as breeding colonies. Hollows may be reused year after year.

Breeding frequency: Often double-brooded. Birds that do not migrate may visit the nest site throughout the year.

Breeding and movement can shift between years and regions, and the presence of a colony, active nest or reused hollow should take precedence over calendar dates.

  • Southward arrival and settling in Australian breeding areas: Birds return from northern wintering areas before or during the breeding period, with exact arrival timing varying by region.
  • Breeding and nesting in Australia: Nesting has been recorded in all months, but activity is most common from August to December and breeding is generally reported from July to January.
  • Eggs, nestlings and dependent young: Eggs and young are most likely during the main nesting period, and the length of the fledging and dependence period is not recorded.
  • Non-breeding presence in northern Australia and nearby islands: Many birds move north after breeding and may winter in northern Australia, Papua New Guinea and nearby islands, with regional variation in where birds remain.
  • Northward departure from southern breeding areas: Departure is reported mainly from May to July as temperatures fall, although timing differs between locations and years.
  • Highest clearing risk: Risk is highest from August to January because colonies, eggs and dependent young may be present in hollows, banks or artificial breeding places; inspect first, retain active sites, and set a site-specific no-entry buffer around active colonies to prevent flushing and repeated disturbance.

Identification: Appearance and size

Tree Martins are small swallows with fast, twisting flight. They are most often detected by their calls, flocking behaviour and use of hollows or urban structures rather than by close views.

Adults have a glossy blue-black crown, nape and back. The rump is pale or greyish white, the wings and tail are brownish grey, and the underparts are cream to buff with fine streaking.

The forehead often has reddish-brown colouring. Males and females look similar. Young birds are duller, browner and paler.

Typical weight: About 15 g

Wingspan: About 28 cm

  • Length is about 12 to 13 cm.
  • The tail is shallowly forked and shorter than the folded wings, giving the bird a stumpy appearance when perched.
  • The pale rump is a useful feature in flight.

Identification: Calls and similar species

The call is a slightly metallic, high-pitched sound often described as “tsweet” or “tzweit”. Flocks also produce continuous twittering and squeaky chatter, particularly when settling into a roost.

Tree Martins can be confused with Fairy Martins and Welcome Swallows. The Tree Martin has a pale rump and a shallowly forked tail. Fairy Martins have a rufous head and nape, while Welcome Swallows have a more strongly forked tail.

  • Listen for repeated twittering around hollows, colonies and evening roosts.
  • Watch for rapid, twisting flight above trees, water and open ground.
  • Large flocks gathering before sunset may indicate a nearby night roost.

Identification: Field signs

A nest may be inside a hollow, crack, bank or artificial cavity, so it may not be visible from the ground. Mud may be plastered around a large entrance to reduce its size.

Look for repeated adult flights to one cavity, birds carrying grass or other nest material, begging young, and adults entering or leaving a hollow. Droppings or whitewash below an entrance can support an assessment, but are not by themselves proof of an active nest.

  • Horizontal hollows in dead branches, especially in large eucalypts.
  • Repeated entry to a cavity by paired birds or several birds.
  • Grass, leaves, feathers, straw or mud around a nest entrance.
  • Flock activity and persistent twittering near a known roost or breeding tree.

Distribution: Australian range

The Tree Martin occurs across much of Australia and is recorded in every Australian state and territory listed for the species. Distribution can be seasonal, with birds moving south to breed and north after breeding.

The species occurs from coastal areas to the arid inland and from sea level to more than 1500 m. It breeds in western and eastern Australia, including urban areas such as Adelaide and Perth.

Records and listings cover New South Wales, the Northern Territory, Queensland, South Australia, Tasmania, Victoria and Western Australia. Local abundance can vary between seasons and regions.

  • Look for the species in open woodland, farmland, wetlands, grassland and urban areas.
  • Large trees and nearby water increase the likelihood of use.
  • Tasmania supports the Tree Martin, including the form known as Petrochelidon nigricans neglecta.

Distribution: Seasonal movement

Tree Martins are migratory breeders. Many birds occur in southern areas during the warmer months, then move north as temperatures fall.

In Adelaide, large flocks are present from about January to May, with most birds leaving between May and July. Timing varies across Australia.

  • Breeding may occur from July to January, depending on region.
  • Some birds remain near breeding areas outside the main migration period.
  • Do not assume a site is unused because birds are absent during one survey period.

Distribution: Overseas range

After breeding, some Tree Martins move to northern Australia, Papua New Guinea and Indonesia. The wider non-breeding range also includes areas east of the Wallace Line and the Solomon Islands.

  • Migration can bring large numbers into urban and wetland areas.
  • A roost may be occupied seasonally even when no breeding occurs at the site.

Habitat: Woodland and open country

Tree Martins use open landscapes with suitable nest cavities and nearby insect-rich airspace. On works sites, assess both the trees and structures that provide cavities, and the surrounding areas used for flight and feeding.

Preferred habitat includes open eucalypt woodland, grassy woodland, heathy woodland and mallee. The species also uses farmland with scattered trees, grassland and suburban areas.

Large living trees and dead branches are valuable because they can contain hollows. Retain hollow-bearing trees wherever practicable, including isolated trees in cleared landscapes.

  • Large eucalypts with horizontal branches or dead limbs.
  • Open woodland edges and scattered paddock trees.
  • Mallee and other woodland with mature trees containing cavities.
  • Grassland and open areas adjoining trees.

Habitat: Wetlands and watercourses

Tree Martins are often associated with wetlands and areas near water. They forage over water and may use mud from the water's edge when building or modifying a nest.

Creek lines, eroded banks and wetland margins can provide both feeding areas and breeding cavities.

  • Wetlands, dams and saltmarshes with open airspace above them.
  • Eroded creek banks and steep soil faces.
  • Lignum, reedbeds and other wetland vegetation as surrounding foraging habitat, although the nest is usually in a cavity or bank rather than in the vegetation itself.

Habitat: Urban and modified sites

The species uses cities and suburbs when suitable cavities and open flight paths remain. It has been recorded around buildings, bridges, stobie poles, street trees and other infrastructure.

Urban sites can support substantial seasonal roosts. Inspect trees and structures before pruning, demolition, lighting changes, access works or vegetation removal.

  • Older buildings with ventilation holes or other cavities.
  • Bridges and structures with sheltered openings.
  • Street trees used for evening roosting.
  • Open areas around shopping centres, roads, waterways and construction compounds.

Foraging habitat: Diet and feeding behaviour

Tree Martins catch insects in agile flight and may feed high above the canopy or low over water and open ground. A site can remain important for feeding even when the nest or roost is outside the work footprint.

The diet consists of aerial insects, including flies, beetles, wasps, bugs and ants. Birds usually catch prey in the air, but may occasionally take food from the ground or other surfaces.

They often forage in fast, twisting flight and may feed at canopy height or higher. They can also fly low over water, pasture and open ground.

  • Look for repeated feeding flights over dams, wetlands, creek lines and grassland.
  • Watch for birds sallying from perches to catch insects.
  • Foraging flocks commonly contain 30 to 60 birds, but much larger flocks can occur.

Foraging habitat: Foraging areas around works

Retain open flight paths between hollow-bearing trees, wetlands and nearby feeding areas where practicable. Clearing, dust, lighting and tall temporary structures can alter how birds use the airspace.

Avoid treating a tree or bank as isolated habitat when birds are regularly feeding over adjoining water or open country.

  • Wetland margins and saltmarshes with insect activity.
  • Open woodland above and around mature eucalypts.
  • Pastures, grassland and cleared areas near nest trees.
  • Water bodies and creek lines used for low insect-feeding flights.

Foraging habitat: Site observations

Record the direction and height of regular flight paths, the location of feeding flocks and any link between feeding areas and cavities. Early morning and late afternoon observations can help identify repeated use, while the period before sunset is useful for locating roost approaches.

  • Note flock size and whether birds are carrying food or nest material.
  • Map regular flight lines across roads, work areas and water bodies.
  • Check nearby trees and structures if birds repeatedly leave the work area in one direction.

Breeding habitat: Natural breeding places

Tree Martins breed in pairs, small groups or semi-colonial clusters, depending on the availability of suitable cavities. Breeding places may be natural or artificial, and the same hollow can be reused in later years.

Most nests are in holes in horizontal branches, often high in eucalypts. Hollows may be in living trees, dead branches or dead trees. Other recorded sites include cracks in trunks, steep creek banks, cliffs and eroded banks.

The nest may be placed directly on rotten wood or on leaves, grass, straw, feathers and other material. Some nests are made or reinforced with mud.

  • Hollow spouts and knot holes in dead branches.
  • Horizontal hollows in mature eucalypts.
  • Holes and cracks in trunks or dead trees.
  • Vertical creek banks, cliffs and eroded soil faces.

Breeding habitat: Artificial breeding places

Tree Martins can nest in stobie pole tubing, ventilation holes in older buildings, bridges and other structures with suitable cavities. Artificial sites may be used where natural hollows are scarce.

Inspect buildings and infrastructure for cavities before demolition, sealing, repainting, maintenance or modification.

  • Steel tubing and cross-arms with a suitable entrance.
  • Ventilation holes in older brick buildings.
  • Bridges and sheltered structural openings.
  • Nest boxes designed for colonial use, where installation is part of an approved management plan.

Breeding habitat: Breeding timing and active nests

Breeding has been recorded from July to January, with nesting most common from August to December in South Australian records. Regional timing can vary, and suitable sites may be visited throughout the year in some non-migratory birds.

An active breeding place may be indicated by repeated adult entry, adults carrying material or food, nestlings calling, fresh nest material, or adults defending an entrance.

  • Clutch size is usually two to five eggs, with three to five also recorded.
  • Both parents may build the nest, incubate eggs and feed young.
  • Do not seal, relocate, prune around or disturb a cavity until its status has been checked by a suitably qualified person.
  • If an active nest is found, stop work close enough to cause disturbance and obtain project-specific ecological and regulatory advice.

Sheltering habitat: Night roosts

Tree Martins use trees and structures for night shelter as well as for breeding. Night roosts can hold far more birds than a breeding colony, and a large roost may be seasonal or separate from the breeding place.

Tree Martins roost in trees after dark. Recorded urban roosts include Callery pears and Chinese elms, including busy city streets with lights, people and nearby buildings.

Roosts may be concentrated in a few trees and can overflow into neighbouring streets or vegetation. A roost tree can therefore be important even when no nest is present.

Recorded urban roost size: More than 10,000 birds at Adelaide sites

Roost timing: Often occupied from late afternoon through the night, with seasonal use

  • Dense street trees and mature ornamental trees.
  • Trees near open flight paths and protected from direct access by predators.
  • Vegetation near shopping areas, wetlands, waterways and transport corridors.
  • Groups of trees where birds gather shortly before dark.

Sheltering habitat: Recognising a roost

Before sunset, birds may circle high above the site and then descend rapidly into the trees in a coordinated flock. Once settled, they may produce persistent chatter and become difficult to see among the foliage.

Repeated evening arrival, droppings beneath branches and large numbers leaving at dawn support a roost assessment.

  • Observe the site before sunset and again shortly after first light.
  • Record the trees used, the approach direction and the approximate flock size.
  • Check nearby trees because birds may shift between trees or occupy overflow roosts.
  • Avoid bright lighting, tree pruning and noisy works during the settling period where practicable.

Sheltering habitat: Breeding places versus roosts

A night roost is not necessarily a breeding colony. Breeding places are usually cavities, banks or structural openings, while roosts are commonly in the foliage of trees.

Both types of site can occur near a work area and should be mapped separately.

  • Do not remove a roost tree solely because no nest is visible.
  • Do not assume a tree used for roosting is safe to prune during the breeding season.
  • Assess roost use, breeding use, access routes and nearby feeding habitat together.

Colonies and breeding places: What a colony can look like

The Tree Martin is a colonial or semi-colonial breeder, although nests can also be isolated. Colonies need special care because one tree, bank or structure can contain several nests and represent a substantial part of the local breeding population.

A colony may consist of several nests in hollows close together in one large tree or in a group of nearby trees. Where suitable cavities are scarce, nests may be more scattered.

Colonies can also occur along banks, cliffs or structures with multiple cavities. The birds may be conspicuous in the air but the nests themselves can be hidden inside cavities.

  • Several adults using one tree or a small group of trees.
  • Repeated entry to multiple hollows or openings.
  • Nest material or mud around several entrances.
  • Flock activity around a shared breeding area, especially in the morning and late afternoon.

Colonies and breeding places: Known site types

Look for colonies in large hollow-bearing trees, especially eucalypts, as well as eroded creek banks, cliffs and buildings. Bridges and stobie pole tubing can also provide suitable cavities.

Wetland trees, riverbanks and islands may be used where they offer suitable hollows and protection, but the species is not restricted to these settings.

  • Mature eucalypts with closely spaced hollows.
  • Dead branches, hollow spouts and knot holes.
  • Steep creek banks, cliffs and eroded banks.
  • Bridges, older buildings, stobie poles and other structures with cavities.

Colonies and breeding places: Fidelity and colony protection

The same hollow may be reused in later years. A site can therefore remain important even when birds are not present during a single inspection.

There is no reliable species-specific colony size or disturbance distance for all sites. Use the observed nest distribution, flight paths, vegetation, terrain and work method to set a site-specific exclusion area around active nests and colonies.

  • Keep clearing, demolition and noisy works outside the local nesting period where practicable.
  • Establish a clearly marked buffer around active breeding places before machinery enters the area.
  • Prevent workers, vehicles, lighting and temporary structures from concentrating disturbance at colony entrances.
  • Have a fauna spotter-catcher inspect hollow-bearing trees and other breeding features immediately before relevant works.

Colonies and breeding places: Queensland regulatory consideration

In Queensland, the Tree Martin is treated as a least concern colonial breeder. Tampering with its breeding place requires the higher risk species management program pathway for colonial breeders, rather than the low risk pathway used for other least concern animals.

Confirm the applicable Queensland approval and management requirements before clearing, sealing, relocating or modifying a breeding place.

  • Plan works around active colonies and breeding places.
  • Keep records of colony location, nest activity, inspection dates and mitigation measures.
  • Escalate any proposed disturbance to an active breeding place for ecological and regulatory review.

Threats: Loss of hollow-bearing trees

Tree Martins are least concern nationally, but local breeding populations can be affected when hollow-bearing trees, colonies or large roosts are removed or disturbed. Construction planning should address direct habitat loss, disturbance and hazards around both natural and artificial sites.

Removal of mature eucalypts, dead branches and standing dead trees reduces the cavities available for breeding. Hollow formation takes many years, so replacement planting does not provide an immediate substitute.

Retain large hollow-bearing trees and connected woodland wherever practicable. If a tree must be removed, inspect it for active and inactive breeding places and follow the approved fauna management process.

  • Flag hollow-bearing trees before clearing.
  • Check dead limbs, hollow spouts and knot holes from the ground and, where safe, by qualified personnel.
  • Avoid pruning branches that contain or lead to active hollows.
  • Protect retained trees from machinery, root damage, soil compaction and accidental impact.

Threats: Disturbance to colonies and active nests

Noise, vibration, access and sudden activity can cause adults to leave a breeding place or alter feeding behaviour. Disturbance risk is highest when machinery operates close to active entrances or when access blocks the birds' flight path.

Keep works outside the nesting period where practicable. Where this cannot be achieved, use a site-specific buffer and staged works based on the colony layout and the advice of the fauna spotter-catcher or ecologist.

  • Stop and reassess if adults repeatedly flush from a cavity or fail to return.
  • Do not seal or relocate an active nest without the required approval and specialist direction.
  • Use a fauna spotter-catcher during clearing and grubbing where breeding habitat is present.
  • Inspect cavities immediately before clearing if they were not safely inspected earlier.

Threats: Loss or disturbance of roosts

Removing a small group of occupied roost trees can displace thousands of birds. Evening disturbance, pruning, bright lighting and access changes can also affect roost use.

Map occupied trees and the approach and departure routes. Schedule noisy work outside the evening settling period where practicable, and retain alternative connected trees.

  • Survey before sunset to identify roost trees and flock movements.
  • Avoid pruning or removing occupied roost trees during the roosting season unless assessed and approved.
  • Manage lighting to avoid directing strong light into roost foliage or flight paths.
  • Check nearby streets and vegetation for overflow roosting.

Threats: Infrastructure and operational hazards

Tree Martins may collide with reflective glass, shopfronts, catenary wires and other structures, particularly where large flocks enter urban roosts. Netting can also entangle birds if it is poorly designed, damaged or not installed for wildlife exclusion.

Construction compounds, temporary fencing, cranes and new lighting can create additional hazards near established flight paths.

  • Identify reflective glazing and large open entries near roosts.
  • Use bird-safe treatments where glass is part of the approved design response.
  • Do not install loose, damaged or unsuitable netting where birds can contact it.
  • Inspect temporary structures and wires near regular flock routes, especially before seasonal roost formation.

Survey methodology: 1. Desktop assessment

Tree Martins are small, fast flying and often colonial. Surveys should cover both breeding places and large night roosts, because a roosting aggregation may contain many birds but may not be a breeding colony.

Map hollow-bearing trees, mature eucalypts, dead branches, creek banks, eroded banks, cliffs, bridges, buildings and other structures that could contain nest sites.

Review records for breeding colonies, night roosts, large flocks and seasonal use. Check whether works could affect nearby wetlands, open water, woodland, farmland or urban trees used for foraging or roosting.

Treat known or suspected colonies and large roosts as sites requiring additional assessment. A colony can contain a large share of the local population.

  • Check aerial imagery and recent vegetation clearing information.
  • Speak with landholders, local councils, park staff and nearby residents about repeated evening flocks or nesting activity.
  • Identify hollow-bearing trees that may be retained, removed, pruned or affected by machinery access.

Survey methodology: 2. Field detection

Search mature trees, hollow branches, dead limbs, creek banks, cliffs, bridges, buildings and artificial nest sites. Look for birds entering hollows, carrying grass or mud, adults feeding young, fresh droppings below an opening, nest material and repeated calling.

Watch open airspace above woodland, wetlands, water and grassland. Tree Martins catch flying insects in swift, twisting flight and may be seen feeding at canopy height, higher above trees or low over water.

Check likely night roosts shortly before dark. Large flocks may gather overhead and descend rapidly into trees. Do not assume a roost is a breeding site unless nesting activity is confirmed.

  • Use quiet observation from a position that does not cause birds to flush.
  • Record calls, flight paths, nest entrances and the trees or structures used.
  • Inspect possible hollows from the ground first. Use elevated inspection only where authorised and safe.

Survey methodology: 3. Timing and conditions

Give priority to surveys during the local breeding period, generally August to December, with some records extending to January. Survey before works begin and repeat the check close to clearing if conditions or site use change.

Use early morning observations for nest activity and adult provisioning. Use the period before dark to locate communal roosts and assess flock size. Repeat observations where birds are present but nesting status is unclear.

Avoid relying on a single quiet visit. Tree Martins can move between foraging areas, nest sites and roosts, and migratory movements vary between regions.

  • Survey in calm, settled weather where possible.
  • Do not conduct close observations during heavy rain, strong wind or poor visibility if these conditions are likely to suppress flight activity.
  • Increase survey effort when birds repeatedly circle, alarm call, enter hollows or flush from a tree.

Survey methodology: 4. Records and interpretation

Record the location, date, time, weather, observers, survey duration and survey conditions. Map each active entrance, nest, colony, roost tree and likely flight path.

Record the number of birds using a site, while distinguishing a count of birds entering a roost from a count of birds nesting. Note whether the count is an estimate and whether birds were seen leaving or entering hollows.

Record evidence of breeding, including nest material, eggs, adults incubating, adults carrying food, young calling from a hollow and fledged young near the site.

  • Photograph entrances and site features from a safe distance.
  • Record any flushing, alarm behaviour or repeated avoidance of the site.
  • Provide records to the project ecologist and the relevant regulator where approval conditions require this.

Before habitat disturbance: 1. Avoidance, approvals and permits

Plan around the breeding cycle and retain the features that make the site useful. Because Tree Martins breed in colonies or semi-colonially, a small area of works can affect many pairs at once.

Retain active nests, hollow-bearing trees, mature trees used by a colony and trees used as a large night roost wherever practicable. Redesign access, laydown areas, lighting and plant movements before considering removal.

Have the project ecologist check whether the action could affect a matter protected under the Environment Protection and Biodiversity Conservation Act 1999. Make an EPBC referral where the Act requires it.

Obtain any state or territory approvals that apply to native animal, vegetation, hollow tree or breeding-place impacts. In Queensland, confirm the requirements under the Nature Conservation (Animals) Regulation 2020 before tampering with a Tree Martin breeding place.

  • For a Queensland least concern colonial breeder, use the required high risk species management program where the activity affects a breeding place.
  • Confirm whether a Queensland Department of Environment, Science and Innovation authority, permit or approved management program is required before work starts.
  • Keep approval conditions, maps and contact details on site.

Before habitat disturbance: 2. Pre-clearance survey and risk zoning

Complete a pre-clearance survey close to the proposed works. Recheck all hollow-bearing trees, structures and colony or roost locations immediately before clearing if the site has changed or the earlier survey is no longer current.

Classify the site as an active breeding place, inactive potential breeding place, night roost, foraging area or unsuitable feature. Treat an uncertain site conservatively until an ecologist has assessed it.

Set a written exclusion zone around every active nest, colony and roost. There is no single distance that suits every site. The ecologist should increase the zone if birds flush, alarm call, stop feeding or avoid the site.

  • Flag trees, hollows, nest entrances, roost trees and exclusion zones before plant arrives.
  • Keep machinery, vehicles, spoil, generators, lighting and personnel outside the exclusion zone.
  • Protect retained trees from root damage, compaction, pruning, vibration and accidental impact.

Before habitat disturbance: 3. Timing and work programming

Schedule clearing outside the local nesting period where practicable. Nesting is most common from August to December, and some breeding records extend into January. Confirm local timing before setting the work window.

Avoid removing a known roost tree during the period when large flocks are using it. In Adelaide, large night roosts have been recorded from January to May, with many birds moving north as temperatures fall.

Do not assume that winter is free of risk across Australia. Some birds remain near nest sites throughout the year, and breeding timing varies by region.

  • Stage works so that the colony, roost and nearby foraging habitat remain available until the project ecologist confirms that use has ceased.
  • Pause work if birds begin using a previously inactive structure or tree.
  • Use the quietest practicable equipment near retained breeding and roost sites.

Before habitat disturbance: 4. Exclusion and crew induction

Install durable signs and barrier tape around the approved exclusion zone. Mark the boundary on construction plans and plant operator maps.

Induct all workers, subcontractors and machine operators before entering the site. Explain the species, nest and roost signs, exclusion zones, stop work authority and reporting pathway.

A fauna spotter catcher or suitably qualified ecologist should brief the crew on the limits of their authority and the conditions that require work to stop.

  • Prohibit unauthorised entry into the exclusion zone.
  • Do not touch, seal, prune or remove a hollow, nest entrance or artificial nest site without approval.
  • Keep dogs, cats and recreational activity away from active colonies and roosts.

During habitat disturbance: 1. Sequential clearing

Clear in a controlled sequence and keep a qualified person close to the work face. A colony, active nest or roost must be managed as a live fauna issue, not as an ordinary vegetation or demolition task.

Clear low vegetation and non habitat areas first, then work towards the retained habitat under fauna spotter catcher supervision. Keep escape routes open and avoid trapping birds between machinery and exclusion zones.

Use staged removal where a potential nest tree cannot be retained. Stop before the tree or structure is affected and obtain project ecologist approval for the next step.

Check hollows, cracks, nest entrances and structures immediately before disturbance. Use a safe inspection method suited to the feature and do not insert hands into an occupied hollow.

  • Keep the spotter catcher visible to plant operators and maintain radio contact.
  • Remove or modify habitat only after the spotter catcher has cleared the work area.
  • Do not fell a tree towards a colony, roost or retained hollow-bearing tree.

During habitat disturbance: 2. Stop work and active breeding places

The fauna spotter catcher must have authority to stop work without delay. Stop if a Tree Martin enters a hollow, carries nesting material or food, feeds young, incubates, alarm calls repeatedly, or if an active nest, colony or roost is found.

Keep people and machinery back from the site. Do not chase, flush or repeatedly inspect the birds. Contact the project ecologist and follow the approval or management program.

An active breeding place must not be sealed, relocated, removed or disturbed unless the action is authorised and a suitable method has been approved.

  • Re-establish the exclusion zone if birds return after a short absence.
  • Maintain a quiet work area while the ecologist assesses the site.
  • Record the decision, person giving the direction, time of stoppage and conditions for recommencing.

During habitat disturbance: 3. Handling and injured animals

Only authorised and appropriately trained people may handle a Tree Martin. Workers must not catch, move, release or keep the bird.

If a bird is injured, stop nearby work and reduce noise and people. Keep the bird contained only where directed by a trained wildlife handler, using a suitable ventilated container and dark, quiet conditions.

Contact the fauna spotter catcher, project ecologist, wildlife carer or veterinarian through the project emergency pathway. Do not provide food or water unless directed by the receiving carer or veterinarian.

  • Record the location and circumstances of the injury.
  • Keep cats, dogs and unauthorised people away from the bird.
  • Report collision, entanglement, crushing, heat stress and nest loss as fauna incidents.

During habitat disturbance: 4. Colonies, roosts and records

If a colony or large roost is found, stop work that could disturb it and identify the trees, structures, flight paths and time of use. Avoid sudden noise, bright lighting and repeated vehicle movements near the site.

Record the estimated number of birds, the number of occupied entrances if known, behaviour, flight direction, disturbance response and the extent of the exclusion zone.

A roost may contain thousands of birds and may be separate from the breeding place. Manage both locations until their use and relationship are understood.

  • Use one nominated person to coordinate observations and communications.
  • Update site maps and exclusion signs before work recommences.
  • Report any breach of the exclusion zone immediately.

After habitat disturbance: 1. Post clearance checks

Finish each work area with a fauna check and a clear record of what happened. Post clearance follow up should confirm that retained habitat remains usable and that no animals or active breeding places were overlooked.

Inspect the cleared area, retained trees, structures, access tracks and exclusion boundaries after each stage. Look for injured birds, trapped animals, damaged hollows, fallen nests, newly exposed entrances and birds returning to disturbed features.

Check that no tree debris, netting, wire, pits, pipes or buildings create an entrapment risk. Remove hazards only when safe and authorised.

Where an active site was retained, revisit it after works resume and again after the next major construction stage.

  • Use the same mapped locations and photo points used during pre-clearance.
  • Check areas at a time when Tree Martins are active, including before dark where a roost is involved.
  • Escalate any new breeding or roosting activity to the project ecologist.

After habitat disturbance: 2. Reporting and compliance

Prepare a fauna report covering survey effort, breeding and roost observations, cleared habitat, retained features, incidents, animal handling, approvals and corrective actions.

Submit reports to the regulator, approval holder or principal contractor within the required timeframe. Keep records of all stop work directions and decisions to recommence.

Record whether mitigation measures were installed and maintained, including exclusion fencing, replacement nest structures and lighting controls.

  • Include maps, photographs, dates, observers, weather and bird counts.
  • List each active or potential breeding place affected and the final outcome.
  • Retain records in the project environmental management system.

After habitat disturbance: 3. Relocated or rescued animals

Confirm the release or placement details for every animal handled by an authorised carer or fauna spotter catcher. Record the outcome, release location and any follow up advice.

Do not release a bird into a new location without advice from the authorised wildlife handler and project ecologist. Release sites should provide suitable cover, open flight paths, food and distance from active hazards.

Replacement nest structures should be checked for use, overheating, pests, water entry and damage.

  • Record the identification method used for any monitored bird if applicable.
  • Check whether relocated birds return to the original site or use nearby retained habitat.
  • Report mortality, repeated injury or failure of a replacement structure.

After habitat disturbance: 4. Incident review and adaptive management

Review every collision, disturbance event, nest loss, tree failure, entanglement and exclusion breach. Identify the immediate cause and the site condition that allowed it.

Change work methods, lighting, access, barriers or timing where the review shows that birds are being flushed or injured.

Consult the regulator and approval holder if the event may breach an approval, management program or permit.

  • Discuss findings with the spotter catcher, supervisors and plant operators.
  • Update the induction and site map after each material change.
  • Continue monitoring where birds remain near the works or where the project has affected a colony or roost.

Rehabilitation actions: 1. Restore breeding habitat

Rehabilitation should restore the features Tree Martins use for nesting, feeding and shelter. Retain natural hollows wherever possible, because replacement structures do not provide all of the functions of mature trees.

Retain and protect mature eucalypts, dead branches and hollow-bearing trees during rehabilitation and future maintenance. Allow suitable trees to age and develop hollows rather than removing every dead limb.

Restore open woodland, grassland, wetland edges and creek lines near retained trees. Maintain open flight paths and insect-rich areas for aerial feeding.

Stabilise eroded creek banks only where required for safety or water quality, and assess whether the work could remove a known breeding bank before construction.

  • Use locally appropriate native plants and natural regeneration where practicable.
  • Control weeds without spraying active nest trees, occupied hollows or nearby foraging habitat.
  • Keep fallen timber and suitable dead branches where they do not create a safety hazard.

Rehabilitation actions: 2. Nest boxes and artificial nest sites

Use nest boxes only where natural hollows are limited and the project ecologist considers them suitable. Tree Martins are colonial or semi-colonial, so install several boxes or a group of artificial nest sites rather than a single isolated box where space allows.

A suitable Tree Martin box described for this species is horizontal, with an internal floor of 15 cm by 15 cm, an internal height of 10 cm and a 3 cm entrance. The entrance should be 2 to 3 cm above the floor.

Install boxes at least 2 m above ground, with open flight lines, partial shade and protection from afternoon heat, prevailing summer wind and rain. Keep the box at least 2 m from objects that could give rats access.

  • Use thick timber or another well insulated material, untreated inside and protected from heat outside.
  • Provide a projecting entrance or roof to keep rain out.
  • Mount boxes on poles, legs or buildings in a way that prevents rats and mice reaching them.
  • Use a removable back for inspection and maintenance.

Rehabilitation actions: 3. Roosts, structures and lighting

Retain established roost trees where possible. Replace a roost only after an ecologist has assessed the function of the site and the risks of moving a large flock.

Bat boxes are not a substitute for Tree Martin nest boxes. Artificial nest sites for Tree Martins should provide the entrance, dimensions, shade and open flight path suited to this species.

Manage lighting near breeding places and roosts to avoid sudden glare, direct illumination of entrances and disruption of evening arrival. Address reflective glass, open shopfronts, wires and other collision hazards near urban roosts.

  • Keep roost trees connected to open airspace and nearby foraging habitat.
  • Use bird safe glazing treatments where collision has occurred.
  • Do not net trees or structures without a wildlife safe design, approval and inspection plan.

Rehabilitation actions: 4. Water, weeds and long term monitoring

Protect wetlands, creek lines and shallow water used by flying insects. Maintain natural water regimes where possible and avoid sudden water level changes that remove feeding habitat during the breeding season.

Monitor restored sites for nest box occupation, natural hollow use, colony formation, roost use, weed invasion, pest access and heat damage. Survey during the local breeding period and before dark for roost activity.

Continue monitoring long enough to detect whether birds return, whether replacement structures are used and whether the surrounding habitat supports feeding.

  • Inspect nest boxes at least annually once established, using a qualified person and a low disturbance method.
  • Repair damaged boxes and remove pests when authorised and safe.
  • Map all restored breeding and roost features and include them in future work plans.
  • Use monitoring results to adjust planting, weed control, lighting and access management.

Sources