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Western False Pipistrelle (Falsistrellus mackenziei)

The Western False Pipistrelle is a small insectivorous microbat of south western Western Australia. It uses mature forest, tree hollows and fallen hollow logs, so clearing and tree removal can affect roosts and feeding habitat even when bats are not seen. It is not listed as threatened in Australia, but is listed as a Priority 4 taxon in Western Australia and is treated as a colonial breeder for Queensland management purposes.

Conservation status

Breeding behaviour, All states and territories: Colonial breeder. Breeds in colonies or shared roosts, so one breeding place can hold a large share of the local population.

Breeding season

Species-specific breeding timing for the Western False Pipistrelle is poorly documented. For this Western Australian microbat, plan for breeding and maternity roost use during the warmer months, broadly spring to late summer, with some variation between years and sites.

Breeding mode: Colonial breeder. Females may gather in maternity roosts or shared breeding colonies.

Typical litter size: Usually one pup per female per year for microbats. This has not been confirmed specifically for the Western False Pipistrelle.

Gestation: Not recorded.

Fledging or weaning: Not recorded. Dependent young are expected during the warmer-month breeding period.

Breeding frequency: Usually one breeding attempt per year for microbats. Species-specific confirmation is not available.

Breeding and roost sites: Old-tree hollows, branches, stumps and fallen hollow logs are recorded roost sites. Other microbat roosts can include fissures, loose bark, caves, mines, culverts, bridges and buildings.

Recognising an active breeding place: Confirmation is strongest when pregnant or lactating females, pups or a maternity colony are recorded. Acoustic detectors, emergence watches, harp traps or mist nets, and inspection of suitable hollows with an endoscope or pole camera can assist assessment.

Breeding timing may shift between years and regions, particularly with temperature, rainfall, food availability and local roost conditions; confirm suspected colonies before clearing and use staged or soft felling where hollow-bearing trees cannot be retained.

  • Breeding activity and maternity roost use: Treat September to February as the likely breeding and maternity-roost period for planning purposes.
  • Dependent pups in maternity roosts: Young may be present in roosts during the warmer months, so avoid disturbing suspected maternity sites during this period.
  • Colonial roost use: Roosting colonies are recorded at 5 to 30 bats, and breeding colonies may contain a substantial share of the local population.
  • Night-time foraging and emergence activity: The species is a fast, direct, high-flying insectivore, with detection generally easier when bats are active in warmer months.
  • Winter torpor or reduced activity: Microbats commonly reduce activity and enter torpor in winter, although the timing and extent are not documented specifically for this species.
  • Highest clearing risk: Clearing or felling hollow-bearing trees during September to February has the greatest potential to harm maternity colonies, pups and dependent young.

Identification: Appearance and flight

The Western False Pipistrelle is a fast, direct flying microbat. It is most likely to be detected by its ultrasonic calls or by inspection of suitable roost trees, rather than by close visual observation.

This is a small insectivorous bat. It is a fast, direct, high flier and has been captured about 8 m above the ground in forest.

No reliable field description is available for separating it from similar small forest bats by eye. Treat an unidentified forest microbat as potentially significant until acoustic or capture records are assessed by a suitably experienced person.

Identification: Calls and similar species

The species uses echolocation to navigate and locate flying insects. Species identification from calls can be difficult, so recordings should be analysed with suitable reference calls and, where necessary, checked by a bat ecologist.

Other small forest bats, including Vespadelus and Chalinolobus species, may occur in the same landscapes. Do not rely on flight height, call presence or general appearance alone for identification.

  • Use Anabat, Song Meter or similar ultrasonic detectors for presence surveys.
  • Use harp traps or supervised mist nets only under appropriate animal ethics, licensing and welfare procedures.

Identification: Field signs

Look for bats emerging at dusk from hollow-bearing trees, fallen hollow logs, bridges, culverts, buildings and other enclosed structures. A single observation does not establish the location of a maternity roost.

Droppings, urine staining, odour and smooth, worn entrances can support a roost assessment, but signs may be faint or absent. Bats do not build nests, and whitewash is more commonly associated with birds than with bat roosts.

  • Repeated bat activity at one tree or structure.
  • Ultrasonic calls recorded near a hollow, fissure or enclosed roost.
  • Droppings below a hollow, crevice or roost entrance.
  • Bats entering or leaving a feature during an emergence watch.

Distribution: Australian range

The Western False Pipistrelle is endemic to south western Western Australia. On a work site, the likelihood of occurrence is greatest where mature forest or woodland remains connected to larger areas of suitable habitat.

The species is restricted to the south western corner of Western Australia. It is associated with the jarrah forest and the high rainfall forests of the South West.

It has not been seen in the northern part of its former range, including north of Collie in the jarrah forest and north of Mandurah on the Swan Coastal Plain. Recent records include areas near Stratham, Australind and Bedfordale.

  • Mapped state: Western Australia.
  • Known regional associations: jarrah forest, karri forest, marri and tuart forest, and Banksia woodland.
  • The species is not known from other Australian states or territories.

Distribution: How to apply the range information

Desktop records should be checked against current databases before clearing. A lack of recent records on a particular property does not exclude use of suitable mature forest or connected woodland.

The species has been recorded in tall open forest and riparian habitat. Retain habitat connections where practicable, especially between mature trees and larger forest remnants.

Distribution: Survey planning

Plan acoustic surveys before clearing where suitable habitat is present. Detectors are most useful when positioned near likely foraging areas, movement corridors and hollow-bearing trees.

A targeted assessment may also need emergence watches and direct inspection of trees or structures proposed for removal. Survey effort should reflect the size and complexity of the site and the likelihood of roosting habitat.

Habitat: Vegetation communities

The species is strongly associated with mature forest and woodland. It can occur in working landscapes where suitable trees, fallen logs, riparian vegetation and links to larger habitat areas remain.

Look for wet sclerophyll forest and high rainfall jarrah dry sclerophyll forest. Karri, jarrah, marri and tuart are important associated eucalypts.

The species has also been recorded in Banksia woodland, including woodland on the Swan Coastal Plain. Tall mature stands are more suitable than young regrowth with few hollows.

  • Tall mature jarrah, karri, marri and tuart forest.
  • Wet sclerophyll forest with a developed canopy and understorey.
  • Banksia woodland connected to larger habitat areas.
  • Riparian forest and tall open forest.

Habitat: Site features to retain

During pre clearing inspections, map old trees, hollow-bearing trees, large branches, stumps and fallen hollow logs. These features may provide roosting opportunities even when no bat is present at the time of inspection.

Maintain links between mature trees, riparian zones and surrounding forest where possible. Avoid treating isolated trees as having no value simply because the surrounding vegetation is disturbed.

  • Hollow-bearing eucalypts and other old trees.
  • Fallen hollow logs and large hollow branches.
  • Riparian strips, forest edges and movement corridors.
  • Continuous woodland leading to larger forest remnants.

Habitat: Construction interface

Use the habitat map to guide access tracks, laydown areas, vegetation clearing and night works. Keep machinery and lighting away from retained hollow-bearing trees where practicable.

If clearing is unavoidable, inspect trees and logs before disturbance. A fauna spotter catcher should be present for any approved removal of potential roost features.

Foraging habitat: Foraging areas

The Western False Pipistrelle hunts flying insects in forest airspace. It is a high flier that can use the space between the canopy and understorey, as well as open tracks and edges within mature forest.

Look for tall forest with a layered canopy and understorey, forest tracks, riparian vegetation and edges that provide insect activity. Flowering jarrah and marri can attract insects and may increase bat activity nearby.

The species has been recorded in tall open forest and riparian habitat. Suitable foraging habitat may remain usable even when a roost is in a nearby tree, log or structure outside the immediate work area.

  • Spaces between canopy and understorey.
  • Forest tracks and gaps through mature vegetation.
  • Riparian zones and damp forest edges.
  • Areas near flowering jarrah or marri and other insect rich vegetation.

Foraging habitat: Survey methods

Use ultrasonic detectors for several suitable nights where practicable. Record the location, date, weather, detector settings and habitat context for each deployment.

Acoustic data provide evidence of activity and presence. They do not, by themselves, confirm a maternity roost or provide a population estimate.

  • Position detectors near likely flight paths, foraging areas and movement corridors.
  • Use emergence watches at trees or structures with suspected roost activity.
  • Use harp traps or mist nets only when the method is justified, licensed and supervised.

Foraging habitat: Managing foraging habitat

Retain mature canopy, understorey structure and riparian vegetation around works where practicable. Limit unnecessary night lighting near retained forest and potential roosts.

Avoid creating barriers between roost trees and nearby feeding areas. Schedule noisy or high impact works away from confirmed roost entrances where a site specific ecologist recommends this.

Breeding habitat: Likely maternity habitat

Species specific breeding information for the Western False Pipistrelle is limited. For site management, assume that a suitable shared roost may become a maternity roost until surveys show otherwise.

Potential maternity habitat includes hollow-bearing trees, hollow branches, stumps and fallen hollow logs in mature forest. Other microbats may also raise young in fissures, loose bark, caves, mines, culverts, bridges and buildings.

A maternity roost is a place where young are raised. Any roost containing pups, or used by pregnant or lactating females, should be managed as a breeding place.

  • Old trees with internal hollows and protected entrances.
  • Large branches, stumps and fallen hollow logs.
  • Crevices, loose bark and other enclosed tree features.
  • Culverts, bridges, buildings, caves and mines where bats are present.

Breeding habitat: Breeding timing

Most Australian microbats give birth to one pup a year in the warmer months, usually from spring to late summer. Use this as general planning guidance, not as a species specific breeding calendar for the Western False Pipistrelle.

Avoid disturbing a suspected maternity roost during the period when young may be unable to fly. A suitably experienced bat ecologist should set the site specific timing and controls.

Breeding habitat: Confirming a maternity roost

Look for pregnant or lactating females and dependent pups during authorised capture surveys. Emergence watches can show repeated use, but they do not alone confirm that young are being raised.

An endoscope or pole camera may help inspect a hollow without felling the tree. Inspection should be undertaken by trained personnel and should not injure bats or damage the roost.

  • Repeated emergence from the same feature.
  • Pups visible within a hollow or enclosed roost.
  • Pregnant or lactating females recorded at the feature.
  • Adult bats carrying or returning to a roost after emergence.

Sheltering habitat: Tree and ground roosts

Roosting habitat is concentrated in mature trees and other enclosed features. Retain and protect these features wherever possible, including where they occur outside the main area of vegetation clearing.

Known roost features include hollows in old trees, branches and stumps. Fallen hollow logs are also used as roosting habitat.

Inspect the whole tree, not only the trunk. Hollows may occur in limbs, broken tops, branch junctions and the base of a tree. Treat large fallen logs as potential roosts until checked.

  • Old hollow-bearing trees.
  • Hollow branches and broken limbs.
  • Stumps with internal hollows.
  • Fallen hollow logs.

Sheltering habitat: Other microbat roosts

Microbats may shelter in fissures, loose bark, caves, mines, culverts, bridges and buildings. These features should be included in the site inspection where they occur.

A structure can be used as a night roost, temporary shelter or maternity roost. The management response should be based on evidence of use and the risk of harm during the proposed works.

Sheltering habitat: Pre clearing checks and tree removal

Inspect potential roost trees before clearing, using a pole camera or endoscope where safe and practicable. An emergence watch can help identify active entrances that are difficult to inspect from the ground.

Where removal is approved, use a two stage or soft felling approach. Lower limbs and sections slowly, pause to allow animals to escape, and have a fauna spotter catcher inspect felled material and hollows.

  • Mark and retain suitable trees where practicable.
  • Fence or otherwise protect retained roost trees from machinery and soil disturbance.
  • Check hollow sections, branches and logs after felling.
  • Provide a safe release point if a bat is found during works.

Sheltering habitat: Exclusion and supplementary roosts

Exclusion devices should only be installed after the site has been assessed and outside the maternity season. They must allow bats to leave but prevent re entry, and should not be used when flightless young may remain inside.

Bat boxes can supplement natural roosts, but they do not replace mature hollow-bearing trees. Boxes should be installed and monitored under advice from a bat ecologist, with attention to heat, placement and protection from disturbance.

Colonies and breeding places: What a colony or maternity roost looks like

The Western False Pipistrelle roosts in colonies of about 5 to 30 bats. As a colonial breeder, one maternity roost can contain a substantial part of the local breeding group, so disturbance at one site can have effects beyond the individual bats seen during a site visit.

A colony may use one hollow, several hollows in the same tree, a group of nearby trees, or another enclosed structure. Bats may be hidden during the day and leave together or in a steady stream around dusk.

A maternity roost is a breeding place where females gather and young are raised. The entrance may look ordinary from the ground, with little external evidence of use.

Typical roosting colony: About 5 to 30 bats.

General microbat breeding period: Warmer months, usually spring to late summer.

  • Several bats emerging from one hollow or structure.
  • Repeated use of the same tree or feature on consecutive evenings.
  • Pups or lactating females recorded inside or near the roost.
  • Accumulated droppings below an entrance or within an accessible hollow.

Colonies and breeding places: Site fidelity and active roosts

Individual bats may use more than one roost and may return to suitable roosts over time. Do not assume that a tree is unused because no bats are seen during one daytime inspection.

An active roost is best demonstrated by repeated emergence activity, acoustic detections concentrated at the feature, direct inspection, or capture evidence. Keep the feature under observation if results are inconclusive.

  • Conduct emergence watches from before sunset until activity has finished.
  • Repeat observations when the risk of disturbance is high or the first result is uncertain.
  • Combine acoustic monitoring with tree inspection and, where authorised, harp trapping or mist netting.

Colonies and breeding places: Why colonies need special care

Disturbing a maternity roost can separate mothers from pups, cause abandonment, or expose bats to heat, cold and predators. Removing one hollow-bearing tree may affect many bats at once.

Queensland transport guidance treats microbats as colonial breeders because they form colonies during the breeding season. In Queensland, tampering with the breeding place of a least concern colonial breeder requires a high risk species management program under the Nature Conservation (Animals) Regulation 2020, rather than the low risk program used for other least concern animals.

  • Stop work if a colony, pups or a suspected maternity roost is found.
  • Keep people, machinery and unnecessary lighting away from the entrance.
  • Obtain project specific advice before exclusion, removal or disturbance.
  • Record the feature, evidence, actions and follow up monitoring.

Colonies and breeding places: Practical controls on works sites

Where a potential roost tree must be removed, use staged or soft felling under fauna spotter catcher supervision. Retain nearby hollow trees and fallen logs where practicable, and provide replacement roost features only as a supplement.

Do not seal, cut or fell a suspected active maternity roost without an approved method and suitable timing. Exclusion devices must be checked to ensure no bats or dependent young remain inside.

  • Map all potential roost features before clearing.
  • Use a two stage or soft felling method for approved tree removal.
  • Schedule exclusion outside the maternity season.
  • Use bat boxes only as supplementary habitat, not as a substitute for natural hollows.

Threats: Clearing and loss of roost trees

The main work site risks are the loss of hollow-bearing trees, loss of mature forest and disturbance at occupied roosts. Threats can arise from direct clearing, access works, fire management and changes to surrounding habitat.

Removing old trees, hollow branches, stumps and fallen hollow logs can remove current or future roosts. A tree does not need to contain a visible bat to have value as a potential roost.

Retain hollow-bearing trees and logs within the site wherever practicable. Protect retained trees from machinery, stockpiling, trenching and changes to ground levels.

  • Avoid clearing mature trees where design changes can retain them.
  • Mark no go areas around retained trees and roost features.
  • Inspect all approved removal trees before works begin.
  • Check felled material for bats and other fauna.

Threats: Loss and fragmentation of feeding habitat

Logging, burning, agriculture, housing and other clearing can reduce mature forest and feeding areas. Fragmentation may also remove flight paths between roosts and feeding habitat.

Retain canopy links, riparian vegetation, forest edges and connected woodland. Keep new access routes and hardstand areas as compact as practicable.

  • Maintain links to larger forest remnants.
  • Retain tall mature forest and riparian vegetation.
  • Avoid unnecessary clearing along forest tracks and movement corridors.
  • Revegetate disturbed edges with suitable local vegetation where required.

Threats: Competition and habitat degradation

European Honey Bees and Rainbow Lorikeets can compete for tree hollows. Fire, logging and repeated disturbance can also reduce the supply of mature trees and future hollows.

Do not remove occupied or potential hollows for convenience. Where competition or pest occupation is suspected, seek advice before intervention because the hollow may still be used by bats.

  • Record hollow competition during tree inspections.
  • Retain a range of hollow-bearing trees and future hollow trees.
  • Manage fire and vegetation disturbance in line with site approvals and ecological advice.

Threats: Disturbance during construction

Noise, vibration, lighting, dust and repeated access near a roost can cause bats to avoid a feature or leave at an unsafe time. Night lighting can also alter movement and insect activity around retained habitat.

Use exclusion zones and a site specific timing plan around confirmed or suspected roosts. Stop work and contact the fauna spotter catcher or project ecologist if bats, pups or a colony are found.

  • Minimise lighting directed at roost entrances and retained forest.
  • Keep machinery and workers away from active roosts.
  • Avoid exclusion during the maternity period.
  • Document any unexpected bat interaction and the response taken.

Survey methodology: 1. Desktop assessment

Western False Pipistrelles are small insectivorous microbats that can be difficult to detect by sight. Use several methods together, especially where mature forest, old trees, hollows, fallen hollow logs or riparian habitat will be disturbed.

Map mature Jarrah, Karri, Marri and Tuart forest, Banksia woodland, riparian vegetation, old trees, hollow-bearing trees, fallen hollow logs and nearby water.

Review fauna databases, previous reports, aerial imagery and local records. Consider records from the wider connected woodland, not only the project boundary.

Identify likely flight paths, forest tracks, canopy gaps, dams, lakes and movement corridors. The species has been recorded in tall open forest and riparian habitat.

Known roosting habitat: Old tree hollows, branches, stumps and fallen hollow logs

Reported roosting groups: 5 to 30 bats

Distribution: South-west Western Australia, including Jarrah, Karri, Marri and Tuart forests

  • Record known or potential roost trees and hollow logs on construction drawings.
  • Check whether the project could affect a colony, maternity roost, breeding place or a concentration of hollow-bearing trees.
  • Use a suitably experienced bat ecologist where the project may remove or disturb roost habitat.

Survey methodology: 2. Acoustic survey

Deploy Anabat, Song Meter or comparable ultrasonic detectors in likely foraging areas, movement corridors, riparian zones and near hollow-bearing trees.

Survey during the warmer, active part of the year where practicable. Avoid relying on winter data alone because bats may enter torpor and activity is lower.

Use repeated nights under suitable weather conditions. A published project survey used three detectors for four consecutive nights, with 8 to 12 hours of recording per night. Treat this as an example of effort, not a universal minimum.

Have calls analysed by a suitably experienced bat call analyst. Call identification can be difficult, so report confidence and retain the original recordings.

Recorded survey example: Three systematic sites, four consecutive nights, 8 to 12 continuous hours per night

Useful survey period: Warmer months, when bats are most active

  • Avoid strong wind, heavy rain and unusually cold conditions.
  • Record detector location, height, orientation, settings, dates, start and finish times, weather, habitat and nearby lighting.
  • Report passes, call quality, species identification confidence and any evidence of repeated activity at a roost.

Survey methodology: 3. Roost and colony investigation

Inspect hollow-bearing trees from the ground, then use an endoscope or pole camera where safe and authorised. Do not put hands into hollows or disturb concealed animals.

Conduct emergence watches at suspected roosts from before sunset until activity has finished. Use infrared or red-filtered lighting where appropriate and keep observers quiet and away from the hollow entrance.

Use harp traps or supervised mist nets only under the relevant authority and with an experienced bat handler. Mist nets require constant supervision. Harp traps and nets can help confirm species, sex, reproductive condition and movements.

Pregnant or lactating females, pups, repeated emergence, concentrated bat calls or dependent young confirm that a roost is being used for breeding. Treat a roost where young are raised as a breeding place.

Maternity confirmation: Pregnant or lactating females, or pups and dependent young

Colony description: A shared roost or maternity site used by several bats; reported Western False Pipistrelle roosting groups contain 5 to 30 bats

  • Record the tree or structure identifier, species, condition, hollow entrance, height, aspect, evidence of use, emergence numbers and photographs.
  • Do not seal, block, fumigate or fell a suspected roost until the ecologist has assessed it.
  • Assume that a suitable hollow may be reused. Plan for repeated use unless survey evidence supports another conclusion.

Survey methodology: 4. Survey reporting

Prepare a map of all detections, potential roosts, breeding places, flight paths and proposed clearing limits.

Describe survey limitations clearly, including weather, access, detector failures, call identification confidence and any areas not inspected.

Provide a practical recommendation for each roost tree or structure, including retain, exclusion, staged removal, further survey or specialist inspection.

  • Keep original recordings, photographs, field sheets, trap records and weather data.
  • Record both positive and negative results. A negative detector result does not prove that a hollow is unused.
  • Escalate unexpected breeding activity or a colony record before works continue.

Before habitat disturbance: 1. Avoidance, approvals and permits

Plan around roost protection rather than relying on rescue after clearing starts. Western False Pipistrelles depend on mature forest and hollow-bearing trees, and microbat maternity roosts are protected breeding places where the relevant legislation applies.

Retain mature forest, hollow-bearing trees, fallen hollow logs, connected woodland and riparian vegetation wherever practicable. Redesign access, laydown areas and services to avoid roost trees.

Confirm the species status and approval pathway for the project location. Western False Pipistrelle is recorded in Western Australia as a DBCA Priority 4 species and is not listed as threatened under the national listings described for this profile.

Consider whether an EPBC Act referral is required for impacts on any nationally listed species or protected matter. Obtain all relevant state or territory approvals before clearing.

For Queensland projects, treat the species as a least concern colonial breeder where the Queensland framework applies. Tampering with its breeding place requires the high risk species management program pathway, not the low risk pathway used for other least concern animals. Obtain the required Queensland SMP and any fauna handling authority before work.

Queensland breeding place pathway: High risk SMP for a least concern colonial breeder where the Queensland framework applies

Western Australian conservation status: DBCA Priority 4

  • Check local clearing, wildlife, threatened species and animal welfare requirements.
  • Use appropriately authorised fauna spotter catchers and wildlife rehabilitators.
  • Do not assume that a general clearing approval authorises disturbance to a breeding place.

Before habitat disturbance: 2. Colonies and breeding places

A colony or maternity roost may be in a tree hollow, fissure, loose bark, cave, mine, culvert, bridge, building or another enclosed structure. For this species, old tree hollows, branches, stumps and fallen hollow logs are documented roosting features.

Reported roosting groups contain 5 to 30 bats, but a maternity site may contain dependent young that are not visible from outside. Treat any shared roost as potentially significant to the local population.

Microbats form colonies during the breeding season. Most give birth to one pup in the warmer months, usually from spring to late summer. Species-specific breeding dates and maternity colony sizes are poorly known, so avoid disturbance during this period unless a qualified ecologist and the approval pathway support it.

Assume repeated use of suitable roosts. A tree with bat guano, staining, noise, hair, scratch marks, an odour, repeated emergence or concentrated calls may be active. Confirm use with inspection and survey rather than relying on one sign.

Likely breeding period for microbats: Warmer months, usually spring to late summer

Typical litter size for many microbats: One pup per year

  • Map and label every suspected colony, maternity roost and breeding place.
  • Set a site-specific no-go area around an active roost, based on the structure, flight path, machinery risk and advice from the project ecologist and regulator.
  • Do not remove a roost tree simply because no bat is visible during a daytime check.
  • Stop and reassess if pregnant or lactating females, pups or a group of bats is found.

Before habitat disturbance: 3. Pre-clearance survey and exclusion

Complete a pre-clearance inspection shortly before works. Recheck all marked trees, buildings, bridges, culverts, mines and other enclosed structures that could provide shelter.

Use acoustic monitoring, emergence watches and internal inspection where safe. Use harp traps or mist nets only when necessary, under authority and with experienced personnel.

If a non-breeding roost must be vacated, install a suitable one-way exclusion device outside the maternity season. Confirm that no bats remain before removal. Do not exclude a maternity roost while young are dependent.

For hollow-bearing trees, use two-stage or soft felling. Remove non-hollow limbs first where safe, pause, then lower the hollow section carefully. Keep the section stable and provide an escape opportunity under expert direction.

  • Schedule high-risk tree works outside the maternity period where practicable.
  • Leave retained trees, hollow logs and exclusion devices undisturbed until the ecologist releases them.
  • Do not use smoke, poison, expanding foam, netting or unapproved sealants to clear bats.
  • Install bat boxes only as supplementary habitat. They do not replace an active maternity roost without a specific design and monitoring plan.

Before habitat disturbance: 4. Induction and work controls

Brief the clearing crew, supervisors, operators and spotter catchers before work starts. Show them photographs of the species, likely roost features, exclusion devices and stop-work triggers.

Mark no-go areas, retained trees, access routes and staged-felling zones on the ground and plans.

Nominate one fauna spotter catcher with authority to stop work. Ensure the person can contact the ecologist, site supervisor, regulator and wildlife carer.

  • Tell all workers not to touch bats, enter hollows or remove exclusion devices.
  • Keep machinery, lighting and people away from roost entrances and flight paths where directed.
  • Carry suitable containers, gloves, cloth bags and a quiet holding area for authorised fauna handlers.
  • Record the pre-start briefing, attendees, date, controls and questions raised.

During habitat disturbance: 1. Sequential clearing and soft felling

Clear slowly and in stages. Give the spotter catcher control to pause the operation whenever a bat, roost, colony, pup or unexpected hollow is found.

Clear non-habitat areas first, then work towards retained vegetation and identified roost trees. Keep machinery outside marked exclusion areas until the spotter catcher releases them.

Use two-stage or soft felling for hollow-bearing trees where removal is approved. Lower limbs and hollow sections rather than allowing them to fall uncontrolled.

Avoid clearing at night when bats may be leaving or returning to roosts, unless the approved method specifically requires night work and lighting is managed.

  • Inspect each tree immediately before cutting.
  • Pause between stages to allow animals to leave under supervision.
  • Keep hollow logs and felled sections intact if they are to be retained as habitat.
  • Stop work if the tree condition differs from the pre-clearance assessment.

During habitat disturbance: 2. Animal handling and active breeding places

Only authorised, trained fauna personnel may handle bats. Do not attempt capture or release without the required authority and equipment.

If an active breeding place, colony, maternity roost, pup or dependent young is found, stop work in the affected area. Protect the roost and its access route, then contact the project ecologist and relevant regulator.

Do not relocate a maternity colony or separate a pup from its mother. Do not install an exclusion device until the breeding use has ended and the method has been approved.

If a bat is found in a tree section, keep the section quiet, shaded and stable. Follow the ecologist's instructions for inspection, release or transfer to a licensed wildlife rehabilitator.

  • Establish a temporary no-go area around the find.
  • Record the location, structure, number of bats, age class, reproductive condition and photographs where safe.
  • Resume only when the ecologist confirms the control measures and approval conditions are satisfied.
  • Treat a roost used by young as a breeding place.

During habitat disturbance: 3. Injured or distressed animals

Keep people, dogs and machinery away from the animal. Do not give food or water and do not expose it to heat, rain or direct sun.

Use a clean, secure, ventilated container only if an authorised handler directs the action. Keep the container dark and quiet.

Contact a licensed wildlife rehabilitator or veterinarian promptly. Record the handover and any advice received.

  • Use gloves and avoid contact with bat saliva or bites.
  • If a person is bitten or scratched, wash the wound immediately and seek urgent medical advice.
  • Do not release an injured bat at the work site without professional advice.
  • Keep the animal separate from other fauna.

During habitat disturbance: 4. Stop-work records

Record every stop-work event, including the trigger, location, time, weather, structure, animal condition and action taken.

Photograph the roost or tree only when this can be done without causing disturbance. Retain call files and inspection records.

Update the clearing map and daily fauna register before work resumes.

  • Record the name and authority of the handler.
  • Record all animals captured, released, transferred or found dead.
  • Notify the site supervisor and project ecologist on the same shift.
  • Report incidents to the regulator when required by the approval, permit or SMP.

After habitat disturbance: 1. Post-clearance checks

Completion of clearing does not end the risk. Check the work area, verify that no animals remain in felled material or structures, and close out each fauna event with clear records.

Inspect felled hollow sections, debris piles, buildings, culverts and retained trees after each clearing stage. Check shaded crevices and hollow entrances from a safe position.

Complete a final walkover of the disturbed area with the spotter catcher. Check that no bats, pups, injured animals or displaced roost structures remain.

Keep retained hollow logs and habitat features in the positions specified by the rehabilitation or clearing plan.

  • Do not bury, burn or chip hollow-bearing material until it has been inspected and released.
  • Check exclusion devices and temporary barriers for damage.
  • Record the date, area cleared, trees removed, habitat retained and search findings.
  • Arrange a further emergence check if unexpected bat activity continues.

After habitat disturbance: 2. Reporting and compliance

Prepare a fauna clearance report that links field records to the approved clearing footprint and conditions.

Include maps, photographs, detector data, emergence observations, handling records, breeding-place findings, incidents and corrective actions.

Report injured, dead, trapped or relocated bats and any disturbance to an active breeding place in accordance with the permit, SMP, approval and regulator requirements.

  • Provide the report to the project manager, ecologist and relevant authority within the required timeframe.
  • Record whether each mitigation measure was completed, changed or not used.
  • Keep records with the project environmental management system.
  • Update the risk assessment if a colony or maternity roost was found.

After habitat disturbance: 3. Relocated animals and follow-up

Use release sites selected by the ecologist, with suitable cover, connected vegetation and low immediate construction risk. Do not release bats into an occupied roost without assessment.

Confirm the receiving site and timing with the wildlife rehabilitator or fauna ecologist. Monitor released animals where the approval or management plan requires it.

Review whether the animal returned to the area, used a retained roost or required further care.

  • Record release location, date, time, species, sex, condition and handler.
  • Keep rehabilitated animals under professional care until they are fit for release.
  • Do not describe a relocation as successful solely because the animal was released.
  • Report mortality or failure to establish as an incident and review the method.

After habitat disturbance: 4. Incident review

Review every unexpected roost, colony, injury, mortality, escape or breeding-place disturbance with the clearing supervisor, spotter catcher and ecologist.

Identify whether the cause was missed habitat, inadequate induction, poor timing, equipment failure or a change in site conditions.

Change the work method before the next clearing stage.

  • Record corrective actions and the person responsible.
  • Retrain operators where a control was not understood or followed.
  • Use lessons from the project to improve future hollow-tree and microbat procedures.
  • Escalate repeated incidents to the project manager and regulator where required.

Rehabilitation actions: 1. Restore roosting habitat

Rehabilitation should restore mature-forest structure and retain the features that bats use for roosting and foraging. Artificial roosts can support recovery, but they do not replace established hollow-bearing trees or an active maternity roost.

Retain living mature trees, standing dead trees and fallen hollow logs wherever safe. Protect retained trees from soil compaction, root damage, fire, pruning and unnecessary lighting.

Replace removed habitat with locally appropriate native plantings that will develop canopy, understorey and connected flight paths. Protect regrowth from grazing, fire and repeat clearing.

Place salvaged hollow logs in stable, shaded locations where they will not be crushed or moved during later works.

  • Use local provenance species suited to the site and surrounding Jarrah, Karri, Marri, Tuart or Banksia woodland.
  • Link restored vegetation to nearby mature forest, riparian habitat and movement corridors.
  • Control weeds before planting and during establishment.
  • Use fencing or markers to protect rehabilitation areas from vehicles.

Rehabilitation actions: 2. Bat boxes and artificial roosts

Use bat boxes or other artificial roost structures only after an ecologist confirms that they suit the local species and habitat. Design, placement and maintenance should reflect the target microbat community.

Install structures before or during habitat works where practicable, but treat them as supplementary. A box does not compensate for the loss of a mature hollow or confirm that a colony has been replaced.

Consider salvaged hollow sections or purpose-built roost structures where an approved plan identifies a suitable need. Keep entrances clear and protect structures from vandalism, excessive heat and artificial light.

  • Use several suitable structures where the ecologist recommends them, rather than relying on one box.
  • Record design, materials, location, height, aspect, installation date and inspection access.
  • Do not open, move or clean an occupied box without specialist advice.
  • Do not use artificial structures as a reason to remove an active maternity roost.

Rehabilitation actions: 3. Food, water and lighting

Restore native canopy and understorey that support flying insects. Maintain vegetation along forest edges, tracks and riparian areas where bats may forage.

Protect dams, lakes and drainage features from sediment, chemical contamination and unnecessary disturbance. Keep water edges connected to vegetation where practicable.

Reduce artificial light near retained trees, roost entrances, water and flight paths. Use the lowest practical intensity, shield fittings and direct light away from habitat.

  • Avoid broad-spectrum insecticide use near retained and rehabilitated bat habitat.
  • Keep construction lighting temporary and directional.
  • Use warm, low-glare lighting where lighting cannot be avoided.
  • Inspect rehabilitation after storms, fire and maintenance works.

Rehabilitation actions: 4. Long-term monitoring

Monitor retained roost trees, artificial roosts, rehabilitation plots and nearby flight paths for use and condition. Use emergence watches, acoustic detectors and inspections suited to the site.

Monitor during warmer active periods as well as after major habitat works. Interpret winter non-detections cautiously because bats may enter torpor.

Compare results with the baseline and adjust weed control, lighting, planting or roost management when use is low or habitat is deteriorating.

  • Record bat calls, emergence activity, roost condition, box occupancy, vegetation survival and threats.
  • Check for signs of colony use without opening occupied hollows or boxes unnecessarily.
  • Set review points in the rehabilitation plan and retain monitoring data with the project records.
  • Continue monitoring for as long as required by the approval, SMP or site management plan.

Rehabilitation actions: 5. Handover and maintenance

Assign responsibility for retained trees, bat boxes, rehabilitation areas, lighting controls and future inspections before the construction project closes.

Include roost and breeding-place controls in the operational environmental management plan. Future pruning, demolition, drainage and fire management can also affect bats.

Train maintenance crews to recognise roost signs and use the same stop-work pathway as the construction team.

  • Keep habitat maps and artificial roost locations in the asset register.
  • Inspect structures after storms, vandalism and major maintenance.
  • Reinstate damaged exclusion barriers or roost structures promptly.
  • Review the plan when new bat records, colonies or breeding places are detected.

Sources