Fauna Spotters logo

Orange-bellied Frog (Anstisia vitellina)

The Orange-bellied Frog is a very small, threatened Western Australian frog restricted to riparian habitat in the Witchcliffe to Karridale area, north of the Blackwood River and north-east of Augusta. It breeds on land in moist litter and vegetation, has very limited movement, and can be harmed by clearing, soil disturbance, fire, hydrology change, poor water quality and disease spread on development sites.

Conservation status

Commonwealth, EPBC Act 1999: Vulnerable.

Western Australia, Biodiversity Conservation Act 2016: Vulnerable.

Breeding season

Orange-bellied Frogs breed in moist terrestrial nests from late winter to early summer. Males call mainly from September to October, while eggs and developing young remain in the nest. Avoid clearing, drainage changes and dewatering near moist creekline ground from late August to December.

Reproductive mode: Terrestrial egg laying. Eggs are placed in small clusters within moist soil depressions or burrows, under vegetation near creeks.

Clutch size: About 10 to 12 eggs on average. Other sources describe the clutch as a small cluster.

Incubation or gestation: An exact incubation period is not recorded. Eggs and larvae develop within the broken jelly mass, with development into frogs taking about three months.

Size at hatching or birth: Not recorded. Tadpoles can reach nearly 2 cm, but they do not swim or feed externally.

Age at maturity: Recruitment into the breeding population occurs at about 2 to 3 years of age.

Nest or egg sites: Small flask-shaped burrows or depressions in moist peat or soil, covered by litter, moss or dense vegetation near streams and creeks.

Breeding frequency: Not recorded.

Confirm timing locally before works, because calling and breeding activity vary with seasonal conditions, rainfall and temperature.

  • Calling: Males call from late August to early or mid December. Calling peaks in September and October.
  • Egg laying: Eggs are laid on land in small clusters from late winter to summer, with the documented breeding period extending from late August to early or mid December. Eggs are placed in moist soil depressions or burrows near creeks.
  • Eggs in nest: Eggs and larvae develop inside the jelly mass in terrestrial nests during the breeding season. The larvae do not swim freely or feed before metamorphosis.
  • Froglets: Development into frogs takes about three months, so froglets may begin leaving nests from around November after early-season laying and may continue into the following summer. Exact emergence months are not recorded.
  • Active period: Species-specific activity months outside the calling season are not recorded. As a general guide for a small frog in the cooler, wetter south-west climate, plan for most surface activity from May to December, with local conditions controlling movement.
  • Highest clearing risk: Clearing, ground disturbance, drainage changes and dewatering pose the greatest risk from late August to December, when calling males, eggs, developing larvae and newly metamorphosed frogs use moist ground nests and dense cover. Risk is highest from September to November.

Identification

The Orange-bellied Frog is a tiny, cryptic frog that is usually detected by its call rather than by sight. Searches should focus on moist ground beneath dense vegetation and litter near suitable creekline habitat.

The species is no bigger than a thumbnail and has a distinctive bright yellowish-orange underside covering the front half to two thirds of the belly. The dorsal surface is not described in the supplied documents as having a feature that is more diagnostic than the ventral colour.

Approximate length: Generally less than 2.5 cm.

Weight: Not reported in the supplied documents.

Identification: Call and similar species

Males produce a series of short clicks, similar to the sound of pulling the tongue from the roof of the mouth. The call is similar to that of the White-bellied Frog, but the Orange-bellied Frog has about 9 to 15 pulses, commonly described as about 11 clicks per burst, compared with about 11 to 18 pulses in the White-bellied Frog.

The yellowish-orange belly is the main visual distinction from the White-bellied Frog, which has a white or faint yellow ventral surface. Call pulse rate changes with temperature, with warmer frogs calling faster.

  • Use the belly colour and call together when identification is important.
  • Do not rely on call counts alone where temperature, distance or overlapping calls may affect the recording.

Identification: Field signs

Direct observations are difficult because adults call from small depressions or flask-shaped burrows in moist soil, usually beneath litter, moss or dense vegetation. Eggs and developing larvae remain within a jelly mass in the nest, so there is no free-swimming tadpole or open-water egg mass to use as a normal search sign.

The species has no reported tracks, scats, sloughs or eyeshine that can be used reliably for field detection. Handle any captured frog carefully and minimise contact with skin, soil, water and vegetation between sites.

  • Record calling males, call location, weather, vegetation cover and the condition of the surrounding moist ground.
  • Treat small moist depressions beneath litter or dense vegetation as potential breeding sites and avoid trampling them.

Distribution: National range

The Orange-bellied Frog is endemic to Western Australia and has one of the most restricted distributions of any mainland Australian vertebrate. It is known from a small group of creek systems in the lower south-west.

The species is recorded only in Western Australia. Its known range is in jarrah forest in the Witchcliffe to Karridale area, north of the Blackwood River and north-east of Augusta.

The regional setting includes the Blackwood Plateau and the Leeuwin-Naturaliste area. The species occurs in riparian habitat within broad valleys that drain south towards the Blackwood River.

States: Western Australia only.

Extent of occurrence: About 6.3 km².

Area of occupancy: Just over 0.2 km², approximately 20 ha.

Distribution: Known subpopulations

The species is known from the lower reaches of six creeklines. The largest known population occurs along Spearwood Creek, upstream of the Denny Road crossing to the Blackwood River.

Five additional populations occur in smaller nearby creek systems between Denny Road and the Blackwood River. All known Orange-bellied Frog sites were reported from State forest in the earlier recovery plan, with later recovery planning identifying conservation protection within Blackwood River National Park.

  • Treat each creekline and occupied moist ground unit as a separate management area because movement and gene flow between populations are very limited.
  • Do not assume that nearby suitable habitat will be recolonised after a local extinction.

Distribution: Population information

A precise total population size is not provided in the supplied documents. Monitoring has used counts of calling males, and the available monitoring dataset for this species is limited to shorter-term monitoring at selected populations.

Genetic and mark-recapture studies indicate very little movement between populations. This means that local losses may be permanent and that each occupied creekline has high conservation value.

Known creekline populations: Six.

Monitoring information: Three time series for Orange-bellied Frog were included in the pilot Threatened Frog Index, with an average time-series length of 5.7 years.

Adult male movement: 95 per cent moved less than 5 m between seasons within a year and less than 20 m between years.

Habitat: Habitat type

The species depends on very localised moist riparian habitat rather than on the full area of surrounding forest. Suitable habitat is concentrated in valley floors and creekline vegetation where moist ground, litter and dense cover persist.

The Orange-bellied Frog occurs in jarrah forest riparian habitat in broad, U-shaped valleys, sometimes close to streams. The occupied creek valleys can be up to 100 m wide and have headwaters at elevations of at least 120 m.

The regional climate is wet, with mean annual rainfall of about 1,100 to 1,200 mm. More than 75 per cent of rainfall occurs from May to September.

Valley form: Broad, U-shaped valleys, up to about 100 m wide.

Headwater elevation: At least 120 m at the sources of occupied sites.

Regional rainfall: About 1,100 to 1,200 mm annually, with more than 75 per cent from May to September.

Habitat: Vegetation and structure

Recorded habitat includes dense riparian shrubland and moist ground cover. Plant species associated with occupied sites include Homalospermum firmum, Pseudoloxocarya grossa, Loxocarya sp. nov., Boronia molloyae, Acacia uliginosa, Agonis linearifolia and Astartea fascicularis.

The species is usually hidden in litter, moss or dense vegetation. Retaining the structure and moisture of the riparian layer is therefore important during clearing, access and construction works.

  • Map moist riparian depressions, dense ground cover and creekline vegetation separately from the wider forest vegetation.
  • Keep machinery, stockpiles, spoil, sediment and access tracks out of occupied and potentially occupied moist ground.

Foraging habitat: Diet

Species-specific feeding studies were not detailed in the supplied documents. The available information supports treating this frog as a small terrestrial insectivore that feeds within moist ground cover.

Adult frogs are predators of moving small animals. Small frogs generally eat insects, and may also take mites, spiders, snails, earthworms and other small invertebrates.

The supplied documents do not identify particular prey species, food plants or a measured foraging range for the Orange-bellied Frog.

Adult diet: Small moving animals, especially insects and other small invertebrates.

Measured foraging range: Not reported.

  • Retain moist litter, moss, low vegetation and invertebrate habitat around occupied creeklines.
  • Avoid pesticide drift, chemical overspray and sediment or pollutant inputs that could reduce terrestrial invertebrate prey or affect the frog through its permeable skin.

Breeding habitat

Breeding is fully terrestrial. Males call from moist ground in small burrows beneath litter or dense vegetation, and the eggs develop in place without a free-swimming tadpole stage.

Males form calling groups through spring and call from small, flask-shaped burrows or depressions in moist soil. Mating and egg laying occur inside the burrow, and the eggs are left unattended.

Eggs hatch and the larvae develop and metamorphose within the jelly surrounding the egg mass. The larvae do not swim freely or feed before metamorphosis. Juveniles then leave the nest, and recruitment into the breeding population occurs at about 2 to 3 years of age.

Breeding season: Late August to early or mid December; spring calling is generally September to November.

Peak calling: September and October.

Clutch size: Average about 10 to 12 eggs.

Incubation and development: Eggs and larvae develop within the jelly mass in the terrestrial nest; an exact incubation period is not reported.

Age at maturity: Recruitment into the breeding cohort occurs at about 2 to 3 years of age.

Lifespan: Up to six years, although many adults breed for only one season because adult survival is low.

  • Protect moist soil depressions, litter, moss and dense vegetation during the breeding season.
  • Do not clear, burn, compact, drain or flood occupied breeding ground without a species-specific assessment and approved controls.

Breeding habitat: Breeding-site features

Suitable breeding sites are small moist depressions or burrows in soil under litter, moss or dense vegetation, often on moist ground close to streams. The species does not require a permanent open-water breeding pool.

Breeding habitat can be damaged by removal of the ground layer, soil compaction, altered drainage, sediment deposition, fire and loss of vegetation cover.

  • Search moist ground and dense cover near occupied creeklines during the peak calling period, particularly from September to October.
  • Maintain the local drainage pattern and prevent runoff, sediment and contaminants from entering breeding depressions.

Sheltering habitat: Ground refuges

The species shelters and breeds at ground level. Its small size, cryptic behaviour and very limited movement make undisturbed ground cover important.

Adults are usually concealed among dense vegetation, leaf litter, moss and moist soil. Calling males use small flask-shaped burrows or depressions, and the same ground layer provides shelter around breeding sites.

No measurements are provided for burrow dimensions, refuge depth or the area used by an individual frog.

Burrow or nest size: Not reported.

Shelter type: Small depressions or flask-shaped soil burrows beneath litter, moss or dense vegetation.

  • Retain continuous litter, moss, low vegetation and moist soil around creekline habitat.
  • Use marked exclusion zones to prevent trampling, vehicle access, excavation and storage of materials on potential refuge sites.

Sheltering habitat: Site hygiene

Amphibian chytrid fungus is present in south-west Western Australia and has been detected in Orange-bellied Frog populations. People can spread the pathogen on contaminated footwear, equipment, soil, plant material and water.

  • Use amphibian hygiene procedures between sites, including cleaning and disinfecting boots and equipment where required.
  • Do not move frogs, tadpoles, water, soil or contaminated equipment between creeklines.

Threats: Clearing and physical disturbance

The Orange-bellied Frog has a very small range, low fecundity and little movement between populations. Disturbance at one creekline can therefore have a disproportionate effect on the species.

Clearing or disturbance of riparian vegetation, moist ground and litter can remove shelter and breeding sites. Soil disturbance, compaction, siltation, plantation establishment, harvesting, road construction and track construction can damage the microhabitat or increase population isolation.

Development actions near known sites should be assessed for direct effects on vegetation structure, soil, drainage, access and the ability of frogs to move between occupied areas.

  • Avoid clearing occupied creekline habitat and moist ground depressions.
  • Keep access tracks, laydown areas, machinery and spoil outside riparian and potential breeding habitat.
  • Prevent new barriers that increase isolation between occupied creeklines.

Threats: Fire

Fire can destroy the litter, vegetation and moist soil structure used for calling and breeding. The supplied recovery information recommends excluding fire from specific swamp or riparian habitat where possible because fire can expose soil, increase weed invasion and reduce habitat quality.

Fire planning should account for the breeding season and the risk of intense summer fire. The species response to different fire regimes remains incompletely understood.

  • Do not burn occupied or potential breeding habitat without a site-specific fire assessment.
  • Maintain firebreaks and access controls that protect riparian frog habitat without disturbing the habitat itself.
  • Manage ignition and wildfire risk around known sites during the dry season.

Threats: Hydrology and water quality

Changes that increase or decrease the hydrological balance can affect moist breeding depressions and riparian vegetation. Potential impacts include dams, drainage, groundwater extraction, altered runoff and changes in the catchment vegetation.

Fertiliser runoff, pesticide runoff, chemical overspray and sediment can affect water and soil quality. Although breeding is terrestrial, the frogs depend on moist ground and have permeable skin.

  • Maintain natural drainage and avoid diverting, concentrating or removing water from occupied habitat.
  • Control sediment, fertiliser, pesticide and other chemical runoff from works areas.
  • Assess groundwater extraction and nearby water allocation changes for effects on soil moisture and riparian vegetation.

Threats: Disease and introduced animals

Chytrid fungus is a recognised threat to Australian amphibians and has been detected in Orange-bellied Frog populations in south-west Western Australia. It can spread by direct contact between frogs and through infected water, soil, footwear and equipment.

Feral pigs can disturb soil and riparian habitat. Weeds can alter vegetation structure, increase fuel loads and reduce the quality of ground cover.

  • Apply frog hygiene protocols before entering and when leaving each occupied creekline.
  • Control feral pig access and soil disturbance around known habitat where authorised.
  • Prevent the introduction and spread of weeds through clean machinery and control of soil and plant material movement.

Survey methodology: 1. Calling surveys

The Orange-bellied Frog, Anstisia vitellina, is a small, cryptic frog that breeds terrestrially in moist ground under litter and dense vegetation. Surveys should target calling males during the breeding season and avoid disturbing egg masses, burrows and wet riparian habitat.

Survey during the breeding season, from late August to early or mid-December, with peak calling activity from September to November.

Listen for the male call, a series of about 9 to 15 short clicks. Calling activity is affected by temperature, with warmer frogs calling faster.

Search moist ground near streams, especially beneath litter, moss and dense vegetation, where males use small flask-shaped burrows.

Breeding season: Late August to early or mid-December

Peak calling period: September to November

Call: About 9 to 15 short clicks per series

Breeding habitat: Moist soil under litter, moss or dense vegetation, often near streams

  • Conduct repeated listening surveys during suitable conditions rather than relying on a single visit.
  • Record the number and location of calling males, the survey date, start and finish times, weather, recent rainfall, observer names and the survey area.
  • Use low-impact searches and do not excavate burrows or remove dense ground cover unless authorised under the project fauna management plan.

Survey methodology: 2. Habitat and targeted searches

Inspect broad, moist riparian valleys, swampy ground and creek margins within the species' known range near the Blackwood River, north-east of Augusta, Western Australia.

Treat all moist depressions, dense ground cover and small burrows as potential breeding habitat, even when frogs are not detected.

The species' recorded extent of occurrence is about 6 square kilometres, while suitable breeding habitat occupies about 0.2 square kilometres.

Extent of occurrence: About 6 square kilometres

Suitable breeding habitat: About 0.2 square kilometres

Known distribution: State forest north of the Blackwood River, north-east of Augusta, Western Australia

  • Map creeklines, moist depressions, dense litter, moss, low vegetation and proposed disturbance areas before works begin.
  • Search adjoining retained vegetation where works could alter drainage, soil moisture, vegetation cover or movement between occupied sites.
  • Use night searches where safe and appropriate, because males call during the breeding season and are usually well hidden among vegetation.

Survey methodology: 3. Repeated population monitoring

For projects near known habitat, use fixed transects or fixed search areas so results can be compared between visits.

The historical recovery programme monitored nine Orange-bellied Frog sites three times during the peak breeding season, from mid-September to late October.

Counts of calling males are used as an estimate of local population size, but low counts do not demonstrate absence.

Historical survey effort: Three monitoring visits at each of nine sites during mid-September to late October

Population measure: Number of calling males

Movement between seasons: Most adult male movement was less than 5 metres within a year and less than 20 metres between years

  • Repeat surveys across the breeding season and record each calling male location without double-counting individuals between adjacent search areas.
  • Use the same route, search area, observer method and timing on repeat visits where possible.
  • Obtain advice from the relevant Western Australian fauna authority before using capture, mark-recapture, environmental DNA or other specialist methods.

Survey methodology: Minimum effort and reporting

  • Do not describe the species as absent unless the survey effort, timing, weather, search area and detection limitations support that conclusion.
  • Use the breeding-season calling surveys and habitat assessment above as the minimum project basis, then increase effort where habitat is small, fragmented, difficult to access or close to known records.
  • Have a suitably experienced amphibian ecologist set the final survey design where the project could affect moist riparian habitat.
  • Submit confirmed records, including negative results where required, to the relevant Western Australian wildlife database and the Australian national species records system.
  • Report coordinates, date, survey method, effort, number of calling males, photographs or recordings where available, habitat condition and any disease-control measures used.

Before habitat disturbance: Avoid and minimise

Plan the project around the frog's very small range, low mobility and specific breeding sites. Avoid direct disturbance to moist riparian habitat and prevent changes to soil moisture, drainage, vegetation cover and site connectivity.

Avoid clearing or disturbing known or potential breeding habitat, including moist depressions, creek margins, dense litter and vegetation under which males call and eggs develop.

Retain riparian vegetation, ground cover, moss, litter and the soil structure around calling sites.

Do not alter drainage, groundwater conditions or surface flows through or beside habitat. The species is vulnerable to changes in the hydrological balance and water or soil quality.

Adult movement: Most monitored adult males moved less than 5 metres within a year and less than 20 metres between years

Known populations: Six creek systems were recorded in the original recovery plan

Key risk: Local extinction may be permanent because natural dispersal and recolonisation are limited

  • Keep works outside occupied creeklines and moist breeding areas wherever practicable.
  • Use existing roads and disturbed areas for access, compounds and services rather than entering retained frog habitat.
  • Prevent sediment, fertiliser, chemical spray and other pollutants from reaching frog habitat.
  • Retain vegetated links between occupied creek systems and nearby suitable habitat because the species has very limited movement and low natural recolonisation capacity.

Before habitat disturbance: Approvals and work planning

The species is listed as Vulnerable under the EPBC Act and as Vulnerable in Western Australia. Confirm current listing information and approval requirements before finalising the design.

The recovery plan identifies clearing, vegetation disturbance, soil disturbance, altered hydrology, reduced water or soil quality and increased isolation as actions that may significantly affect the species.

Commonwealth status: Vulnerable under the EPBC Act

Western Australian status: Vulnerable

Potentially significant actions: Habitat clearing, soil disturbance, hydrological change, pollution and increased isolation

  • Refer the action under the EPBC Act where the project could significantly affect the species or its habitat.
  • Obtain any required Western Australian fauna, clearing, vegetation, water, fire and threatened-species approvals before work starts.
  • Prepare a fauna management plan that defines survey methods, exclusion zones, hygiene controls, spotter catcher authority, stop-work triggers, animal handling, incident response and reporting.
  • Schedule clearing and ground disturbance outside the breeding period where practicable, while recognising that moist habitat and egg masses can remain sensitive outside the calling season.
  • Stage works so that retained habitat remains connected and the smallest practicable area is opened at one time.

Before habitat disturbance: Pre-clearance preparation

Complete a pre-clearance habitat inspection and targeted breeding-season survey before machinery enters the work area.

Mark approved limits of disturbance, moist depressions, creeklines, dense ground cover, known records and all retained habitat on plans and on the ground.

  • Install exclusion fencing around retained habitat and no-go areas where fencing can be maintained without damaging frog habitat.
  • Brief all machinery operators, supervisors and fauna spotter catchers on the frog's appearance, call, habitat and stop-work procedures.
  • Clean and disinfect boots, vehicles, tools and machinery before entering and between sensitive sites, using a method approved for amphibian chytrid control.
  • Keep soil, mud, water, plant material and sediment from being moved between frog sites.
  • Confirm access, lighting and emergency arrangements for night surveys and animal collection.

During habitat disturbance: Daily controls and supervision

Use a trained fauna spotter catcher and a supervisor with authority to stop work. Work slowly around moist ground and retained vegetation, and treat every small burrow, litter patch and creek margin as potential frog habitat.

Inspect exclusion fencing, sediment controls, drainage controls and no-go markers at the start of each shift.

Keep machinery within the approved disturbance footprint and maintain the agreed buffer around retained habitat.

Use a fauna spotter catcher to inspect the immediate work area before clearing, trenching, grading, vehicle movement or material placement.

Stop work if controls fail, water quality deteriorates, soil or mud is moved between sites, or the approved disturbance footprint cannot be maintained.

  • Keep a daily record of weather, work area, machinery, spotter catcher, inspections, fauna observations, captures, releases, injuries, incidents and corrective actions.
  • Use amphibian hygiene procedures between sites, including cleaning and disinfection of footwear, equipment and machinery that contacts soil, mud or water.
  • Do not release untreated wash water, sediment or disinfectant into frog habitat.
  • Limit night lighting, noise and vehicle movement near occupied habitat during the breeding season.

During habitat disturbance: Animal finds and handling

If an Orange-bellied Frog is found, stop nearby work and keep machinery, people and vehicles away from the animal and its immediate habitat.

Only an appropriately authorised and experienced person should capture or handle the frog.

Keep handling to the minimum needed for identification, protection and relocation, and follow the approved hygiene and animal-welfare procedure.

  • Photograph the frog in place where this can be done without disturbance, and record its exact location and habitat.
  • Relocate the frog only when authorised by the fauna management plan and only to nearby retained habitat that has suitable moist ground cover and is outside the work area.
  • Do not move frogs, eggs, soil, litter, water or vegetation between populations without specific approval and a documented translocation plan.
  • Place an injured frog in a clean, suitable container and transfer it promptly to an approved wildlife carer or veterinarian, recording the chain of custody.
  • If eggs or a suspected occupied burrow are found, stop work and obtain direction from the project ecologist or relevant wildlife authority before proceeding.

During habitat disturbance: Habitat features and stop-work triggers

This species does not use tree hollows as a breeding feature. Its eggs and larvae develop in jelly within small soil depressions or burrows beneath litter and dense vegetation.

Treat moist soil, litter, moss, dense ground cover, creek margins and small depressions as habitat features that must not be disturbed without ecological approval.

Breeding mode: Direct development within the egg mass, with no free-swimming or feeding tadpole stage

Typical egg-laying site: Small flask-shaped burrows or depressions in moist soil under litter, moss or vegetation

  • Stop work for any confirmed frog, egg mass, occupied burrow or unapproved disturbance to a moist breeding area.
  • Stop work if clearing exposes or dries a suspected breeding depression, changes water flow, causes sediment entry or damages retained riparian vegetation.
  • Do not remove logs, rocks, litter or dense vegetation from retained habitat unless the fauna management plan specifically allows it.
  • Escalate any chytrid suspicion, unusual amphibian mortality or disease-control failure to the project ecologist and relevant authority.

After habitat disturbance: Post-clearance checks

Close out the work only after the disturbed area and retained habitat have been checked. Confirm that drainage, soil moisture, vegetation cover and hygiene controls remain suitable for the species.

Have the fauna spotter catcher and ecologist inspect the completed work area, access routes, stockpiles, trenches, drainage lines and retained habitat for frogs, egg masses, injured animals and trapped fauna.

Backfill or cover trenches and pits as soon as practicable, or provide safe escape routes until they are closed.

Remove temporary materials, spoil and sediment that could enter retained creeklines or moist breeding areas.

Repair damaged exclusion fencing and keep no-go areas protected for the duration of the project.

  • Complete a final search after machinery leaves and before the area is handed back to the contractor or land manager.
  • Check that no soil, mud, plant material, water or equipment has been transferred from the work area to another frog site.
  • Record all animals found, including animals released, injured or dead, and submit required records to the relevant wildlife database and regulator.

After habitat disturbance: Monitoring and compliance reporting

Monitor retained and rehabilitated habitat during the next suitable breeding seasons where the project affected known or potential habitat.

Use repeat calling surveys and fixed monitoring areas so changes in the number of calling males can be compared over time.

The recovery programme used annual monitoring and evaluated trends using calling-male data.

Monitoring indicator: Number of calling males

Historical monitoring approach: Fixed transects or sites surveyed during the breeding season

  • Report any decline, loss of calling activity, new disturbance, weed invasion, fire damage, feral pig damage or hydrological change to the project environmental officer and land manager.
  • Maintain records of monitoring dates, observers, weather, effort, calling males, habitat condition, photographs and management actions.
  • Continue monitoring for the period specified in the approval, fauna management plan or offset plan, and implement corrective action when success measures are not met.

After habitat disturbance: Offsets and residual impacts

First avoid and minimise impacts within the project footprint. If a significant residual impact remains, obtain advice on any offset or approved conservation measure required under the EPBC Act or Western Australian approvals.

Do not treat translocation as a routine substitute for retaining occupied habitat. The species has strong population-level genetic differences and very limited movement between sites.

  • Document the area and condition of habitat lost, retained, restored and protected.
  • Ensure any offset or conservation action protects suitable moist riparian habitat and addresses the species' identified threats.
  • Obtain specific approval for any translocation, captive breeding or release proposal, including source population, disease controls, genetic considerations, receiving habitat and monitoring.

Rehabilitation actions: Restore breeding habitat

Rehabilitation should recreate moist, shaded, undisturbed breeding ground rather than only planting trees. The aim is to retain or restore the soil moisture, litter, dense vegetation and hydrological conditions used by calling males and developing eggs.

Reinstate natural drainage and shallow moist depressions without creating permanent open water, because the species lays eggs on land and develops directly within the egg mass.

Restore dense native ground cover, litter, moss and low vegetation beneath and beside riparian shrubs and trees.

Use locally appropriate native plant species from the surrounding jarrah forest and riparian community, subject to advice from the Western Australian land manager and recovery team.

Habitat setting: Riparian habitat in jarrah forest, including broad moist valleys and creek margins

Breeding substrate: Moist soil under litter, moss or dense vegetation

Egg development: Within jelly in the burrow, without a free-swimming tadpole stage

  • Do not import soil, litter, water, logs or vegetation from another frog population unless approved and treated under the disease-control plan.
  • Replace disturbed topsoil and leaf litter from the same site where it is clean and its movement is authorised.
  • Retain or reinstate fallen logs, coarse woody debris and other shaded ground cover without burying or compacting potential calling sites.
  • Prevent cattle, vehicles and repeated pedestrian access from trampling restored moist ground.

Rehabilitation actions: Weeds, predators, fire and disease

Control weeds before they replace native ground cover or alter fuel loads and soil moisture in restored habitat.

Inspect for feral pig damage and control pigs through approved programmes where they disturb soil or frog habitat.

Manage fire to protect moist breeding habitat. The recovery plan recommends excluding fire from specific swamp or riparian habitat where practicable and using firebreaks to reduce the risk of fire entering it.

Apply amphibian hygiene controls during all rehabilitation, monitoring and maintenance visits.

  • Do not burn restored riparian or swamp habitat unless the approved fire plan demonstrates that burning is necessary and safe for the species.
  • Keep herbicides, fertilisers and wash-down water out of frog habitat.
  • Remove or isolate weed infestations without stripping the litter and ground structure used by frogs.
  • Inspect restored sites after fire, flooding, drought, pig disturbance and major construction events.

Rehabilitation actions: Success measures and adaptive management

Assess whether restored habitat remains moist, shaded, connected and free from compaction, weeds, pollution and uncontrolled fire.

Use breeding-season calling surveys to test whether frogs are using restored or retained habitat.

A practical success measure is stable or increasing calling-male counts at retained or restored sites, with no loss of naturally occurring populations from controllable project impacts.

Recovery goal: Maintain or increase the current extent and viability of the species

Species recovery indicator: Calling-male numbers and persistence of naturally occurring populations

Key rehabilitation risks: Drying, compaction, weed invasion, fire, feral pigs, pollution and altered drainage

  • Set baseline monitoring before disturbance where practicable and compare results for at least the monitoring period required by the approval.
  • Record the number of calling males, occupied or potentially occupied burrows, vegetation cover, litter condition, weed cover, soil disturbance, water quality incidents and predator damage.
  • Repair failed drainage, fencing, revegetation or erosion controls promptly.
  • Review the rehabilitation method with the ecologist and land manager when monitoring shows declining calling activity or loss of suitable moist ground.

Sources