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Eastern delicate mouse (Pseudomys mimulus)

The eastern delicate mouse is a very small native rodent of eastern and northern Australia. It occurs from eastern Queensland and northern New South Wales to the Mount Isa area and Groote Eylandt, and may be encountered in grassland, woodland and other non-rainforest habitats. Its small size, cryptic appearance and recent recognition as a separate species mean that clearing assessments should not rely on records identified only as delicate mouse.

Conservation status

New South Wales, Biodiversity Conservation Act 2016: Endangered.

Commonwealth, EPBC Act 1999: Vulnerable. Listed under the EPBC Act as the Pilliga Mouse (Pseudomys pilligaensis), which is now treated as part of this species.

Breeding season

A species-specific annual breeding calendar has not been published. The calendar below therefore marks the full year as a potential management period rather than assigning unsupported breeding peaks.

Species-specific breeding months, movement dates, litter size, age at maturity and lifespan are not well documented. The general hydromyine review describes pregnancy of about 32 days in many species, but this value should not be treated as confirmed for Pseudomys mimulus.

  • Highest clearing risk: Treat all months as potential clearing risk because breeding and dependent-young periods are unresolved. Disturbance can remove habitat, refuges and food at any time.

Identification

The eastern delicate mouse is a tiny, lightly built native rodent. It is difficult to identify reliably in the field because it closely resembles other delicate mouse lineages and other small Pseudomys species.

Adults may weigh as little as 6 g, with the delicate mouse group typically weighing about 6 to 7 g. A full external description for Pseudomys mimulus, including body length, tail length, pelage colour, ear dimensions and hind-foot measurements, has not been published.

The species is best treated as a small delicate mouse in the field, rather than identified from appearance alone. The eastern, western and northern delicate mice look very similar despite being genetically distinct.

Typical adult mass: About 6 to 7 g

Reliable field identification: Not generally possible from appearance alone where other delicate mouse lineages or small Pseudomys occur

Identification: Distinguishing it from similar mice

Pseudomys mimulus differs from Pseudomys delicatulus and Pseudomys pilbarensis mainly through genetics, chromosome arrangement, reproductive morphology and subtle external differences. The eastern lineage includes Queensland and Groote Eylandt animals, while P. delicatulus is the northern lineage and P. pilbarensis is the western lineage.

A specimen or tissue sample that may affect a clearance decision should be referred to an appropriately qualified mammalogist. Genetic confirmation may be needed, particularly near areas where delicate mouse lineages meet or where records are based on the former broad concept of Pseudomys delicatulus.

  • Do not assign a delicate mouse record to Pseudomys mimulus solely from a photograph or general mouse-like appearance.
  • Record the exact capture location, habitat, photographs, measurements and voucher or tissue details where collection is authorised.
  • Check current taxonomy when reviewing older records labelled Pseudomys delicatulus or delicate mouse.

Identification: Field signs

No diagnostic tracks, scats, calls, nests, eyeshine or other field signs have been identified for Pseudomys mimulus. Small rodent signs should therefore be treated as non-diagnostic unless linked to a captured or genetically identified animal.

Species-specific measurements for tracks, scats, nests and refuge entrances have not been published.

  • Use live trapping, handling by trained personnel and appropriate taxonomic assessment where species-level confirmation is required.
  • Do not infer presence or absence from the lack of visible tracks, scats or surface runways.

Distribution: State and regional range

Pseudomys mimulus has a broad but discontinuous eastern Australian distribution. Its recognition as a separate species substantially reduced the former assumed range of the delicate mouse group.

The species occurs through eastern Queensland and northern New South Wales, extends inland around Mount Isa and Boulia in Queensland, and occurs on Groote Eylandt in the Gulf of Carpentaria. The type locality is Groote Eylandt.

The published range spans about 20 degrees of latitude and includes tropical and semi-arid settings. Formal IBRA bioregion names have not been assigned to the known localities.

  • Queensland: eastern Queensland, northern Queensland, the Mount Isa area, the Boulia area and Groote Eylandt.
  • New South Wales: northern New South Wales, including the Pilliga Scrub area mentioned in the range analysis.
  • The species' occurrence in Victoria, South Australia, Western Australia, the Northern Territory mainland, Tasmania and the Australian Capital Territory is not documented.

Distribution: Strongholds and population information

No confirmed population stronghold, total population estimate, density estimate or population trend has been established for Pseudomys mimulus. Mainland populations show high genetic connectivity across the sampled eastern range, while Groote Eylandt is an important named population and type locality.

The species was previously concealed within a much broader delicate mouse taxon. Its actual conservation status and population trajectory require reassessment following the taxonomic split.

Known population size: Not reported.

Population density: Not reported.

Population trend: Not established.

Genetic pattern: Little geographic structure across the sampled eastern Australian distribution, consistent with high connectivity

Habitat: Habitat types

The eastern delicate mouse occupies a wide climatic and vegetation range. The species shows broad environmental tolerance, but no detailed vegetation association or site-scale habitat model has been published.

Records and samples extend from eastern Australian tropical environments to semi-arid woodland around the Pilliga Scrub and inland Queensland. The delicate mouse group inhabits all major Australian biomes except tropical rainforest, although Pseudomys mimulus has a broad range that reaches areas near tropical rainforest.

The species is associated with terrestrial habitats rather than aquatic or estuarine environments. No single preferred vegetation community has been identified.

  • Retain native ground cover and connected habitat around proposed clearing areas where delicate mice may occur.
  • Assess habitat at the site scale rather than assuming that a developed or disturbed margin is unsuitable.
  • Treat records from grassland, woodland, heath-like ground cover and semi-arid vegetation as potentially relevant until the species identity is resolved.

Habitat: Structure and climate

The species occurs across a large climatic gradient, from northern monsoonal regions to semi-arid eastern Australia. Climate strongly influences delicate mouse distributions.

No species-specific elevation limit, minimum patch size, canopy cover requirement, ground-cover height, soil depth or distance to water is provided.

Elevation limit: Not reported

Climate range: Northern monsoonal to semi-arid eastern Australian environments

Rainforest use: The delicate mouse group is reported from all major Australian biomes except tropical rainforest

Foraging habitat: Diet and feeding sites

The eastern delicate mouse's diet and foraging behaviour are not well documented. Retain the ground layer and native seed-producing vegetation used by small Pseudomys rodents.

A species-specific diet for Pseudomys mimulus is not stated. Other Pseudomys species described in the review eat seeds, grasses, forbs, leaves or other plant material, and the delicate mouse group is part of the same hydromyine radiation.

The mouse is expected to forage close to ground level, but its foraging height, daily foraging distance, home range and food density have not been specified.

Confirmed food plants or prey: Not specified for Pseudomys mimulus

Foraging range: Not reported

Likely food category from related Pseudomys: Seeds, grasses, forbs and other plant material

  • Retain native grasses, forbs, seed-bearing plants, leaf litter and low ground cover within and beside the work area.
  • Avoid treating bare ground, recently slashed areas or weed-dominated margins as equivalent to intact foraging habitat.
  • Where clearing is unavoidable, inspect and manage the ground layer before machinery enters the site.

Breeding habitat: Breeding biology

Breeding information for Pseudomys mimulus is limited. Taxonomic research confirms reproductive differences within the delicate mouse group, but no species-specific breeding season or litter record has been published.

The eastern delicate mouse has sperm and chromosome differences from the other delicate mouse lineages, which contribute to reproductive isolation. These findings confirm that reproductive biology is relevant to identification, but they do not establish the species' breeding timing or productivity in the field.

As a small hydromyine rodent, it may have a relatively short generation time, but species-specific age at maturity, litter size and lifespan have not been published.

Breeding season: Not reported for Pseudomys mimulus

Litter size: Not reported for Pseudomys mimulus

Gestation: Not reported for Pseudomys mimulus; about 32 days is described for many hydromyine rodents generally

Age at maturity: Not reported

Lifespan: Not reported

Breeding habitat: Breeding habitat

No species-specific nest site, litter chamber or breeding shelter has been described. Retaining dense ground cover, leaf litter and undisturbed soil is appropriate because these features provide potential protection for small ground-dwelling rodents and their young.

Because breeding timing is unresolved, avoid assuming that winter or the dry season is free of dependent young.

  • Search for small rodent shelter sites before clearing in suitable native ground cover.
  • Stage clearing so that escape habitat remains connected to retained vegetation.
  • Use an approved fauna spotter catcher where animals, nests or occupied refuges are encountered.

Sheltering habitat: Known refuge information

The eastern delicate mouse's burrows, nests and refuge dimensions have not been documented. Site management should nevertheless protect low, connected cover and avoid unnecessary disturbance of soil and litter.

No confirmed shelter type, burrow depth, entrance size, nest dimensions, hollow use or refuge density is provided for Pseudomys mimulus.

Other small hydromyine rodents use burrows, cracks, dense vegetation, pebble mounds or shallow shelters, but those structures cannot be assigned to the eastern delicate mouse without species-specific evidence.

Burrow dimensions: Not reported

Nest dimensions: Not reported

Known use of tree hollows: Not reported

  • Inspect dense grass, leaf litter, fallen timber, rock piles, soil cracks and other low refuges before ground disturbance.
  • Retain connected ground cover around retained habitat and avoid isolating small patches with access tracks or stockpiles.
  • Do not destroy or fill a suspected occupied refuge until it has been assessed under the project fauna management procedure.

Threats: Clearing and fragmentation

The eastern delicate mouse has a much smaller recognised range than the former broad delicate mouse taxon. Clearing, predation and climate change are identified concerns for delicate mice, while the effects of fragmentation, fire, roads, disease and hydrology change have not been quantified for this species.

Habitat clearing is identified as an immediate threat to delicate mice. Clearing can remove feeding cover and refuges, isolate local populations and increase exposure to predators and vehicles.

The species' broad genetic connectivity suggests that retaining links between habitat patches is relevant, especially where works occur in eastern Queensland, northern New South Wales, inland Queensland or around Groote Eylandt.

  • Avoid clearing native ground cover where practicable.
  • Survey and manage the full disturbance footprint, including temporary access tracks, laydown areas, spoil areas and easements.
  • Maintain vegetated connections between retained patches where practicable.
  • Remove slash and stockpiles only after fauna inspection and under the approved clearing procedure.

Threats: Predators, fire and roads

Feral cats are identified as a threat to delicate mice. Road mortality, fire impacts and the response of Pseudomys mimulus to different fire regimes have not been quantified.

Loss of ground cover after clearing or fire may increase exposure to predators. Project controls should therefore retain unburnt shelter where safe and avoid creating long, narrow strips of isolated cover.

  • Control food waste and other attractants that may increase predator activity around work sites.
  • Plan vehicle movements to reduce night driving through retained habitat where practicable.
  • Do not burn cleared material or conduct planned fire in retained potential habitat without considering fauna shelter and seasonal risk.
  • Inspect areas affected by fire before clearing or earthworks because animals may be concentrated in remaining cover.

Threats: Climate, disease and hydrology

Climate models cited for the delicate mouse group suggest that up to 95 percent of current delicate mouse habitat could become unsuitable by 2100 under a moderate future warming scenario. This is a group-level projection and should not be treated as a precise forecast for every Pseudomys mimulus site.

Introduced disease is identified as a potential threat to delicate mice. No particular disease, hydrology impact or species-specific response to altered drainage has been established.

  • Avoid altering drainage, inundation patterns or soil moisture in retained habitat unless the project assessment has addressed these effects.
  • Prevent the spread of soil, plant material and potentially contaminated equipment between sites using the project's hygiene procedures.
  • Treat climate refuges, connected habitat and sites with persistent native ground cover as important areas for retention where practicable.

Survey methodology: 1. Confirm habitat and survey scope

The eastern delicate mouse is a very small native rodent, with adults weighing as little as 6 grams. It occurs in eastern Queensland and northern New South Wales, including sandy grasslands, and is also known around Mount Isa, Boulia and Groote Eylandt. No species-specific survey guideline or prescribed survey effort has been published, so the project ecologist should confirm the applicable state protocol before fieldwork.

Complete a desktop review and walkover before selecting survey sites.

Prioritise sandy grasslands and other sandy, open habitats within or near the proposed disturbance area.

Consider the species' broad recorded distribution, which extends through eastern Queensland and northern New South Wales and includes Groote Eylandt, Mount Isa and Boulia.

Map retained and disturbed habitat separately, and record ground cover, bare sand, dense grass, burrows, logs, rocks and nearby connecting vegetation.

Adult body mass: As little as 6 grams

Recorded distribution: Eastern Queensland, northern New South Wales, Mount Isa, Boulia and Groote Eylandt

Habitat: Grasslands on sandy soils

Survey methodology: 2. Nocturnal searches and spotlighting

Undertake searches after dark because small native rodents can be difficult to detect during daylight.

Search the full disturbance footprint and a representative area of retained habitat, including sandy grassland, dense ground cover and likely shelter sites.

Use consistent transects or fixed search areas so that effort can be compared between sites and nights.

Record start and finish times, personnel, weather, moon conditions, ground conditions, distance searched and all observations or signs.

Species-specific spotlighting effort: Not well documented.

Survey timing: Species-specific seasonal timing is not well documented.

  • Use a red-filtered or otherwise low-impact light where this is consistent with the project fauna management plan.
  • Avoid relying on a single negative spotlighting result, particularly where ground cover is dense or weather is unsuitable.
  • Treat an unidentified small mouse as a potential eastern delicate mouse until it has been identified by an appropriately qualified person.

Survey methodology: 3. Live trapping and supplementary detection

Use live trapping where spotlighting and searches are unlikely to provide adequate detection, subject to state animal ethics, wildlife authority and project approval requirements.

Place traps across the range of mapped habitat conditions, with additional coverage at habitat edges and proposed clearing boundaries.

Use equipment and handling procedures suitable for a 6 gram rodent, and provide shelter, food and protection from exposure in accordance with the approved trapping plan.

Record trap locations, trap nights, bait, weather, captures, recaptures, non-target animals and trap failures.

Species-specific trapping effort: Not well documented.

Relevant taxonomic issue: The former delicate mouse grouping has been divided into three genetically distinct species

  • Do not set or operate traps without the required authorisation and an approved animal welfare procedure.
  • Release animals at the capture point unless the approved fauna plan provides for an authorised relocation.
  • Use additional methods such as remote cameras or hair and sign searches only as supplementary methods. Their detection performance for this species has not been established.

Survey methodology: Minimum effort and reporting

  • Obtain the current state survey guideline and any local authority requirements before finalising the number of nights, trap nights, transect length and search hours.
  • Use more than one survey method where habitat is suitable and the consequence of a missed detection is high.
  • Repeat surveys when weather, ground conditions or access have reduced the likelihood of detection.
  • Report the survey dates, effort, conditions, methods, locations, identification basis, photographs and all negative results.
  • Submit confirmed records and suitable supporting information to the relevant state wildlife database.
  • Update the species name used in project records to Pseudomys mimulus, and retain any former Pseudomys delicatulus identification as a synonym or historic identification where relevant.

Vegetation associations: Rainforest or vine thicket

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

The delicate mouse group inhabits all major Australian biomes except tropical rainforest, although Pseudomys mimulus has a broad range that reaches areas near tropical rainforest.

Automatically indexed from existing profile text. Not a verified preference, mapped occurrence or habitat requirement. Check the original source and regional qualifiers before use.

Evidence: Unreviewed profile-derived candidate

Confidence: Not independently verified

Region: Scope as described in the quoted profile text; not independently verified. Profile states: NSW, NT, QLD.

Habitat use: general

Attribution gap: No sentence-level reference is attached to the original profile block. Review the profile bibliography; this candidate is not source-verified.

Vegetation associations: Woodland

Records and samples extend from eastern Australian tropical environments to semi-arid woodland around the Pilliga Scrub and inland Queensland.

Automatically indexed from existing profile text. Not a verified preference, mapped occurrence or habitat requirement. Check the original source and regional qualifiers before use.

Evidence: Unreviewed profile-derived candidate

Confidence: Not independently verified

Region: Scope as described in the quoted profile text; not independently verified. Profile states: NSW, NT, QLD.

Habitat use: general

Attribution gap: No sentence-level reference is attached to the original profile block. Review the profile bibliography; this candidate is not source-verified.

Vegetation associations: Shrubland

Records and samples extend from eastern Australian tropical environments to semi-arid woodland around the Pilliga Scrub and inland Queensland.

Automatically indexed from existing profile text. Not a verified preference, mapped occurrence or habitat requirement. Check the original source and regional qualifiers before use.

Evidence: Unreviewed profile-derived candidate

Confidence: Not independently verified

Region: Scope as described in the quoted profile text; not independently verified. Profile states: NSW, NT, QLD.

Habitat use: general

Attribution gap: No sentence-level reference is attached to the original profile block. Review the profile bibliography; this candidate is not source-verified.

Ecosystem associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific ecosystem association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Soil and substrate associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific soil association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Water and wetland associations

Source-checked associations and automatically indexed candidates are separated below. An association does not establish site presence, preference or dependence.

No species-specific water association has been indexed or source-checked in this evidence library. This is an evidence gap, not evidence of no association.

Fauna records and mapped habitat: Not yet analysed

Record locations can be overlaid with mapping, but record frequency alone does not measure habitat preference. No species is excluded from desktop assessments by this analysis.

No quality-controlled record-to-map analysis has been completed for this species. The existing generalised distribution dots and indicative range polygons have not been treated as precise occurrence coordinates.

A defensible run needs dated, independently attributable records, coordinate uncertainty, duplicate and captive-record checks, layer versions and regional scope. Preference and absence require additional survey-effort and detection evidence.

Habitat limitations and contrary evidence: No supported exclusion recorded

Not recorded is not the same as cannot occur. Low suitability, resident habitat, breeding habitat and occasional movement are different conclusions.

This library has not established a vegetation, ecosystem or soil-type exclusion for this species. This does not mean all habitat is suitable; the evidence needed to justify an exclusion has not been assembled.

Habitat limitations and contrary evidence: Before using a negative association

  • Confirm the taxon, geographic region, life stage and habitat function covered by the evidence.
  • Check survey methods, season, repeated effort and detectability before interpreting non-detection.
  • Investigate credible contradictory records and microhabitats absent from broad mapping.
  • Do not convert a missing map class, low record count or failed data request into species absence.

Before habitat disturbance: Avoid and minimise

Plan the work around the species' small size, ground-dwelling habitat and uncertain detectability. The main planning focus should be sandy grassland, ground cover and habitat connections, rather than assuming that tree hollows are the primary shelter feature.

  • Retain sandy grassland and other suitable ground habitat within and beside the project area wherever practicable.
  • Avoid unnecessary removal of dense grass, ground cover, logs, rocks and other potential shelter features.
  • Maintain connected strips of suitable habitat between retained areas, especially where clearing would otherwise isolate small patches.
  • Keep disturbance footprints as narrow as practicable and prevent vehicle movement outside approved access routes.
  • Do not treat the absence of a record as proof that suitable habitat is unoccupied.

Before habitat disturbance: Approvals and work planning

  • Check the current EPBC Act status and complete an EPBC referral assessment if the species is listed or if the proposed action may affect a listed matter.
  • Confirm the current state listing, survey requirements, scientific licence requirements, animal ethics requirements and relocation rules before work starts.
  • Prepare a fauna management plan that identifies survey results, habitat to retain, exclusion areas, spotter catcher responsibilities, stop-work triggers and release or veterinary arrangements.
  • Stage clearing so that retained habitat remains connected while fauna searches and pre-clearance activities are completed.
  • Use seasonal timing based on the approved survey and fauna plan, because the breeding season for this species is not well documented.

Before habitat disturbance: Prepare the site

  • Complete a pre-clearance survey immediately before clearing, using the methods and effort approved for the project.
  • Mark the disturbance boundary, retained habitat, access routes, no-go areas and any shelter features identified during the survey.
  • Install exclusion fencing only where it will not funnel animals into machinery paths, isolate them from retained habitat or obstruct their natural movement.
  • Brief machinery operators and the fauna spotter catcher on the species' small size, the approved clearing sequence and the requirement to stop when an animal or possible shelter site is found.
  • Check that capture bags, ventilated containers, gloves, torches, first aid supplies and wildlife contact details are available before clearing begins.

During habitat disturbance: Daily controls

Clearing should proceed in a controlled sequence with the fauna spotter catcher able to see the active work area. The species may be missed easily because adults can weigh as little as 6 grams.

  • Inspect exclusion fencing, no-go markers and retained habitat each day before machinery enters the work area.
  • Maintain a clear communication method between the spotter catcher, supervisor and machine operators.
  • Keep machinery speed low enough for the spotter catcher to inspect ground cover and respond to fauna movement.
  • Clear from the approved retained-habitat edge towards the escape direction identified in the fauna management plan, unless the plan specifies another sequence.
  • Stop work during unsafe weather, poor visibility or any condition that prevents effective fauna observation.

During habitat disturbance: Spotter catcher and machinery interface

  • Require the fauna spotter catcher to remain outside the machine exclusion zone unless the operator has made the area safe and the approved procedure allows entry.
  • Use the stop signal immediately when an animal, burrow, nest, log, rock pile or other possible shelter feature is seen.
  • Allow the spotter catcher to inspect disturbed ground, vegetation piles and machinery buckets before material is moved or loaded.
  • Keep cleared vegetation and spoil separate from retained habitat until the spotter catcher has checked them.
  • Record the location and outcome of every fauna interaction, including animals not captured.

During habitat disturbance: Animal handling and stop-work triggers

Body mass relevant to handling: Adults may weigh as little as 6 grams

Relocation distance: No species-specific distance is provided; use the approved fauna management plan and authority direction

  • Stop work within the affected area if an eastern delicate mouse is found, if identification is uncertain, or if a potential shelter site is exposed.
  • Allow only appropriately authorised and trained personnel to capture, handle or relocate the animal.
  • Use the least stressful handling method approved for a very small rodent and minimise handling time, heat exposure and time in a container.
  • Release a healthy animal into nearby retained habitat that is suitable and connected, unless the approved fauna plan or wildlife authority requires another action.
  • Take an injured, sick or heat-stressed animal to an authorised wildlife carer or veterinarian as soon as practicable, and follow the authority's reporting requirements.
  • Stop work if fencing fails, an animal is repeatedly directed towards machinery, or the approved clearing sequence cannot be maintained.

During habitat disturbance: Habitat feature handling and records

  • Inspect ground cover, logs, rocks, grass clumps and any burrows or cracks before they are removed or crushed.
  • Move salvageable ground features into retained habitat only where this is approved and will not trap or expose animals.
  • Do not assume that hollow-bearing trees are relevant shelter for this ground-associated species, but inspect any tree, log or debris feature identified as habitat during the pre-clearance survey.
  • Keep a daily register of weather, cleared area, machinery hours, fauna observations, captures, injuries, relocations, mortalities, stop-work events and corrective actions.
  • Notify the project ecologist and relevant authority of any confirmed record, injury or mortality within the timeframe set by the approval or fauna plan.

After habitat disturbance: Post-clearance checks

Post-clearance checks should confirm that no animals remain in isolated ground cover or debris and that retained habitat has not been damaged. Records should support both compliance reporting and future survey planning.

  • Inspect the cleared footprint, vegetation piles, spoil, drains and retained habitat edge after each clearing stage.
  • Check for live animals, carcasses, tracks, burrows, trapped fauna and damaged exclusion fencing.
  • Keep machinery out of retained habitat until the post-clearance inspection for that stage is complete.
  • Repeat the inspection after heavy rain, flooding, fire or other events that may move animals into the work area.

After habitat disturbance: Monitoring and controls

  • Maintain exclusion fencing, access controls and no-go markers until the risk of re-entry and secondary injury has ended.
  • Monitor retained sandy grassland and habitat connections for ground disturbance, weed invasion, erosion, loss of cover and increased predator access.
  • Use the approved monitoring method and timing, and compare results with the pre-clearance survey rather than relying only on incidental sightings.
  • Investigate any decline in suitable ground cover or any new records of feral cat activity, introduced disease or habitat clearing.

After habitat disturbance: Reporting and offsets

Known broader threats: Feral cats, habitat clearing and introduced diseases are identified as threats to delicate mice

Projected climate pressure: Models suggest that up to 95% of current delicate mouse habitat could become unsuitable by 2100 under a moderate warming scenario

  • Provide the regulator and project approval holder with the final cleared area, retained area, survey effort, fauna interactions, relocations, injuries, mortalities and corrective actions.
  • Submit verified records, coordinates, photographs and identification evidence to the relevant state wildlife database.
  • Review whether the final impact differs from the approved footprint and obtain further approval if required.
  • Apply any approved offset, restoration or conservation measure required by the state approval or EPBC assessment.
  • Do not claim that an offset replaces avoidance and habitat retention for this species.

Rehabilitation actions: Restore habitat structure

Rehabilitation should recreate connected, low-disturbance sandy grassland with suitable ground cover. No particular plant species, nest box design or restoration density has been identified for the eastern delicate mouse, so rehabilitation targets must be set from local reference sites and the approved plan.

  • Reinstate sandy soil profiles and drainage patterns where earthworks have altered them.
  • Re-establish locally appropriate native grassland and ground-cover species from nearby reference sites.
  • Retain or reinstate logs, rocks, grass clumps and other ground features where they occur naturally in the reference habitat.
  • Avoid creating isolated planted strips that do not connect to retained suitable habitat.
  • Prevent compaction, vehicle access and repeated mowing across rehabilitated sandy grassland.

Rehabilitation actions: Manage threats

  • Control weeds so that native ground cover can establish and shelter is not replaced by dense introduced vegetation.
  • Manage feral cat access and other introduced predators in accordance with the project and authority requirements.
  • Prevent introduced disease risks through hygiene controls for vehicles, equipment and personnel moving between sites.
  • Use fire planning that protects developing ground cover and follows the local ecological burning regime and approval conditions.
  • Do not install nest boxes unless monitoring shows a specific need, because tree hollows and nest boxes are not identified as key habitat features for this species.

Rehabilitation actions: Monitoring and success measures

Species range relevant to rehabilitation planning: The eastern delicate mouse has been recorded across eastern Queensland and northern New South Wales, with records extending from tropical rainforest areas to semi-arid woodland

Habitat planning implication: Use local reference sites because the species shows broad environmental tolerance but is associated with sandy grassland habitat.

  • Monitor plant establishment, native ground-cover continuity, sandy soil condition, weed cover, predator activity and evidence of animal use.
  • Compare rehabilitated areas with nearby retained reference habitat using the same photo points, transects or other approved measures over time.
  • Set success criteria for survival of planted vegetation, ground-cover development, connectivity, erosion control and absence of new barriers.
  • Include targeted eastern delicate mouse surveys when the approved monitoring plan requires evidence of recolonisation or continued use.
  • Continue monitoring for the period required by the approval, and repair failed fencing, erosion, weed outbreaks or other barriers promptly.

Sources