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Dusky Leaf-nosed Bat (Hipposideros ater)

The Dusky Leaf-nosed Bat is a small, high-frequency echolocating microbat found in the Northern Territory, Queensland and Western Australia. On works sites, caves, mines, rocky shelters and other dark roosts need checking because a single maternity roost can support many local bats. It is listed as least concern in Australia, but it is a colonial breeder and breeding places receive additional protection in Queensland.

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.

Breeding season

The Dusky Leaf-nosed Bat is a colonial cave-roosting microbat, but species-specific breeding months are poorly documented in Australia. As a practical guide, use the general microbat pattern of breeding and raising young from spring to late summer, with local timing varying between regions and years.

Breeding mode: Live-bearing mammal. It breeds in colonies or shared maternity roosts. Most Australian microbats produce one pup in the warmer months, usually spring to late summer.

Litter size: Usually one pup per year for Australian microbats. A Dusky Leaf-nosed Bat litter size has not been specifically recorded here.

Gestation, fledging and weaning: Not recorded for the Dusky Leaf-nosed Bat.

Breeding places and roosts: The species is an obligate cave-roosting bat. Recorded roost settings include dark, warm caves, old mines and spaces beneath rock piles. It may share roosts with other microbat species. Other microbat breeding places can include fissures, loose bark, culverts, bridges and buildings, but use by this species should be confirmed on site.

Colony size and site fidelity: Typical colony sizes and site fidelity are not recorded. Treat any shared roost as potentially significant because a colony or maternity roost can hold a substantial part of the local population.

How to recognise an active breeding place: Confirmation should be based on pregnant or lactating females, pups or dependent young. Emergence watches, Anabat or similar acoustic detectors, harp traps or mist nets, and inspection with an endoscope or pole camera can help confirm use. Avoid entering or handling bats unless the work is appropriately authorised and supervised.

Practical protection: Before clearing, survey hollow-bearing trees, caves, mines, fissures and built structures. Use two-stage or soft felling for hollow-bearing trees where required, and install exclusion devices outside the maternity season. Bat boxes are a supplementary measure and do not replace protection of an existing breeding place.

Breeding timing may shift between years and regions, so treat September to February as a planning guide and confirm local roost use before clearing or construction.

  • Breeding and births: Use September to February as the practical breeding window for this poorly documented species, based on the general pattern for Australian microbats.
  • Dependent pups in maternity roosts: Dependent young may be present during the warmer-month breeding period, so avoid disturbance of suspected maternity roosts during this window.
  • Roost occupancy and foraging activity: Cave and mine roosts may be used throughout the year, and the species has been recorded as a cave-roosting bat that feeds on flying insects.
  • Active maternity roost checks: During the breeding window, use emergence watches and targeted acoustic or capture surveys to check whether a roost contains females and young before works begin.
  • Highest clearing risk: Clearing, tree felling, demolition or disturbance is most likely to harm dependent young or disrupt a maternity roost from September to February.

Identification: Appearance and size

The Dusky Leaf-nosed Bat is a very small leaf-nosed bat. Reliable field identification usually requires a combination of roost inspection, expert assessment and high-frequency acoustic data.

The species weighs about 4.2 g. A dependable external description and measurements for use in routine site work are not well established, so avoid relying on photographs alone.

Handle any captured bat only under an approved fauna survey or relocation procedure. Confirm identification with a qualified bat ecologist where the result affects clearing or construction decisions.

  • Look for a small microbat using dark, warm roost spaces.
  • Record the roost feature, number of bats, behaviour and any associated species.

Identification: Calls and similar species

The echolocation call is a high-duty-cycle, constant-frequency signal. Its characteristic frequency is about 157 kHz, with a reported range of 152 to 162 kHz in the Top End reference data.

This frequency is higher than the reference calls reported for several other northern leaf-nosed bats. Acoustic identification should still be checked by an experienced analyst, especially where the detector or microphone has limited high-frequency sensitivity.

Reference call: About 157 kHz

Call group: High-duty-cycle, constant-frequency

  • Use an Anabat or similar detector capable of recording well above 150 kHz.
  • Review call shape and frequency with site, habitat and roost evidence.
  • Do not treat a single weak or clipped call as a confirmed record.

Identification: Field signs

Look for small dark droppings below roost entrances, on cave floors, ledges, bridge structures or mine workings. Droppings may be mixed with those of other microbats and are not diagnostic on their own.

Whitewash, staining, urine marks, a musky odour and accumulated insect remains can indicate a regularly used roost. These signs are more useful when concentrated below a sheltered entrance or ceiling area.

There are no nests. Young are carried and later fly from the roost, so maternity evidence is based on bats and their use of the site rather than nest material.

  • Fresh droppings or concentrated guano
  • Urine staining or whitewash on ledges and walls
  • Repeated bat calls or movement at dusk
  • Bats clustering on warm, dark surfaces

Distribution: Australian range

In Australia, the Dusky Leaf-nosed Bat is mapped in the Northern Territory, Queensland and Western Australia. Records and survey experience are strongest in the monsoon tropics of the Northern Territory and in northern Queensland.

In the Northern Territory, the species has been recorded in the Top End, north of 18 degrees south. It has also been recorded in North Queensland.

The species is mapped in Western Australia, although site-level distribution and regional limits should be checked against current fauna databases before works begin.

  • Northern Territory, especially the Top End
  • Queensland, including North Queensland
  • Western Australia

Distribution: Taxonomic forms

Two Australian forms are recognised in the material used for field planning: the eastern Dusky Leaf-nosed Bat, Hipposideros ater aruensis, and the western Dusky Leaf-nosed Bat, Hipposideros ater gilberti.

Use the current taxonomic treatment and local database records when assigning a record to a form or region.

Eastern form: Hipposideros ater aruensis

Western form: Hipposideros ater gilberti

Distribution: Planning a survey

A map record does not show that a bat is using a particular tree, cave or structure. Search for roost features and survey likely flight paths, especially near rocky country, escarpments, caves and old mine workings.

Use local records, landform mapping and advice from the project ecologist to set the survey area. Acoustic results are more useful when collected over several suitable nights rather than from one isolated detector deployment.

  • Check nearby caves, mines, rocky overhangs and artificial structures.
  • Review records from the Atlas of Living Australia and relevant state databases.
  • Consider habitat links between roosts, water and insect-rich vegetation.

Habitat: Landforms and landscape setting

The Dusky Leaf-nosed Bat is strongly associated with cave-roosting landscapes. On a development site, focus first on rocky landforms, escarpments, caves, mine workings and other dark cavities, then assess nearby vegetation and water as supporting habitat.

Top End records are associated with rugged country, rocky slopes, escarpments and areas near rivers. The species was detected most often at escarpment sites in one Top End habitat comparison.

Some records also come from woodland settings. A site without a visible cave may still support bats if nearby cliffs, rock piles, culverts, bridges or old workings provide shelter.

  • Escarpments and steep rocky slopes
  • Rock outcrops, boulder piles and overhangs
  • Caves, sinkholes and old mine entrances
  • Rivers and other landscape features linking roosts with feeding areas

Habitat: Vegetation and fire context

The species has been recorded in the monsoon tropics, including woodland and areas with high canopy cover. It forages in cluttered habitat rather than open airspace alone.

Maintain vegetation around known or potential roosts where practical. Clearing can remove insect habitat, alter shade and temperature, and reduce safe movement routes between roosts and feeding areas.

  • Monsoon woodland and adjoining riparian vegetation
  • Vegetated edges and gaps near rocky country
  • Areas with canopy cover and a reliable supply of flying insects

Habitat: Site assessment

Before clearing, walk the site in daylight and map all cavities and structures that could provide a dark, warm, stable roost. Inspect features that may be overlooked during a standard vegetation survey.

Record access points, internal conditions, evidence of bats, nearby water, vegetation cover and the proposed disturbance footprint.

  • Map caves, fissures, loose rock, old mines, culverts, bridges and buildings.
  • Photograph entrances and signs without entering unsafe workings.
  • Refer unstable mines, confined spaces and deep caves to suitably trained personnel.

Foraging habitat: Foraging style

The Dusky Leaf-nosed Bat feeds on small flying insects and often hunts in cluttered airspace. Protecting the roost alone may not retain the habitat needed for nightly feeding.

The species is classified with bats that forage in background-cluttered and highly cluttered space. This includes edges, gaps and narrow flight paths through vegetation or rocky habitat.

It often hunts in groups, then returns to a roost to rest and digest its food.

  • Vegetated edges and canopy gaps
  • Narrow spaces beside rock faces, gullies and dense vegetation
  • Sheltered flight paths near water and roost entrances

Foraging habitat: Diet

The recorded diet includes several insect orders. Lepidoptera made up about 58% of the average dietary volume in one Top End study, followed by beetles, cockroaches, termites, flies and other insects.

The diet indicates broad insect use, but the available dietary sample was small. Avoid treating one prey profile as a complete description of local feeding requirements.

  • Moths and other Lepidoptera
  • Beetles
  • Cockroaches and termites
  • Flies, lacewings, ants and other small arthropods

Foraging habitat: Works site measures

Retain connected vegetation between roost features and likely feeding areas where the project allows. Limit unnecessary night lighting near cave entrances, mine portals, bridges and known flight paths.

Schedule noisy or bright works away from active roost entrances where practicable. Use the project ecologist to set controls when acoustic or emergence data indicate regular use.

Breeding habitat: Maternity roost features

Species-specific breeding information for the Dusky Leaf-nosed Bat is limited. As a microbat, it should be managed as a colonial breeder because females may gather in shared maternity roosts during the warmer months.

A maternity roost is a dark, sheltered place where females raise young. For this species, caves and old mines are especially relevant, along with other stable cavities such as rock fissures, culverts, bridges or buildings where suitable conditions exist.

The same broad roost landscape may contain day roosts, night roosts and maternity areas. Do not assume that a quiet entrance is unused.

  • Warm, dark cave chambers and ledges
  • Old mine adits and shafts
  • Deep rock fissures and cavities
  • Sheltered artificial structures with restricted light and stable temperature

Breeding habitat: Breeding timing

Most microbats give birth to one pup a year in the warmer months, usually from spring to late summer. Local timing can vary with rainfall, temperature and region.

Treat the warmer months as a period requiring extra care unless a bat ecologist has confirmed that the relevant roost is not being used for breeding.

  • Avoid disturbance at suspected maternity roosts during the breeding period.
  • Do not seal, exclude or clear a roost until breeding status has been assessed.
  • Recheck timing advice for the local region before setting construction dates.

Breeding habitat: Confirming a maternity roost

Confirmation is strongest when pregnant or lactating females, dependent pups or recently volant young are recorded. A cluster of bats alone shows use, but does not confirm breeding.

Use a combination of internal inspection where safe, emergence watches, acoustic monitoring and targeted trapping under the direction of an experienced bat ecologist.

  • Pregnant or lactating females
  • Pups attached to females or clustered in the roost
  • Young bats emerging or flying at dusk
  • Repeated use of the same roost across the breeding period

Sheltering habitat: Natural roosts

Known sheltering habitat includes dark, warm caves, old mines and spaces under piles of rocks. Project surveys should also consider natural and artificial cavities that provide darkness, protection from weather and stable temperatures.

The Dusky Leaf-nosed Bat is described as an obligate cave-roosting species. Search rocky landscapes thoroughly, including small entrances and fissures that may not appear on broad-scale mapping.

Roosts may be shared with other microbat species. Mixed-species use is common enough that all bats and signs should be recorded rather than assigning a site to one species from appearance alone.

  • Caves and cave-like cavities
  • Old mine workings
  • Rock piles, boulder gaps and fissures
  • Sheltered ledges and deep crevices

Sheltering habitat: Artificial and modified roosts

Culverts, bridges, buildings and other structures can provide suitable dark cavities, particularly where they are warm, sheltered and rarely disturbed. These features need inspection before demolition, sealing or major repairs.

Tree hollows are important for many Australian microbats, but this species is chiefly associated with caves. Treat any suitable hollow or cavity as a potential roost until survey evidence rules it out.

  • Culverts and bridge joints
  • Roof spaces, wall cavities and unused buildings
  • Tree hollows, fissures and loose bark where present
  • Mine portals and adits

Sheltering habitat: Survey and handling methods

Use Anabat or similar acoustic detectors to identify high-frequency activity. Emergence watches can show whether bats leave a cavity and can help locate entrances that are not obvious during the day.

Harp traps or mist nets may assist with species confirmation when used by trained personnel and under the relevant approvals. Inspect suspected roost trees with an endoscope or pole camera where safe.

  • Acoustic monitoring at entrances and along likely flight paths
  • Dusk emergence watches
  • Harp trap or mist net surveys for confirmation
  • Endoscope or pole camera inspection of accessible cavities

Colonies and breeding places: What a colony looks like

A colony or maternity roost is a shared breeding place where bats gather in close association. Colony size for the Dusky Leaf-nosed Bat is not well established, so manage any repeatedly used roost as significant until its role is understood.

A colony may occupy a cave chamber, mine adit, rock cavity, culvert, bridge space or building cavity. Bats may cluster on a ceiling or wall, use several chambers, or move between nearby roost features.

Numbers can range from a few bats to many bats, depending on the site and season. Do not use a low daytime count to dismiss a roost, because many bats may be away feeding or concealed in cracks.

Typical colony size: Species-specific colony sizes are not well established. Treat any shared breeding roost as significant

  • Repeated bat activity at one entrance
  • Several bats emerging over an extended period at dusk
  • Guano, urine staining or whitewash concentrated below a cavity
  • Pups, lactating females or young bats

Colonies and breeding places: Site fidelity and active use

Bats commonly return to suitable roosts, but the strength of site fidelity for this species has not been established. A roost can also be used differently across the year.

An active breeding place may show fresh droppings, odour, staining, repeated emergence, social calls, clustered adults or young. Confirm use with more than one sign where possible.

  • Fresh guano below ledges or entrances
  • Regular emergence on suitable evenings
  • Pregnant or lactating females
  • Pups or newly flying young
  • Recent acoustic activity at the cavity

Colonies and breeding places: Managing a breeding place

Colonies need special care because one roost can hold a large share of the local population. Disturbance, exclusion or sealing at the wrong time can separate mothers from young or cause bats to abandon a roost.

For tree or structure removal, use a staged or soft-felling approach where a suitable cavity is involved. Exclusion devices should be installed only outside the maternity season and after confirming that young are not dependent.

Queensland requirement: Tampering with the breeding place of a least concern colonial breeder requires the high risk species management program pathway

  • Survey before clearing, demolition, blasting or mine closure.
  • Use two-stage or soft felling for hollow-bearing trees where relevant.
  • Keep exclusion devices one-way and install them outside the maternity season.
  • Use bat boxes only as a supplementary measure, not as an automatic replacement for a natural roost.

Threats: Roost destruction and disturbance

The Dusky Leaf-nosed Bat is listed as least concern, but local roosts can still be sensitive to works. The main risks are loss or disturbance of roosts, loss of feeding habitat and changes to the surrounding landscape.

Mining, cave modification, demolition, blasting, drilling and sealing of old workings can remove or disrupt roosts. Human entry, lights, noise and repeated visits can also disturb bats in cave habitats.

Inspect caves, mine workings, rock piles, bridges, culverts and buildings before works. Do not enter unsafe or confined spaces without the required training and controls.

  • Cave blasting or excavation
  • Mine closure or portal sealing
  • Demolition or repair of roosting structures
  • Uncontrolled access to active roosts

Threats: Loss of feeding habitat

Clearing can reduce insect prey and remove sheltered flight paths between roosts and feeding areas. Loss of woodland, riparian vegetation and vegetation around rocky country can increase the distance bats need to travel.

Retain vegetation links and avoid unnecessary clearing around known roosts. Control dust, lighting and night-time disturbance near roost entrances where practicable.

  • Clearing woodland and riparian vegetation
  • Removal of canopy cover and edge habitat
  • Loss of vegetation around escarpments and rocky shelters
  • Artificial lighting near roost entrances and flight paths

Threats: Agriculture and land degradation

Agricultural expansion and land degradation can reduce insect habitat and alter the vegetation surrounding roosts. Erosion, sediment movement and repeated disturbance may also affect caves, mine entrances and rocky shelter sites.

Manage runoff and access around sensitive roost features. Keep machinery, spoil and construction materials away from entrances and drainage lines.

Threats: Compliance and work controls

The Dusky Leaf-nosed Bat is not listed as endangered, vulnerable or near threatened in Australia. It remains a protected native animal, and its colonial breeding behaviour means a least concern listing does not remove the need for roost assessment.

In Queensland, DETSI treats animals that co-exist in close association for breeding as colonial breeders. Tampering with a breeding place requires the high risk species management program pathway rather than the low risk pathway used for other least concern animals.

  • Engage a suitably qualified fauna spotter catcher and bat ecologist before works near a suspected roost.
  • Document the survey method, roost status, timing controls and exclusion decision.
  • Stop work and reassess if pups, lactating females or a large emergence is found.

Survey methodology: 1. Desktop assessment

The Dusky Leaf-nosed Bat is a small, high-frequency microbat that is poorly known across much of its range. Use more than one survey method, particularly where caves, mines, rocky shelters, hollow-bearing trees or built structures may be affected.

Map caves, old mines, rock piles, escarpments, rocky gullies, hollow-bearing trees, bridges, culverts and buildings within and near the work area.

Review recent fauna records and local knowledge. Give particular attention to areas near escarpments and other rocky terrain, and to sites with warm, dark shelter.

Treat all potential roosts as suitable until a competent ecologist has assessed them. The species is strongly associated with cave roosts, but microbats may also use fissures, loose bark, tree hollows and built structures.

  • Check landholder, mine, cave and infrastructure records before entering a potential roost.
  • Identify access points, roost entrances, flight paths, feeding areas and places where works could alter airflow, light, noise or access.
  • Confirm whether the work area is in Queensland, the Northern Territory or Western Australia, then check the relevant approval and permit requirements.

Survey methodology: 2. Acoustic and capture surveys

Use an Anabat or similar full-spectrum detector at cave entrances, rocky shelters, likely flyways, culverts, bridges and along vegetation edges. The Dusky Leaf-nosed Bat has a high-duty-cycle constant-frequency call centred at about 157 kHz, with a recorded range of 152 to 162 kHz.

Record full-spectrum files where possible. High-frequency calls can be missed or weakened by unsuitable detector settings, distance, vegetation and weather.

Use harp traps or mist nets only where the survey is led by a suitably experienced and authorised person. Place equipment clear of roost entrances and flight paths where practicable, and minimise handling time.

  • Survey during suitable night conditions, avoiding heavy rain and strong wind.
  • Use repeated detector deployments where a single night cannot resolve use of the site.
  • Record detector model, settings, calibration, location, date, start and finish time, weather, habitat, detector height and any call identification confidence.
  • Do not rely on call frequency alone where species have overlapping calls or the recording quality is poor.

Survey methodology: 3. Roost and breeding-place checks

Carry out emergence watches at potential roosts from before sunset until activity has clearly finished. Watch cave, mine, rock, tree and structure entrances, and record the direction and approximate intensity of emergence.

Inspect hollow-bearing trees, culverts, bridges and buildings from the ground. Where safe and authorised, use an endoscope or pole camera to inspect hollows, fissures and cavities. Do not enter unstable mines or caves without the required specialist assessment and permits.

A maternity roost or other breeding place is confirmed by evidence such as pregnant or lactating females, dependent pups, repeated use by females with young, or pups observed at the roost. A roost where young are raised is a breeding place.

  • Record roost type, entrance dimensions where safe to measure, height, aspect, internal conditions, evidence of bats and evidence of breeding.
  • Use acoustic monitoring, emergence observations and targeted capture together when the first survey does not establish whether the site is active.
  • Schedule additional checks if bats are detected but breeding status is uncertain.
  • Assume a colony may extend beyond the visible roost entrance.

Survey methodology: 4. Colony interpretation and survey records

The Dusky Leaf-nosed Bat is treated as a colonial breeder for Queensland management purposes. Colony sizes for this species are not well established, so do not assume that a small emergence represents a small or unimportant population.

Colonies may occupy dark, warm caves, old mines and rock shelters. Other microbats may share the same roost. Suitable sites can also include fissures, hollow trees, loose bark, culverts, bridges and buildings.

Record evidence of site fidelity, including repeated detections at the same entrance, repeated emergence, fresh droppings, staining, roost odour and regular return to a previously used shelter.

  • Map all entrances and nearby alternative shelters.
  • Record the number of bats observed only as an estimate, with the method and observation period stated.
  • Keep raw acoustic files, photographs, capture records, weather data, maps and field notes with the project records.
  • Report uncertain identifications for expert review rather than forcing a species call.

Before habitat disturbance: 1. Avoidance, approvals and permits

Plan works around the risk of disturbing a roost or breeding place. Avoidance is preferred, especially for a maternity roost or a colony that may support a large share of the local population.

Redesign the work footprint to retain caves, mines, rock shelters, hollow-bearing trees and established roost structures wherever practicable.

Obtain project-specific environmental approvals before disturbance. Consider whether an EPBC Act referral is required, and confirm the requirements of the relevant state or territory authority.

In Queensland, obtain the required high risk species management program for tampering with the breeding place of a least concern colonial breeder. A low risk program for other least concern animals is not the appropriate pathway where a colonial breeding place is affected.

Check additional permit requirements for fauna survey, capture, handling, relocation, cave or mine entry, tree removal and work on public land in Queensland, the Northern Territory and Western Australia.

  • Document the approval pathway, conditions, contact officers and stop-work triggers in the construction environmental management plan.
  • Obtain written approval before disturbing a confirmed or suspected breeding place.
  • Do not rely on the species being listed as least concern to justify disturbance of a breeding place.

Before habitat disturbance: 2. Pre-clearance survey and seasonal planning

Complete a targeted pre-clearance survey close enough to the planned works to reflect current site use. Recheck sites where conditions have changed or where earlier surveys found bats.

Most microbats give birth to one pup a year in the warmer months, usually from spring to late summer. Avoid disturbing a maternity roost during this period unless the relevant authority has approved the action and suitable controls are in place.

There is no reliable species-specific migration schedule for this bat. Plan around confirmed local roost use rather than assuming that bats will leave seasonally.

  • Survey all potential roosts before finalising the clearing method.
  • Use emergence watches and acoustic monitoring where a roost may be occupied but daytime inspection is inconclusive.
  • Allow enough time for identification, approvals and contingency measures before vegetation or structure removal begins.
  • Record whether females, pups or other evidence of breeding are present.

Before habitat disturbance: 3. Buffers, exclusion and alternative roosts

Set a site-specific no-go buffer around each active roost, maternity roost, colony and flight path. The ecologist and relevant authority should determine the buffer using roost sensitivity, work type, noise, vibration, lighting, access and the risk of collapse or blockage.

Do not seal, fumigate, smoke, illuminate or otherwise exclude bats from an active maternity roost. Exclusion devices may be considered outside the maternity season, but only after confirming that dependent young are absent and obtaining the required approval.

Provide a clear alternative plan before any roost is disturbed. Bat boxes or other roost structures are supplementary measures and do not replace retention of a functioning natural roost.

  • Fence and sign the buffer before plant arrives.
  • Prevent storage, vehicle access, generators and night lighting within the buffer.
  • Use one-way exclusion devices only under an approved method and with follow-up checks.
  • Do not use bat boxes as a reason to remove a suitable cave, mine, hollow tree or established roost.

Before habitat disturbance: 4. Induction and stop-work planning

Induct every worker, subcontractor and fauna spotter catcher before work starts. Show photographs or maps of no-go areas, roost entrances, likely bats and the reporting chain.

Give the fauna spotter catcher authority to stop work immediately when a bat, colony, roost, breeding place or unexpected habitat feature is found.

Nominate an ecologist or environmental manager who can assess the find and contact the regulator or permit holder without delay.

  • Explain that workers must not touch, chase, feed or release bats.
  • Keep people, dogs, vehicles and machinery away from roost entrances.
  • Place stop-work details and emergency contacts in plant cabins and site offices.
  • Confirm the location of the nearest wildlife carer or veterinarian before clearing begins.

During habitat disturbance: 1. Sequential clearing

Use a slow, supervised clearing sequence. Stop work whenever the approved method no longer matches the conditions on the ground.

Retain all identified roosts and potential breeding places until the final stage of the work, or until the approved exclusion and relocation method has been completed.

Clear surrounding vegetation progressively so animals have an opportunity to move away from the work area. Avoid sudden removal of cover around a roost entrance.

Use two-stage or soft felling for hollow-bearing trees where removal is approved. Cut limbs and sections slowly, lower them where practicable, and leave sections undisturbed for inspection before relocation or disposal.

  • Use a fauna spotter catcher during all clearing that may affect roosting or sheltering habitat.
  • Check each felled hollow-bearing section, stump, cavity, loose bark slab and debris pile before moving it.
  • Pause work during hot, wet or otherwise unsafe conditions if handling could increase injury risk.
  • Keep an exclusion zone around any tree or structure being inspected.

During habitat disturbance: 2. Active colonies and breeding places

If an active breeding place or colony is found, stop work and protect the roost entrance and surrounding habitat. Do not block the entrance or separate adults from pups.

Keep noise, vibration, dust and lighting away from the roost. Prevent workers and machinery from entering the shelter unless entry is approved and necessary for assessment.

Contact the project ecologist and the relevant approval or permit authority. Resume only under a revised, approved method.

  • Record the location, roost type, evidence of use, estimated number of bats and whether pups or lactating females are present.
  • Extend the buffer if bats change their flight path, circle the work area, repeatedly return to the roost or show signs of distress.
  • Do not relocate a colony or pups unless the approved plan specifically allows it and the work is led by an authorised specialist.
  • Treat a shared roost as a sensitive site for all bats present.

During habitat disturbance: 3. Handling and injured animals

Only authorised and trained people may capture, handle, transport or release bats. Avoid bare-hand contact. Bats can bite, and handling must follow the project wildlife safety procedure.

If a bat is found on the ground, in a tree section or inside a building, keep people away and obtain instructions from the fauna spotter catcher or wildlife carer. Do not release it without an assessment.

For an injured, entangled, heat-affected or grounded bat, place it in a secure, ventilated container only if this can be done safely by an authorised person. Keep it dark, quiet and at a stable temperature while arranging veterinary or wildlife-carer care.

  • Do not give food or water unless directed by a wildlife carer or veterinarian.
  • Record the exact find location and condition before moving the animal.
  • Follow workplace exposure procedures immediately after any bite or scratch and seek medical advice.
  • Do not handle a bat that cannot be safely contained. Isolate the area and call the approved responder.

During habitat disturbance: 4. Records and communication

Maintain a clearing log for every work area. Record detections, captures, injuries, roosts, breeding evidence, stop-work events, approvals, releases and disposal or retention of hollow-bearing material.

Photograph roost entrances, habitat features and any animal injury where this can be done without causing further disturbance.

Give the site supervisor a daily update while sensitive habitat or an active roost is being managed.

  • Record date, time, location, weather, activity, people involved and action taken.
  • Save acoustic files and identify the detector and settings used.
  • Notify the regulator or approval holder within the timeframe required by the permit or management program.
  • Keep a map showing cleared areas, retained habitat, buffers and any replacement roost structures.

After habitat disturbance: 1. Post-clearance checks

Do not close out the fauna task when machinery leaves. Check the site, confirm that controls worked and document any change in roost use or animal condition.

Inspect cleared areas, retained trees, felled hollow sections, structures and access tracks for trapped, injured or displaced bats. Check cavities and debris before removal.

Recheck retained roosts after noisy or high-vibration work, especially where blasting, piling, demolition, rock breaking or major earthworks occurred nearby.

Confirm that roost entrances remain open, stable and free of waste, sediment, dust, temporary fencing and construction materials.

  • Complete checks during daylight for sheltering animals and at dusk where roost activity needs confirmation.
  • Use an endoscope or pole camera only where safe and authorised.
  • Record all dead, injured, relocated or newly detected animals.
  • Escalate any continuing disturbance or evidence of abandonment to the project ecologist.

After habitat disturbance: 2. Relocated animals and replacement roosts

Track every animal that is moved, including the capture location, release or holding location, condition, handler and outcome.

Where an approved relocation has occurred, check the release site for shelter, temperature, predators, access, food-producing vegetation and disturbance. Do not assume that release proves successful settlement.

Inspect replacement bat boxes or artificial roost structures for stability, weather exposure, access and signs of use. These structures are supplementary and may not replace the function of a natural cave, mine or hollow.

  • Maintain the approved exclusion or protection measures until the ecologist confirms that the site is safe to reopen.
  • Do not move a bat again merely because it is using a different temporary shelter.
  • Use acoustic monitoring, emergence observations or inspection to assess use of replacement structures.
  • Report failed, damaged or unused structures and adjust the design or location under ecological advice.

After habitat disturbance: 3. Monitoring and reporting

Complete monitoring required by the approval, species management program or permit. Where a colony or maternity roost was affected, monitoring should cover both the roost and nearby alternative shelters.

Compare post-work observations with the pre-work baseline. Look for continued emergence, changes in activity, new roost entrances, altered flight paths and signs of breeding.

Provide a close-out report that explains what was cleared, what was retained, which controls were used and whether any incidents occurred.

  • Include maps, photographs, survey dates, methods, weather, acoustic results, capture records and breeding evidence.
  • Report non-compliance, injury, death, unexpected roost discovery and unauthorised disturbance through the required pathway.
  • Keep monitoring records with the project environmental file.
  • Use qualified reviewers for uncertain call identifications or unusual roost findings.

After habitat disturbance: 4. Incident review

Review every stop-work event, injury, mortality, roost disturbance and failed exclusion. Include the fauna spotter catcher, supervisor, ecologist and relevant contractor.

Change the clearing method, induction, buffer or timing where the review identifies a foreseeable risk that was not controlled.

  • Record the cause, immediate response, corrective action and person responsible.
  • Share lessons with the next clearing crew before work resumes.
  • Update the fauna management plan and emergency contacts when site conditions or personnel change.

Rehabilitation actions: 1. Restore roost and foraging habitat

Rehabilitation should restore shelter, feeding habitat and safe movement around retained roosts. Natural roosts and mature vegetation should be retained wherever possible, with artificial structures used only where they suit the site and the approved design.

Retain caves, mines, rocky shelters, hollow-bearing trees, fissures and loose bark that remain safe and suitable. Protect roost entrances from stock, vehicles, rubbish, altered drainage and uncontrolled access.

Replant cleared edges with locally appropriate native vegetation that supports flying insects and reconnects shelter with nearby feeding areas. Protect regenerating plants from fire, grazing and compaction according to the site plan.

Leave suitable fallen hollow sections or retained tree features where they can remain stable and do not create a safety hazard.

  • Stabilise erosion around caves, mine entrances, rocky shelters and drainage lines.
  • Keep roost entrances free of weeds, sediment, spoil and construction waste.
  • Maintain natural vegetation corridors between roosts and nearby feeding habitat.
  • Avoid creating new access tracks or bright work areas beside retained roosts.

Rehabilitation actions: 2. Bat boxes and artificial roost structures

Use bat boxes, artificial nest sites or other roost structures only after an ecologist confirms that they suit the local species and site. The Dusky Leaf-nosed Bat is associated particularly with dark, warm cave-like shelters, so a generic tree bat box may not provide an equivalent roost.

Install structures before the original shelter is lost where practicable. Place them away from intense lighting, vibration and regular human access, and provide safe flight access.

Treat artificial structures as supplementary habitat. Their placement, design, materials and maintenance should be set out in the approved rehabilitation plan.

  • Use several suitable structures where the project assessment supports them, rather than relying on one replacement site.
  • Record structure location, orientation, height, installation date and design.
  • Inspect mounts, entrances, weathering, predators, pests and signs of use without unnecessary disturbance.
  • Do not seal or remove an artificial roost that is occupied without ecological assessment and approval.

Rehabilitation actions: 3. Weeds, water and lighting

Control weeds around retained roosts and revegetation areas without blocking entrances or releasing chemicals into caves, mines, rock shelters or drainage lines.

Maintain natural drainage and clean water sources where they occur. Prevent sediment, hydrocarbons and construction waste from entering roosts or nearby waterways.

Use the lowest practical level of artificial light. Direct lights away from roost entrances, vegetation corridors and likely flight paths, and use timers or motion controls where compatible with safety.

  • Use local native plants suited to the soil and rainfall of the site.
  • Inspect rehabilitation after heavy rain and repair erosion promptly.
  • Keep permanent lights shielded and avoid lighting cave, mine or bridge entrances.
  • Record weed treatment, water protection measures and lighting changes in the rehabilitation log.

Rehabilitation actions: 4. Long-term monitoring

Monitor retained roosts, replacement structures and revegetation for the period required by the approval. Monitoring should assess habitat condition as well as bat use.

Use emergence watches, acoustic detectors and targeted inspections to determine whether bats continue to use the site. Repeat surveys under comparable conditions where results will be compared over time.

Review monitoring results with the project ecologist and adapt maintenance, lighting, weed control or protection measures if use declines.

  • Record roost condition, bat activity, breeding evidence, weeds, erosion, lighting and human access.
  • Retain raw acoustic recordings and photographs for comparison between monitoring events.
  • Inspect replacement structures after severe weather and repair them promptly.
  • Continue protection of successful roosts after construction completion.

Sources