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Giant Burrowing Frog (Heleioporus australiacus)

The Giant Burrowing Frog is a large, fossorial frog of native forest, heath, woodland and small forested streams in coastal New South Wales and Victoria. It is listed as Endangered under the EPBC Act and is sensitive to clearing, compaction, hydrological change, sediment, roads, fire, introduced predators and chytrid disease, so both breeding waterbodies and surrounding non-breeding habitat must be managed on development sites.

Conservation status

Commonwealth, EPBC Act 1999: Endangered.

New South Wales, Biodiversity Conservation Act 2016: Vulnerable.

Victoria, Flora and Fauna Guarantee Act 1988: Critically endangered.

Breeding season

Breeding is mainly in autumn, with calling and movement extending from spring to autumn after heavy rain. Tadpoles remain in pools for 3 to 12 months, so clearing, drainage and dewatering controls may be needed well beyond the period when adults are calling.

Reproductive mode: Egg laying. Thick, foamy egg masses are laid in burrows, crevices or under vegetation near small pools.

Clutch size: About 500 to 800 eggs in the conservation advice, and 700 to 1,200 eggs in the consultation document.

Incubation or gestation: A separate incubation period is not recorded. Eggs develop in a foamy terrestrial or marginal egg mass before flooding releases tadpoles into pools.

Size at hatching or birth: Not recorded.

Age at maturity: About 3 years.

Nest or egg sites: Burrows, empty crayfish holes, crevices and areas under vegetation near small pools, soaks, swamps and small streams. Eggs may be laid out of the water and later flooded into larger pools.

Breeding frequency: Not recorded.

Confirm timing locally before works, because rainfall, heavy storms, water availability and temperature can shift calling, movement, breeding and tadpole development across the species’ south-eastern Australian range.

  • Calling: Males call mainly from February to April, with calling reported from late spring to autumn and occasional records outside that period. Calling is usually after rain, and a summer calling record is documented.
  • Egg laying: Breeding is mainly in autumn, although egg laying can follow spring to autumn rainfall. Egg masses are placed in burrows, crevices or under vegetation near small pools and may be outside the water until flooding occurs.
  • Tadpoles: Tadpoles are recorded mainly from February to May, but development takes about 3 to 12 months. Late developing tadpoles can overwinter and complete development when temperatures rise.
  • Metamorphs: No species-specific months for metamorph emergence are recorded. Metamorphs can be expected when the 3 to 12 month tadpole period ends, including after overwintering tadpoles resume development in warmer conditions.
  • Active period: Adults are most active and move to breeding sites after heavy rain, particularly during spring and autumn. The species is usually detected at night after rain, although calling and movement can occur outside the main period, including after summer rain.
  • Winter inactivity: No defined adult winter inactivity period is recorded. Adults shelter in burrows and leaf litter throughout the year and spend more than 95 percent of their time in non-breeding habitat; late developing tadpoles may overwinter.
  • Highest clearing risk: Risk is highest from late winter through autumn, particularly September to November and March to May, when rain can trigger movement, breeding and egg laying while tadpoles occupy pools. Soil disturbance can harm sheltering frogs in every month because burrows occur 1 to 30 cm below the surface and in leaf litter.

Identification

This is a large, rotund, slow-moving frog with a strongly built body and powerful hind legs. It is usually found in or near forested streams, swamps and temporary pools, often after rain.

Adults have a dark brown-grey, steely blue-grey or black back and limbs, paler sides, a white to bluish-white belly and warty skin. Creamy white to yellow markings may occur along the flanks. The eyes are large, with a vertical pupil and silvery or silver-grey iris. The tympanum is large and distinct.

The fingers are unwebbed and the toes have only slight webbing at the base. There are no toe discs. Adult males have enlarged forearms and large black spines on the first three fingers during the breeding season.

Adult size: Males to 78 mm snout to vent length; females to 97 mm.

Body form: Large, rotund and powerfully built, with muscular hind limbs and enlarged foot areas adapted for burrowing.

Identification: Similar species

The species can be mistaken for the introduced Cane Toad, Rhinella marina. The Giant Burrowing Frog lacks the Cane Toad's large parotoid glands and has a vertical pupil rather than a horizontal pupil. It may also resemble Limnodynastes dumerilii and Limnodynastes terraereginae, but those species generally differ in the colour of the sides and thighs and lack a vertical pupil.

Identification: Calls and field signs

Males give a low-pitched, plaintive, owl-like call, described as a rapid succession of 'oop oop oop oop'. Calling males may call from burrows in creek banks, from burrows near breeding sites or from adjacent forest. Calling is often triggered by rain and may be limited or unpredictable, so absence of calls does not demonstrate absence of the species.

Tadpoles are large, plump and very dark grey-brown to black. Their blue-grey ventral surface helps distinguish them from other tadpoles. Burrows, frogs beneath leaf litter and eggs in foamy masses may be found around breeding pools, but adults and burrows can be difficult to detect in dense forest.

  • Do not rely on tracks, scats or eyeshine. These are not reliable field signs for this frog.
  • Use experienced nocturnal spotlighting and habitat assessment, with tadpole searches where suitable pools are present.
  • For survey work, use clean equipment and footwear between sites and follow a one bag, one frog approach to reduce disease transfer.

Distribution: Range and bioregions

The Giant Burrowing Frog occurs in coastal New South Wales and Victoria, including adjacent ranges and escarpments. Its distribution is divided into northern and southern population areas with a substantial gap between them.

In New South Wales, the northern population is largely associated with sandstone geology in the Sydney Basin and extends south to about Ulladulla. The southern population extends from north of Narooma through southern New South Wales to Walhalla in Victoria.

The species has been recorded from near sea level on the coast to almost 100 km inland along the Great Dividing Range, reaching about 1000 m above sea level. It occurs in the Sydney Basin, South East Coastal Plain, South East Corner, South Eastern Highlands and Australian Alps IBRA bioregions.

  • New South Wales: Sydney Basin, South East Coastal Plain, South East Corner and South Eastern Highlands.
  • Victoria: East and West Gippsland areas, including the range towards Walhalla.
  • The known distribution also overlaps the Australian Alps IBRA bioregion.

Distribution: Subpopulations and strongholds

Most records are from the northern population in the Sydney Basin. The southern population has sparse records across southern New South Wales and Victoria, with the Eden district identified as an area with more records than surrounding parts of the southern range.

Only one extant population had been located in Victoria at the time of the 2021 consultation document, although the number of Victorian populations was considered uncertain and possibly higher. The two broad population areas may represent separate taxa, but this taxonomic question remains unresolved.

  • Sydney Basin sandstone country is the main known concentration of records.
  • Eden is a notable area for records within the southern population.
  • Gippsland contains potential and known habitat, but formal reserve coverage of known Victorian records is limited.

Distribution: Population size and trend

A reliable total population estimate is not available. The species is difficult to detect because it burrows, is sparsely distributed and is usually detected at night after heavy rain. Historical accounts indicate local declines, especially where habitat has been cleared or fragmented.

The 2019 to 2020 fires affected an estimated 46 percent of the species' distribution range, but the population-level effect had not been fully measured. The consultation assessment assumed a reduction greater than 50 percent over the relevant period because of fire impacts and associated habitat effects.

Estimated extent of occurrence: About 80,000 square kilometres.

Atlas of Living Australia records: 1,326 records as at 23 April 2020, with most records from 2000 to 2009.

New South Wales reserve coverage: About 45 percent of the species' distribution in New South Wales occurs within the National Parks and Wildlife estate.

Population estimate: Not available.

Habitat: Overall habitat

The species depends on native vegetation, small watercourses and forest floor habitat. Protecting only a narrow stream buffer is not sufficient because most individuals occupy surrounding forest and heath away from the breeding water.

Habitat includes heath, woodland, open dry sclerophyll forest, wet and dry sclerophyll forest, montane sclerophyll woodland and montane riparian woodland. The species is associated with native vegetation and has not been recorded from cleared land. It occurs on a range of soils but is not associated with clay-based soils.

In the Sydney Basin, records are strongly associated with Hawkesbury Sandstone, upper topographic areas and ephemeral watercourses with gentle gradients. In the northern range, hanging swamps on sandstone shelves and sandy sandstone ridges supporting heath are important habitat types.

  • Retain native vegetation around streams, soaks, swamps, pools and drainage lines.
  • Treat forest and heath within at least 300 m of suitable breeding habitat as potential habitat.
  • Assess ridges, upper slopes, sandstone shelves, forest floor and nearby drainage lines, not only the stream channel.

Habitat: Vegetation and physical features

Suitable habitat generally has a complex native vegetation structure, shaded forest floor, leaf litter and relatively undisturbed soil that allows burrowing. Breeding areas are usually first or second order streams, ephemeral flowing streams with permanent pools, upland swamps, hanging swamp seepage lines and small temporary or permanent pools.

The species has also been recorded from artificial drainage ditches, road culverts and forest dams. Use of dams as breeding sites is uncertain in Victoria, so such sites should not be dismissed without assessment.

  • Avoid clearing or compacting shaded forest floor, understorey, leaf litter and soils used for burrows.
  • Maintain clean, slow or standing water with suitable pool habitat and stream bed structure.
  • Control erosion and sediment at roads, crossings, culverts, drains and construction areas.

Habitat: Elevation and climate

The species occurs from near sea level to almost 1000 m above sea level. It is associated with coastal and adjacent range climates, higher precipitation and milder temperatures in the Sydney Basin, and breeding activity linked to heavy rainfall.

There are no records from rainforest or ash-dominated montane forest in the consultation material. Reduced rainfall, increased temperatures and more frequent droughts are expected to reduce suitable habitat and breeding success.

Recorded elevation range: Near sea level to almost 1000 m above sea level.

Important weather trigger: Heavy rainfall commonly precedes movement and breeding activity.

Foraging habitat: Diet

Adults forage on the forest floor and around burrows in non-breeding habitat. The species is an invertebrate predator and spends most of its time away from breeding water.

Adults prefer ants but also eat other ground-dwelling invertebrates, including beetles, spiders, scorpions, centipedes and cockroaches. Moths have occasionally been found in stomach contents.

The diet of tadpoles is not known with certainty. Their mouthparts indicate that they probably graze algae and bacteria from pond bottoms or submerged objects.

  • Retain leaf litter, ground cover, woody debris and understorey that support terrestrial invertebrate prey.
  • Avoid pesticide, herbicide, fertiliser and sediment contamination near breeding and non-breeding habitat.

Foraging habitat: Foraging area

Individuals forage and shelter in forested non-breeding habitat, usually within 300 m of breeding sites. Radio-tracking and other studies have located frogs on mid and upper ridge slopes, 50 to 500 m from streams, and the survey guidelines describe activity areas of several hectares.

Typical management buffer: Native vegetation within 300 m of suitable breeding habitat is non-breeding habitat requiring assessment and protection.

Recorded distance from streams: 50 to 500 m in radio-tracking studies.

Activity area: Several hectares may be used by an individual, based on survey guideline information.

  • Include surrounding forest, heath, ridges and slopes in site impact assessments, even when no frogs are found at the waterbody.
  • Do not treat cleared or compacted strips between a breeding site and surrounding forest as equivalent to native habitat.

Breeding habitat: Breeding biology

Breeding follows heavy rain and occurs in small streams, soaks, swamps and temporary pools within native vegetation. Egg masses are laid out of the water or at the water margin, and tadpoles later develop in larger pools.

Breeding season: Mainly autumn. Calling and breeding activity can occur from spring to autumn, and calling has been recorded outside this period.

Movement to breeding sites: Adults move immediately before or after heavy rain and may occupy breeding sites for up to 10 days.

Egg mass: A thick, foamy mass laid in a burrow, crevice or under vegetation near a small pool. Clutches contain about 500 to 800 eggs in the conservation advice and 700 to 1,200 eggs in the consultation document.

Tadpole development: About 3 to 12 months. Late developing tadpoles may overwinter and complete development when temperatures rise.

Age at maturity: Estimated at about 3 years.

Lifespan: Thought to be up to 10 years or longer, but this has not been confirmed by a scientific study.

Gestation or incubation: No separate gestation period is reported. Eggs develop in a foamy terrestrial or marginal egg mass before hatching and flooding into pools.

Breeding habitat: Breeding site features

Breeding habitat is generally a soak or pool within a first or second order stream, an ephemeral flowing stream with permanent pools, a hanging swamp seepage line or a small pond. The species can also use permanent creeks, artificial drainage ditches and road culverts with rock or sand based substrates.

After rain, tadpoles may be washed from small egg-laying sites into larger pools where they complete development. Early pond drying can prevent metamorphosis, while sediment can fill crevices, cover tadpole food sources and remove egg-laying or refuge sites.

Typical stream size: Most typically streams with a bed width of up to 5 m, including second and third order streams in the NSW survey guide.

Reported breeding water conditions: Clear water, pH 4.3 to 6.5 and temperature 8.5 to 26.5 degrees Celsius are reported in the Australian Government survey guidelines.

  • Protect the full drainage path and connected pools, not only the pool where eggs or tadpoles are found.
  • Maintain natural flow, hydroperiod, water quality, stream bed crevices and shaded banks.
  • Prevent sediment, concrete washout, fuels, chemicals and nutrient-rich runoff from entering breeding water.
  • Schedule in-channel, culvert and bank works outside periods when eggs, tadpoles or recently moved adults are likely to be present, subject to project-specific ecological advice.

Sheltering habitat: Burrows and ground cover

The Giant Burrowing Frog shelters below the soil surface and in leaf litter rather than using tree hollows. Burrows can occur well away from breeding water and may be reused.

Individuals use a series of burrow sites below the soil surface or in leaf litter. Some burrows are used repeatedly. Burrows occur in shaded areas and may be located on forest floors, slopes, ridges and beside streams.

The species has been found buried at depths from 1 cm to 30 cm. Some individuals burrow in road environments, creating a direct risk during excavation, grading, trenching and road maintenance.

Recorded burrow depth: 1 to 30 cm below the soil surface.

Shelter type: Soil burrows and leaf litter, with no tree hollow, nest or roost requirement reported.

  • Retain undisturbed soil, leaf litter, understorey, shade and natural ground structure.
  • Avoid driving, stockpiling, trenching, grading and compacting soil within occupied or potential non-breeding habitat.
  • Inspect work areas within native vegetation and near breeding sites before soil disturbance, with a qualified ecologist and fauna spotter catcher where required.

Sheltering habitat: Habitat retention on work sites

The species spends more than 95 percent of its time in non-breeding habitat. A narrow riparian buffer may therefore leave most of the habitat used by frogs exposed to clearing, machinery, fire, logging and changes in shade or surface drainage.

  • Map breeding habitat and surrounding native vegetation within 300 m as separate but connected habitat components.
  • Keep temporary access tracks, laydown areas and spoil sites out of native vegetation and away from drainage lines where practicable.
  • Use amphibian hygiene procedures between sites and minimise handling during searches or relocations.

Threats: Clearing, fragmentation and construction

The main project risks are loss and fragmentation of native vegetation, disturbance of burrowing habitat, altered water flow and water quality, and vehicle mortality. Several threats can operate together, reducing breeding success and the ability of small populations to recover.

Clearing for urban development, agriculture and forestry is identified as the highest threat. Roads and cleared corridors fragment habitat, restrict movement and may reduce gene flow. Logging and construction can compact burrowing areas, remove understorey and reduce shade on the forest floor.

Clearing only the stream edge does not capture the main habitat risk because frogs spend most of their time in surrounding non-breeding forest and heath.

  • Avoid clearing native vegetation within 300 m of suitable breeding sites.
  • Fence and clearly mark retained habitat, breeding pools, drainage lines and no-go areas before machinery enters the site.
  • Keep vehicles, materials, spoil and temporary works out of shaded forest floor and known or potential burrowing habitat.
  • Treat road crossings, culverts and access tracks as potential movement and mortality points.

Threats: Roads and vehicle strike

Vehicle strike has been recorded on sealed and unsealed roads and may increase with traffic volume. Roads may also act as barriers. Frogs moving after rain are at particular risk because adults travel to and from breeding sites and may cross road surfaces or occupy road verges.

  • Avoid night-time vehicle movements through known habitat during and shortly after heavy rain where practicable.
  • Use low speeds, spot checks and fauna management controls on roads near breeding sites.
  • Inspect road verges, culverts and work areas for frogs before excavation or resurfacing.

Threats: Hydrology, sediment and pollution

Stormwater, water extraction, mining subsidence, road works, clearing and failed erosion controls can alter flow, hydroperiod and water quality. Consequences include premature pond drying, chemical contamination, altered pH, sediment deposition and loss of tadpole food or egg-laying crevices.

Fertilisers, fungicides, herbicides and pesticides applied near populations may enter habitat or harm frogs directly. Trampling by livestock, deer and feral animals can erode banks and increase sediment loads.

  • Keep clean water separate from dirty water and prevent sediment laden runoff from entering breeding habitat.
  • Maintain natural drainage, pool persistence and overland flow paths.
  • Stabilise exposed soil promptly and inspect controls after rainfall.
  • Prevent concrete washout, fuels, oils, chemicals and nutrient runoff from reaching streams, swamps and pools.

Threats: Fire, predators and disease

Inappropriate fire regimes can alter vegetation, ground cover, water temperature, sediment loads, nutrient loads and oxygenation. High intensity wildfire can remove shelter, increase predator access and deliver ash and sediment into streams. Feral cats and European Red Foxes are suspected predators, while Gambusia holbrooki and trout can eat eggs and tadpoles.

Chytrid fungus, Batrachochytrium dendrobatidis, has been detected in individuals and tadpoles. Disease risk is especially relevant when people, vehicles, nets or footwear move between frog sites.

2019 to 2020 fire overlap: An initial assessment estimated that 46 percent of the distribution range was affected.

Chytrid infection observation: At one site, 24 percent of late-stage tadpoles were reported as infected, although population-level effects remain uncertain.

  • Retain unburnt refuge patches, leaf litter and shaded ground cover where fire management allows.
  • Avoid introducing Gambusia or trout into temporary or permanent breeding water.
  • Manage feral cats and foxes in accordance with approved threat abatement and site management programs.
  • Clean and disinfect footwear, nets, equipment and vehicle tyres between sites, and use fresh gloves and separate bags for handled frogs or larvae.

Survey methodology: 1. Spotlighting and aural-visual surveys

Survey this species as a cryptic, fossorial frog with very low detection probability. Plan repeated night surveys in suitable breeding and non-breeding habitat, and treat a failure to detect frogs as inconclusive unless weather, reference-site activity and survey effort were suitable.

Survey native vegetation within 300 metres of suitable breeding habitat, including ephemeral streams, permanent pools, upland swamps, drainage lines and culverts.

Use aural-visual surveys from September to May, within one week of heavy rainfall. The NSW guide gives examples of suitable rainfall as more than 50 millimetres in 24 hours or more than 100 millimetres over three days.

Conduct surveys at night using hand-held spotlights while listening for the low-pitched, owl-like ‘oop oop oop oop’ call and searching the forest floor, stream margins, pools, banks and burrows.

Do not rely on call playback. This species has limited and unpredictable calling, and call playback is not considered effective for it.

For a 500 metre transect, complete 960 minutes of aural-visual survey over eight repeat surveys under suitable conditions. Cover suitable breeding habitat and adjacent native vegetation, not only the stream channel.

Where the project area permits, survey several square kilometres of suitable habitat on foot. Local-area road transects may extend up to 30 kilometres in suitable habitat, with repeated sections checked after about one hour.

Recommended survey window: September to May

Federal guideline calling period: February to April

Typical survey condition: Within one week of heavy rainfall

NSW effort for a 500 metre transect: 960 minutes over 8 repeat surveys

Survey methodology: 2. Tadpole and egg-mass searches

Search identified breeding pools and permanent or semi-permanent stream pools for tadpoles from February to May, preferably at night when tadpoles are most active.

Use a fine-meshed dip net and make multiple sweeps through suitable parts of each pool, including the water column, submerged vegetation and areas near banks.

For each 50 square metres of water surface, search for 10 minutes. The NSW guide specifies eight repeat searches for the 500 metre survey unit.

Look for large, dark tadpoles with a blue-grey ventral surface. Confirm identification with an appropriately experienced amphibian ecologist where required.

Search for foamy egg masses in burrows, crevices and under vegetation near small pools, but do not excavate burrows or disturb banks to find them.

Larval survey period: February to May

Tadpole search effort: 10 minutes per 50 square metres of water surface

NSW repeat effort: 8 searches for the 500 metre survey unit

Tadpole development: 3 to 12 months

Survey methodology: 3. Habitat and detection assessment

Map breeding habitat and non-breeding habitat separately. Include native vegetation within 300 metres of suitable breeding sites because frogs spend more than 95 percent of their time away from breeding habitat.

Inspect forest floor, leaf litter, shaded soil, banks, drainage structures and likely burrow sites. Individuals may use a series of burrows, some repeatedly, and may occur 50 to 500 metres from streams.

Record stream order, pool persistence, substrate, water quality, vegetation cover, shade, sediment, nearby roads and evidence of clearing, logging, grazing or fire.

Use a nearby reference site where the species is known to occur, preferably in the same drainage system and at a similar elevation. Check it during the planned survey period to confirm that frogs are active and detectable.

Allow for low detection. A NSW study reported a detection probability below 0.01 for an aural-visual survey of more than one hour, so absence must not be inferred from a single quiet survey.

Non-breeding habitat distance: Up to 300 metres from breeding sites

Reported radio-tracking distance: 50 to 500 metres from streams

Time outside breeding habitat: More than 95 percent

Published detection probability: Less than 0.01 for an aural-visual survey of more than one hour

Survey methodology: Minimum effort and reporting

Use the relevant state survey standard where the project is in NSW or Victoria, and obtain advice from the relevant state wildlife agency where the applicable effort is unclear.

Use experienced personnel who can identify the species and its call, distinguish its tadpoles and assess fossorial habitat.

Repeat surveys across suitable rainfall events and, where one season is inadequate, across more than one season or year.

Record survey dates, start and finish times, rainfall, temperature, wind, stream and pool conditions, transect lengths, area searched, repeat number, observers, reference-site results, methods and detection limitations.

Record all individuals, calls, tadpoles, egg masses, burrows and habitat observations with accurate GPS locations and photographs where safe.

Submit confirmed records and negative survey information, where required, to the relevant state wildlife database and the Atlas of Living Australia, and include records in the project environmental report.

Before habitat disturbance: Avoid and minimise habitat loss

Treat native forest, heath, sandstone swamps, small streams and pools as potential habitat. Protect the breeding site and the shaded terrestrial area around it, because clearing only a narrow stream buffer does not protect this frog’s main habitat.

  • Avoid clearing native vegetation around ephemeral streams, permanent pools, upland swamps, hanging swamps, drainage lines and culverts used by the species.
  • Retain native vegetation and minimise soil disturbance within 300 metres of known or suitable breeding habitat.
  • Retain shaded forest floor, leaf litter, loose soil, banks, burrows and natural drainage features used when frogs shelter and forage.
  • Maintain connectivity between breeding sites and surrounding forest, heath and woodland, particularly across ridges, slopes and stream catchments.
  • Avoid locating roads, access tracks, stockpiles, compounds and drainage outlets across movement routes or between breeding pools and retained forest.
  • Design the work footprint to avoid sediment delivery, changes to pool hydroperiod, altered runoff, pond drying and chemical contamination.

Before habitat disturbance: Approvals and work planning

  • Check the current EPBC Act listing before works start and refer the action if it may have a significant impact on this nationally listed species or its habitat.
  • Check state threatened-species requirements, development approvals, wildlife licences and fauna handling authorisations for the state or territory where work will occur.
  • Prepare a species-specific fauna management plan covering survey results, habitat maps, buffers, clearing limits, weather constraints, spotter catcher duties, stop-work triggers, hygiene and reporting.
  • Schedule vegetation and ground-disturbing work outside periods when frogs are likely to be moving or breeding after heavy rain, where the project programme allows.
  • Stage works so that retained breeding pools, forest refuges and movement routes remain available while each work area is cleared.
  • Obtain specialist advice before works near active breeding pools, egg masses, tadpoles, occupied burrows or contaminated sites with chytrid risk.

Before habitat disturbance: Site preparation

  • Complete the required pre-clearance survey under suitable wet-weather conditions before machinery enters the work area.
  • Mark no-go areas, breeding pools, stream margins, drainage lines, known burrows, egg masses, occupied refuge sites and the 300 metre non-breeding habitat zone where it applies.
  • Install exclusion fencing only where it will prevent entry into the work area without blocking movement between retained breeding and non-breeding habitat.
  • Keep sediment controls, clean-water diversions and spill controls away from pools and seepage lines, and inspect them before rainfall.
  • Clean and disinfect footwear, nets, spotlights, equipment, vehicles and other items before entering the site and between sampling areas to reduce chytrid transmission.

During habitat disturbance: Daily controls and machinery interface

Use a controlled, staged clearing process. The fauna spotter catcher must work ahead of machinery and have authority to pause work when a frog, occupied burrow or breeding habitat is found.

  • Hold a daily pre-start briefing covering mapped habitat, exclusion zones, weather, access routes, machinery limits and the fauna spotter catcher’s stop-work authority.
  • Inspect exclusion fencing, sediment controls, pool protection and access tracks before work starts and after substantial rain.
  • Keep machinery outside marked breeding habitat, retained vegetation and no-go areas unless the approved method specifically permits entry.
  • Clear in small stages towards retained habitat so animals can move away from machinery and the spotter catcher can inspect the next work area.
  • Use low ground pressure and avoid unnecessary traffic, grading, compaction and removal of leaf litter or topsoil in retained habitat.
  • Stop or postpone ground disturbance during heavy rain, rapid runoff or conditions that could wash sediment, fuel or chemicals into breeding pools.

During habitat disturbance: Finding and handling a frog

  • Stop machinery immediately if a giant burrowing frog, tadpole, egg mass, occupied burrow or suspected breeding site is found in the work area.
  • Keep workers, vehicles and machinery clear while the authorised fauna handler confirms the identification and assesses the location.
  • Do not excavate, probe or collapse a burrow, and do not handle an animal unless handling is necessary for its welfare, approved relocation or authorised fauna management.
  • Use clean, disinfected equipment and a fresh bag for each animal if handling is authorised, and minimise handling time and exposure to heat, drying and direct sun.
  • Relocate a healthy frog only under the approved fauna management plan, to nearby suitable retained habitat within the same local drainage and habitat system where practicable.
  • Do not move eggs or tadpoles unless the relevant wildlife authority and project approval expressly permit it and an amphibian ecologist has directed the method.
  • Transfer an injured frog to the nominated wildlife veterinarian or licensed wildlife carer, documenting the transfer and location of capture.

During habitat disturbance: Habitat features and stop-work triggers

  • Protect pools, stream beds, seepage lines, culverts, shaded banks, leaf litter, loose soil and burrows from direct disturbance.
  • Prevent sediment, concrete washout, fuel, oil, herbicides, fertilisers and other contaminants from entering breeding water.
  • Stop work and seek ecological direction if an occupied burrow, egg mass, tadpole concentration, repeated adult detections or unexpected breeding pool is found.
  • Stop work if exclusion fencing fails, machinery enters a no-go area, water quality deteriorates, a spill occurs or erosion threatens a breeding site.
  • Record all stop-work events, including the trigger, location, time, weather, action taken, person authorising recommencement and any animal outcome.

After habitat disturbance: Post-clearance inspection

Confirm that the approved footprint was cleared without leaving animals or breeding habitat at risk. Continue controls until disturbed areas are stable and retained habitat is functioning.

  • Complete a post-clearance inspection of the work area, access tracks, stockpile areas, pool margins and drainage structures before removing fauna controls.
  • Search disturbed ground, remaining vegetation, banks and exposed soil for frogs, burrows, egg masses and stranded tadpoles.
  • Check that no sediment, spoil, concrete, fuel or contaminated water has entered breeding pools or ephemeral streams.
  • Repair damaged exclusion fencing, erosion controls, banks, pools and retained vegetation immediately.
  • Map the final cleared area and any retained breeding or non-breeding habitat, including changes from the approved footprint.

After habitat disturbance: Monitoring and reporting

  • Monitor retained breeding pools and adjacent forest after major rainfall and during the next suitable breeding period where the project has altered habitat, drainage or connectivity.
  • Use the same locations and methods as the pre-work surveys so changes in detections, pool persistence, tadpole development and habitat condition can be assessed.
  • Report all captures, injuries, deaths, relocations, breeding observations, sediment incidents, stop-work events and non-compliances to the project ecologist and regulator where required.
  • Update the fauna management plan if monitoring shows altered hydroperiods, failed recruitment, loss of shade, increased vehicle mortality or new predator pressure.
  • Submit confirmed species records and relevant monitoring results to the relevant state wildlife database.

After habitat disturbance: Offsets and residual impacts

  • Assess residual loss of breeding habitat, non-breeding habitat, movement routes and ecological connectivity under the applicable Commonwealth and state offset requirements.
  • Do not treat a narrow stream buffer as an adequate substitute for the forested non-breeding habitat used by this species.
  • Document why impacts could not be avoided, the area and condition of affected habitat, the proposed offset or rehabilitation action and the measures used to protect retained habitat.

Rehabilitation actions: Restore terrestrial habitat

Rehabilitation should restore a connected forest and stream system, not only a watercourse edge. The aim is to provide shaded burrowing habitat, persistent breeding pools, clean runoff and safe movement between breeding and non-breeding areas.

  • Re-establish locally native heath, woodland or open dry sclerophyll forest appropriate to the site, using local provenance species where available.
  • Restore a complex understorey and shaded forest floor with native groundcover, leaf litter and natural soil structure.
  • Reinstate suitable loose soil and undisturbed banks for burrowing, and avoid compaction from vehicles, stock or maintenance equipment.
  • Retain and replace naturally occurring logs, rocks, leaf litter and other ground refuges where they have been removed, without placing material in active pools or blocking drainage.
  • Reconnect rehabilitated areas to retained native vegetation and breeding sites across the full area used by the species, including habitat up to 300 metres from breeding sites.

Rehabilitation actions: Restore breeding habitat and water quality

  • Reinstate shallow, clean-water pools and low-order stream features with natural rock or sand substrates where these were removed or damaged.
  • Design drainage and rehabilitation works to maintain suitable wet and dry periods and prevent premature pool drying during the 3 to 12 month tadpole period.
  • Stabilise bare soil and stream banks with native vegetation and erosion controls that do not reduce pool habitat or obstruct frog movement.
  • Prevent sediment, ash, nutrients, pesticides, herbicides, fuel and other pollutants from entering pools, seepage lines and streams.
  • Do not make ephemeral breeding streams permanently wet or introduce fish into pools, because introduced fish can eat eggs and tadpoles and may persist if temporary pools become permanent.

Rehabilitation actions: Manage threats and measure success

  • Control weeds and prevent livestock, deer and feral animals from trampling pool margins, degrading vegetation and increasing sediment loads.
  • Manage feral cats and foxes in accordance with approved threat-management programs, particularly after fire or major habitat disturbance when frogs may be more exposed.
  • Use a fire regime that maintains native vegetation structure and water quality, and avoid high-intensity or excessively frequent fire near breeding habitat.
  • Monitor vegetation cover, soil compaction, burrow availability, pool hydroperiod, sediment, water quality, tadpole development, metamorph recruitment and adult detections.
  • Set success measures before rehabilitation starts and continue monitoring through at least the next suitable breeding periods, with corrective works if pools dry early, sediment accumulates or native cover fails to establish.

Sources