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Spotted Tree Frog (Dryopsophus spenceri)

The Spotted Tree Frog is a medium-sized stream-breeding frog restricted to rocky, permanent upland streams in the central highlands of Victoria and the upper Murray catchment of New South Wales. It is listed as Critically Endangered in the supplied project information and is highly sensitive to sediment, altered flows, introduced fish, chytrid fungus and disturbance of riparian and in-stream habitat, so even works near apparently suitable streams require careful survey and controls.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Breeding season

Spotted Tree Frogs use rocky streams from about October to May. Males call from late October to late December, eggs are laid from late November to December, and metamorphosis usually occurs from mid-February to late March. Plan clearing, stream works and dewatering to avoid October to April, including periods when adults are not visible.

Reproductive mode: Egg laying. Eggs are deposited as a single cluster in submerged rock crevices or beneath large in-stream boulders.

Clutch size: 278 to 928 eggs, with mean clutch size about 860 at lower elevations and about 482 at higher elevations.

Incubation: Not recorded.

Size at hatching or birth: Not recorded.

Age at maturity: Males may mature at 2 to 3 years. Females may mature from 3 years, with most taking about 4 years at some sites and 5 to 6 years at a higher-elevation site.

Nest or egg sites: Under large in-stream boulders or in submerged rock crevices in permanent rocky streams.

Breeding frequency: One breeding period per year is recorded. The species produces one egg cluster per spawning event.

Confirm timing locally with the relevant state agency and current survey guidance, and adjust survey and works timing for rainfall, temperature, elevation and stream-flow conditions.

  • Calling: Males call from late October to late December. Calling is usually strongest in November and December, although timing can vary with temperature, elevation, rainfall and stream conditions.
  • Egg laying: Eggs are laid from late November to the end of December. The egg cluster is attached to submerged rock crevices or placed beneath large in-stream boulders.
  • Tadpoles: Tadpoles develop in shallow pools and shallow stream margins after spawning. The documented cycle places larval development mainly from summer into early autumn, with no evidence that tadpoles overwinter in the stream.
  • Active period: The stream environment is used from approximately October to May. Adults and juveniles generally make short movements along the stream and show high site fidelity.
  • Winter inactivity: The species uses the stream environment from about October to May, but winter refuges have not been located. Treat June to September as a likely lower surface activity period, not as confirmed absence, and retain connected riparian habitat until local assessment is completed.
  • Highest clearing risk: Clearing, sediment release, flow changes and dewatering can affect adults, eggs and tadpoles from October to April. Risk is highest in late October to December during calling and egg laying, and in February and March when tadpoles metamorphose.

Identification

The Spotted Tree Frog is a medium-sized, warty tree frog associated with rocky permanent streams. It is usually found on rocks, stream banks or riparian vegetation, rather than in open terrestrial habitat.

Adults are usually 40 to 55 mm long, with females reaching up to 61 mm and males about 50 mm. The dorsal colour is variable, ranging from pale brown or grey to bright green or olive-grey, often with darker brown or olive spots. The back has numerous small raised warts. The underside is pale and granular, often with pale orange towards the rear and on the underside of the hind limbs.

Snout to vent length: 40 to 55 mm typically; females up to 61 mm and males about 50 mm.

Adult weight: About 13 g.

  • The head is broad, with a distinct fold above the indistinct tympanum.
  • The pupil is horizontal, and a green patch is often present below the eye.
  • The fingers have basal webbing, the toes are fully webbed, and the toepads are wider than the toes.
  • The tadpole is free swimming, with an elongated flattened body, a moderately thick tail and a rounded tail tip.

Identification: Call and field detection

The advertisement call has two parts: a drawn-out 'eeerrrrrrrr' followed by a series of shorter 'crer, crer, crer, crer' notes. Calling is most likely when weather conditions are suitable between late October and late December.

Adults may be active by day or night, depending on the site. Juveniles are mostly diurnal. Frogs often bask in direct sunlight on rocks beside moving water and may jump into the stream when approached or disturbed.

  • Search exposed rocks, loose rock banks, riffles, cascades and adjacent stream-side vegetation.
  • Listen for the two-part call during the late October to late December calling period.
  • Inspect rock crevices and the undersides of large in-stream boulders for eggs, but avoid moving rocks or entering the stream without appropriate controls.
  • Do not rely on pitfall trapping as a primary method, because the species is a stream-associated tree frog and pitfall trapping is generally unsuitable for tree frogs.

Identification: Similar frogs and field signs

The combination of a warty back, variable pale brown to olive or green colour, horizontal pupil, green patch below the eye, fully webbed toes and association with rocky permanent streams helps separate the species from other stream frogs. The Eastern Stony Creek Frog can also occupy permanent rocky rivers, but the Spotted Tree Frog has wider toepads, a more distinctly warty back and the characteristic two-part call described above.

  • No tracks, scats, sloughs or eyeshine should be expected as reliable field signs for this species.
  • Useful evidence includes adults, juveniles, the two-part advertisement call, eggs in rock crevices and tadpoles in shallow pools or shallow stream margins.
  • Record the exact stream reach, bank, rock feature, call location and photographs where possible, because populations are patchy and individuals show high site fidelity.

Distribution: States and regions

The species is endemic to south-eastern Australia and has a highly fragmented distribution along the north-west side of the Great Dividing Range. The known range extends from the central highlands of Victoria to the Kosciuszko area of New South Wales, within the Australian Alps and adjoining south-eastern temperate forest and woodland regions.

In Victoria, the species occurs mainly in the central and eastern highlands, including catchments draining the Great Dividing Range. In New South Wales, it is associated with the upper Murray catchment and Kosciuszko National Park.

The supplied sources place the species within the Australian Alps montane grasslands, south-east Australian temperate forests and adjoining Murray-Darling woodlands and mallee ecological regions. Its actual occupied habitat is narrower than these broad regional groupings and is concentrated on rocky upland streams.

  • Victoria: central highlands and eastern Victorian stream catchments.
  • New South Wales: the upper Murray catchment, including a site in Kosciuszko National Park.
  • Known stream systems include the Howqua, Snowy, Lightning, Goulburn, Black, Jamieson, Wongungarra, Big, Taponga, Still, White, Bundarra, Wheeler, West Kiewa, Indi, Bogong, Murray and Snake Creek systems, although the status of individual stream populations varies.

Distribution: Subpopulations and trend

The recovery plan reported 13 discrete extant populations in 1998, 11 in Victoria and two in New South Wales, distributed across 21 streams or stream reaches. It also recorded local disappearances and presumed extinctions in several historical streams. More recent NSW information describes one known NSW location in Kosciuszko National Park and a conservation program based on captive breeding, translocation and habitat management.

Recovery plan population estimate: 13 discrete populations in 1998, comprising 11 in Victoria and two in New South Wales.

Historical stream status: Four historical populations were considered presumed extinct in the recovery plan, and frogs had disappeared from historical sites on several other streams.

Estimated adults in selected Victorian populations: Approximately 390 to 1,550 adults in the listed populations, with estimates for individual streams or stream groups including about 390, 490, 640, 670, 870, 950, 1,090, 1,100 and 1,550 adults.

Recent NSW recovery observation: More than 200 frogs of juvenile and adult age classes were reported at a recovering translocated site after a 2022 release.

  • The species has undergone a major contraction in distribution and abundance.
  • Populations are isolated and genetically subdivided between stream systems, so natural recolonisation of nearby streams is considered unlikely.
  • A translocated NSW population initially increased and expanded for six years, then was severely affected by the 2019 to 2020 wildfires and a subsequent chytrid outbreak. Monitoring after a 2022 release found more than 200 frogs across juveniles and adults at the recovering site.

Habitat: Stream and catchment setting

Spotted Tree Frogs occupy naturally vegetated, rocky, swift-flowing upland streams in dissected mountainous country. Habitat use is concentrated around stream microhabitats with loose rocks, rocky banks, riffles, rapids, cascades and shallow pools, together with adjacent riparian vegetation.

Occupied streams occur from about 200 to 1,110 m above sea level. Most sites are in forested or naturally vegetated mountainous catchments with limited access and relatively low disturbance.

The species is associated with permanent or persistently flowing rivers and streams. Tadpoles develop in the stream, particularly in shallow pools or shallow margins, so stream condition and catchment processes directly affect recruitment.

Elevation: About 200 to 1,110 m above sea level.

Stream type: Naturally vegetated, rocky, swift-flowing upland streams and permanent rivers.

  • Retain natural stream channels, riffles, cascades, shallow pools and loose rock substrates.
  • Protect the full streamside zone and upstream catchment from sediment, chemical contamination and rapid changes in flow.
  • Treat tributaries, confluences and apparently unoccupied reaches within an occupied catchment as potentially relevant habitat where suitable rocky stream features remain.

Habitat: Vegetation and structure

Adjacent stream-side vegetation provides shelter and basking sites. The recovery plan does not identify a single required plant community, but records the species in naturally vegetated mountainous catchments and in forest areas. Riparian vegetation also helps maintain bank stability, shade, cover and stream condition.

  • Retain overhanging and stream-edge vegetation, native ground cover, leaf litter and stable banks.
  • Avoid clearing or stockpiling material on rocky banks, riffles, cascades or shallow stream margins.
  • Prevent weed invasion, grazing damage, inappropriate fire effects and timber or road works from altering the riparian structure.

Foraging habitat: Diet and feeding sites

The Spotted Tree Frog is a carnivore that eats invertebrates. The supplied sources provide no prey list or quantified feeding range, but adults and juveniles use the stream edge, rocks and nearby riparian vegetation for activity and likely foraging.

The species is recorded as feeding on invertebrates. Adults use rocks, rocky banks and stream-side vegetation, and may remain close to the stream during the active season. Juveniles are mostly diurnal and may forage on or beside the stream.

Diet: Carnivorous, mainly invertebrates.

Known seasonal stream use: The stream environment is used from approximately October to May.

  • Retain native riparian vegetation, ground cover, loose rocks and moist stream margins that support invertebrate prey.
  • Avoid broad clearing of vegetation adjacent to occupied streams, even where no breeding rocks or eggs are present.
  • Prevent sediment, herbicide, weed invasion and altered flow from reducing the quality of the stream edge and associated prey habitat.

Foraging habitat: Foraging range

The full non-breeding habitat used away from streams is not known. Mark-recapture and radio-tracking data show strong site fidelity and generally short movements during the breeding season, indicating that foraging habitat close to the occupied stream is important.

Average seasonal net movement: Less than 40 m for adults and juveniles at monitored sites.

Maximum recorded movement: 347 m.

Radio-tracked movements: Most movements along the stream were less than 10 m over 4 to 5 weeks, and few frogs moved more than 100 m in that period.

  • Survey and assess both the stream channel and adjacent riparian habitat rather than treating the watercourse alone as habitat.
  • Keep disturbance buffers continuous along the occupied reach where practicable, because individuals may move along the stream and use nearby shelter and basking sites.
  • Do not assume that unoccupied riparian vegetation is redundant without considering seasonal use and the limited evidence available for winter refuges.

Breeding habitat: Breeding sites

Breeding occurs in rocky permanent streams during spring and early summer. Eggs are placed in protected rock crevices or beneath large in-stream boulders, and tadpoles remain in shallow stream habitats until metamorphosis.

Males call from rocks within or along the stream edge. Eggs are deposited under large in-stream boulders or in rock crevices. Tadpoles develop in shallow pools or shallow stream margins and metamorphose in late summer to early autumn.

Breeding habitat depends on stable flow, clean water, suitable submerged rock crevices, shallow margins and low sediment loads. Increased sediment can reduce egg deposition sites, reduce algae and food availability, slow tadpole growth and delay metamorphosis.

  • Protect large in-stream boulders, submerged rock crevices, riffles, cascades, shallow pools and shallow margins.
  • Maintain natural flow and avoid sudden drawdown, diversion, impoundment or high sediment inputs during the breeding and tadpole period.
  • Keep introduced trout and other exotic fish out of breeding reaches where management arrangements allow, because trout can prey heavily on tadpoles.

Breeding habitat: Breeding biology

Recruitment is highly variable between years and populations. Egg and tadpole survival strongly influence population size and extinction risk, so works that affect the stream during spring, summer or autumn can affect recruitment even when adult frogs are not seen.

Breeding season: Calling from late October to late December; oviposition from late November to the end of December.

Clutch size: 278 to 928 eggs; mean clutch size is higher in lower-elevation populations, about 860 compared with about 482 at higher elevations.

Egg and larval habitat: Eggs under large in-stream boulders or in rock crevices; tadpoles in the stream, especially shallow pools and shallow margins.

Metamorphosis: Usually from mid-February to late March.

Age at maturity: Males may mature at 2 to 3 years. Females may mature from 3 years, with most taking about 4 years at some sites and 5 to 6 years at a higher-elevation site.

Longevity: The oldest individual detected in the recovery research was a 13-year-old female; some monitored frogs lived beyond 9 years.

Development: There is no evidence that tadpoles overwinter in the stream.

Sheltering habitat: Known refuges and basking sites

Shelter is concentrated in and beside rocky streams. Adults use loose rocks, rocky banks, stream-side vegetation and probably off-stream refuges outside the October to May stream-use period, but the full winter habitat is not known.

Adults are commonly associated with loose rock substrates, rocky banks, riffles, rapids and cascades. Adjacent stream-side vegetation is used for sheltering and basking. Frogs may bask in direct sunlight on warm rocks beside moving water and enter the stream when disturbed.

Known refuge feature: Loose rocks, rocky banks, riffles, rapids, cascades and adjacent stream-side vegetation.

Egg refuge feature: Rock crevices and the underside of large in-stream boulders.

  • Retain loose rocks, stable boulders, rock crevices, under-bank cover and stream-edge vegetation.
  • Do not remove, relocate or bury rocks in occupied or potentially occupied stream reaches.
  • Keep machinery, temporary crossings, access tracks, spoil and stored materials away from rocky banks and riparian cover.

Sheltering habitat: Seasonal shelter and disturbance

The species uses the stream environment from approximately October to May, but the habitats used at other times, including winter refuges, have not been determined. Radio tracking has documented short-distance use of the stream environment during periods of one to four weeks, but frogs have not been tracked through autumn to their overwintering refugia.

  • Treat connected riparian habitat outside the immediate channel as potentially relevant until seasonal survey and habitat assessment show otherwise.
  • Avoid assuming that absence from exposed stream rocks means absence from the site, particularly outside the active season or during unsuitable weather.
  • Use disease hygiene procedures between stream reaches and avoid moving wet equipment, water, rocks or sediment between frog habitats.

Threats: Clearing, construction and sediment

The main risks are processes that change stream flow, water quality, sediment loads, riparian cover or aquatic predation. The species also faces chytrid disease, fire impacts and extinction risk from small, isolated populations.

Roading, timber harvesting, dredging, recreation, grazing, weed invasion, herbicides, mining and other works can damage stream and riparian habitat. Increased sediment can bury egg deposition sites, reduce tadpole food, slow growth and delay metamorphosis.

Clearing and fragmentation are particularly serious because populations have high site fidelity, limited movement and little chance of natural recolonisation after local extinction.

  • Avoid clearing naturally vegetated riparian zones, rocky banks and streamside basking and shelter sites.
  • Design crossings and access routes to avoid occupied stream reaches, riffles, cascades, boulders and shallow margins.
  • Use effective erosion and sediment controls before ground disturbance and maintain them through construction and rehabilitation.
  • Prevent concrete washout, fuels, herbicides, sewage, contaminated water and other toxic substances from entering streams.
  • Rehabilitate roads and crossings that deliver sediment to occupied catchments.

Threats: Hydrology and fire

Changes in stream flow can affect egg viability, tadpole survival and the availability of shallow breeding habitat. Impoundments, water regulation, diversions and altered catchment runoff can therefore affect recruitment.

Wildfire can directly remove riparian cover and alter stream condition. A translocated population was severely affected by the 2019 to 2020 wildfires, followed by a chytrid outbreak.

  • Maintain natural flow timing, depth variation and shallow margins during spring, summer and autumn.
  • Avoid rapid changes in flow or dewatering near breeding reaches.
  • Plan fire prevention, suppression access and post-fire erosion controls to avoid damage to rocky streams and riparian habitat.
  • Inspect occupied catchments after fire for sediment pulses, bank instability, loss of cover and disease risk.

Threats: Predators and disease

Introduced trout can prey heavily on Spotted Tree Frog tadpoles and may substantially reduce recruitment. Chytrid fungus has been detected in several populations and has been associated with severe declines, although the precise contribution of infection can vary between sites and conditions.

Introduced fish risk: Trout preyed heavily on Spotted Tree Frog tadpoles in trials and enclosure experiments indicated potential for significant effects on tadpole populations.

Disease evidence: Chytrid fungus was detected in frogs from Bogong Creek, Taponga River, Snake Creek and the Goulburn River, with later NSW recovery work also reporting chytrid impacts.

  • Prevent the introduction or spread of non-native fish into occupied or potentially occupied streams.
  • Do not transfer fish, water, sediment, rocks, aquatic plants or wet equipment between catchments without suitable decontamination.
  • Apply current amphibian disease hygiene protocols during surveys, handling, translocation and construction monitoring.
  • Report sick or dead frogs through the relevant state conservation program and retain evidence only under approved disease investigation procedures.

Threats: Population isolation

The remaining populations are small, patchy and genetically subdivided between stream systems. Variable recruitment, high juvenile mortality and stochastic events increase the risk that a local disturbance will cause extinction, with little prospect of natural recolonisation.

  • Treat every known population and occupied stream reach as a separate conservation unit unless current advice states otherwise.
  • Do not use a nearby unoccupied stream as an assumed replacement habitat without approved habitat assessment and translocation planning.
  • Retain connectivity within each occupied catchment and protect both breeding reaches and adjacent shelter and foraging habitat.

Survey methodology: 1. Habitat assessment and diurnal searches

Survey this species as a stream-dwelling frog associated with permanent, rocky, fast-flowing upland streams and adjacent riparian habitat. Use several methods because adults may be present without calling, and eggs and tadpoles occupy different microhabitats.

Map permanent rivers, rocky banks, riffles, cascades, shallow pools, loose rock substrates, large in-stream boulders and adjoining naturally vegetated banks before selecting survey sites.

Search stream margins, rocks and riparian vegetation for basking, sheltering and foraging frogs, and inspect suitable egg-laying crevices without moving large rocks or entering unsafe flows.

Record stream condition, flow, sediment, riparian vegetation, weeds, introduced fish, access tracks and nearby disturbance because these features affect habitat suitability and recruitment.

Known breeding habitat: Permanent, rocky, swift-flowing upland streams, with eggs in rock crevices or beneath large in-stream boulders.

Known active period in streams: October to May.

  • Prioritise naturally vegetated, rocky streams between 200 and 1110 metres above sea level, while recognising that the full range of non-breeding habitat is not known.
  • Treat apparently suitable habitat as occupied until targeted surveys and appropriate advice indicate otherwise, particularly where the project is within the known range in central Victoria or the upper Murray catchment of New South Wales.

Survey methodology: 2. Nocturnal spotlighting and visual encounter surveys

Conduct repeated searches along stream banks, exposed rocks, riffles, cascades and adjoining riparian vegetation during the active period, with particular attention to mid spring through early summer.

Search both sides of the stream where safe, and record the start and finish time, weather, water level, stream reach searched, observers and all frogs detected.

Use direct observation and spotlighting as complementary methods because the species may be active by day or night, and juveniles are mostly diurnal.

Do not treat a negative night as evidence of absence, because the species has a patchy distribution, high site fidelity and low movement during the breeding season.

Adult size: Approximately 40 to 55 mm in the NSW field guide; females may reach 61 mm and males 50 mm in the recovery plan.

Recorded movement: Average net movement during one season was less than 40 metres, with a maximum recorded movement of 347 metres.

  • Use experienced observers familiar with the species’ warty pale grey or brown appearance, darker spots, horizontal pupil, green patch under the eye and fully webbed toes.
  • Record the exact location of every detection and photograph or describe the animal where this can be done without handling.

Survey methodology: 3. Call surveys and automated recording

Undertake call surveys from late October to late December, when calling activity is recorded, and include suitable weather conditions during the breeding period.

Listen from stream banks and rocky calling sites, especially where males can call from rocks within or beside the stream.

Use audio strip transects, static call stations or automated recorders in accordance with the survey guidelines, and document recorder locations, deployment dates, weather and listening periods.

Use call records with visual and habitat evidence because call surveys detect calling males only and will miss females, juveniles and non-calling males.

Calling period: Late October to late December, subject to seasonal and site variation.

Call structure: A two-part call, an extended note followed by repeated shorter notes.

  • Identify the two-part call as an extended ‘eeerrrrrrrr’ or ‘eeerrrrrrrr’ followed by repeated ‘crer’ notes, and retain recordings for expert verification where identification is uncertain.
  • Repeat surveys across suitable nights and, where one season cannot provide adequate detection probability, consider surveys over multiple years as advised by the survey guidelines.

Survey methodology: 4. Egg and larval surveys

Inspect submerged rock crevices, spaces beneath large boulders, shallow pools and shallow stream margins during the breeding and larval development period.

Search for egg masses from late November to the end of December, when oviposition has been recorded.

Sample or observe tadpoles only under an approved method that avoids damage to egg-laying sites and stream habitat, and use expert identification because larvae can be difficult to identify to species.

Record water depth, flow, substrate, sediment, algae, shelter and introduced fish at each egg or tadpole detection.

Oviposition period: Late November to the end of December.

Larval development: Summer and autumn, with metamorphosis recorded from mid February to late March.

Clutch size: 278 to 928 eggs, with reported means of 860 at low altitude and 482 at high altitude.

  • Use egg mass surveys to extend detection beyond calling periods, but recognise that eggs may be concealed in rock crevices.
  • Use larval sampling as an additional method, not as a substitute for adult and call surveys, because sampling is labour intensive and larvae may be difficult to identify.

Survey methodology: Minimum effort and reporting

  • Obtain a project-specific survey design from a suitably qualified herpetologist where the proposal may affect suitable stream or riparian habitat, because the supplied guidance does not provide a single species-specific minimum number of nights, hours or transect length.
  • Schedule surveys to cover the active and calling periods, and use more than one survey method where detection of adults, eggs and tadpoles is required.
  • Survey all suitable stream reaches and adjoining habitat within the disturbance footprint and any areas proposed for relocation or rehabilitation.
  • Use multiple years of survey where one year of data is unlikely to detect the species or resolve seasonal conditions, as recommended in the survey guidelines.
  • Record survey effort, dates, start and finish times, observers, weather, stream flow, methods, searched area or reach, detection results and photographs or recordings.
  • Submit confirmed records and negative survey results, where requested, to the relevant state or territory wildlife database and provide records to the project approval authority.
  • Report any suspected chytrid infection or unusual mortality through the relevant wildlife disease and threatened species channels.

Before habitat disturbance: Avoid and minimise

Avoid disturbing occupied streams and their adjoining riparian habitat wherever practicable. The species has a fragmented distribution, strong site fidelity and little prospect of natural recolonisation after local extinction.

  • Redesign the footprint to retain permanent rocky streams, riffles, cascades, shallow pools, large boulders, rocky banks and naturally vegetated stream margins.
  • Keep construction plant, stockpiles, spoil, fuels, concrete washout and sediment controls out of the stream and riparian habitat.
  • Maintain movement and dispersal along the stream and between occupied reaches, because most recorded movements are short and populations are isolated between stream systems.
  • Prevent changes to natural flow, water quality, temperature, sediment load and streambed structure.
  • Avoid removing basking, sheltering and foraging sites adjacent to the stream, including loose rocks, stable banks and riparian vegetation.

Before habitat disturbance: Approvals and planning

  • Confirm the current national conservation listing and determine whether the action requires an EPBC Act referral or approval before works commence.
  • Check state or territory threatened species, wildlife handling, scientific collection, transport, translocation, fisheries, waterway and national park requirements for the project location.
  • Prepare a threatened fauna management plan that identifies mapped habitat, exclusion areas, survey results, authorised personnel, hygiene controls, stop-work triggers, incident contacts and reporting requirements.
  • Plan works outside the main breeding and larval period where practicable, particularly late November to late March, and obtain ecological advice before working in the October to May active period.
  • Stage works so that retained stream habitat remains connected and protected while each work area is cleared and stabilised.

Before habitat disturbance: Site preparation

  • Complete targeted pre-clearance surveys immediately before works in suitable stream and riparian habitat, using the approved combination of visual, call, egg and larval methods.
  • Mark no-go areas, stream buffers, egg-laying rocks, shallow pools, riparian vegetation and access limits on plans and on the ground.
  • Install exclusion fencing where it can prevent entry into retained stream habitat, and inspect the fencing before and during works.
  • Brief all workers on the species’ appearance, habitat, call, disease hygiene, reporting process and stop-work requirements.
  • Provide a clean, dry, secure holding container and access to an authorised fauna spotter catcher where handling may be required.

During habitat disturbance: Daily controls and spotter catcher duties

Treat any frog, egg mass, tadpole or suitable occupied stream reach as a live environmental constraint. Keep machinery away from water and stop work when the approved controls cannot be maintained.

  • Inspect exclusion fencing, stream protection measures, sediment controls and access routes before work each day.
  • Have the fauna spotter catcher inspect the active work area and adjacent stream margin before machinery enters, and maintain communication with the operator throughout the task.
  • Use a spotter catcher who is authorised under the relevant state or territory requirements to handle, hold or relocate this species.
  • Keep plant movements slow and controlled near stream banks, rocks, riparian vegetation and water, and prevent spoil, sediment, fuel, concrete and dirty water from entering the stream.
  • Apply approved amphibian hygiene and chytrid controls between catchments, work areas, equipment and animals.

During habitat disturbance: Habitat features and animals

Recorded site fidelity: Many individuals remained on monitoring transects after two years, and most radio-tracked movements were less than 10 metres over 4 to 5 weeks.

  • Do not move large in-stream boulders, loose rocks, egg-laying substrates or streambed material unless the approved method specifically requires it and an authorised ecologist is present.
  • Treat any egg mass, tadpole concentration, basking frog, sheltering frog or dead frog as a recordable fauna event and protect the location from further disturbance.
  • If a frog is found, stop the immediate task, keep people and machinery clear, and allow the authorised fauna handler to assess and manage it.
  • Relocate a live frog only where authorised and only to suitable nearby retained habitat identified in the fauna management plan, because the species shows high site fidelity and isolated populations have little natural recolonisation capacity.
  • Do not undertake an unapproved translocation between catchments or populations; follow the approved translocation or reintroduction protocol where one applies.

During habitat disturbance: Stop work, injury and records

  • Stop work and establish an exclusion area if a spotted tree frog, egg mass, tadpole aggregation, unexplained frog mortality or suspected disease is found within the work area.
  • Stop work if sediment, altered flow, contaminated water, fuel, concrete or machinery access is affecting the stream or retained riparian habitat.
  • Place an injured frog in a clean, secure, appropriately ventilated container only under the fauna management plan and by authorised personnel, and arrange prompt assessment by an approved wildlife carer or veterinarian.
  • Do not release an injured or captive-held frog without advice from the responsible wildlife authority or project ecologist.
  • Record the date, time, exact location, animal life stage, condition, photographs, handling, destination, disease observations, people involved, machinery activity and corrective action.
  • Notify the project environmental officer, approval holder and relevant wildlife authority of any mortality, disease concern, unauthorised habitat impact or release outside the approved method.

After habitat disturbance: Immediate checks

Post-work checks must confirm that retained stream habitat remains usable and that controls have prevented sediment, flow and water-quality impacts. Monitoring should be linked to the species’ known recruitment risks and to the approval conditions.

  • Inspect the full work area, stream margin, access routes and downstream reach after each clearance or construction stage.
  • Search disturbed and retained habitat for injured, trapped or stranded frogs, egg masses and tadpoles before removing fauna controls.
  • Check that no rocks, boulders, riparian vegetation, shallow pools or stream margins have been damaged outside the approved footprint.
  • Repair erosion, sediment controls, barriers and drainage failures immediately, and prevent further work until the environmental officer accepts the controls.

After habitat disturbance: Monitoring and adaptive management

Recruitment sensitivity: The recovery plan identifies larval recruitment as a particularly important determinant of population size and extinction probability.

  • Continue visual, call, egg and larval monitoring at affected and retained reaches during the active period, with effort and timing set by the approved monitoring plan.
  • Include recruitment, metamorphosis, adult presence, disease observations, stream flow, sediment, water quality, introduced fish and riparian condition in monitoring records.
  • Compare results with pre-work data and investigate reduced calling, adult detections, egg survival, tadpole survival or recruitment.
  • Use monitoring results to change sediment controls, access arrangements, riparian protection, fish management or work staging before further disturbance.

After habitat disturbance: Completion and reporting

  • Provide the approval authority with survey, handling, mortality, disease, rehabilitation and monitoring records in the required format and timeframe.
  • Maintain exclusion fencing and stream protection controls until the site is stable and the project ecologist confirms that removal will not expose frogs or habitat to renewed harm.
  • Report confirmed records, mortalities and any changed distribution information to the relevant state or territory wildlife database.
  • Implement approved offsets or compensatory habitat measures where residual impacts remain after avoidance and mitigation.

Rehabilitation actions: Restore stream and riparian habitat

Rehabilitation should recreate the permanent, rocky, vegetated stream conditions used for breeding, shelter and basking. Prioritise sediment and flow control, streambed structure, riparian cover and protection from introduced fish and weeds.

  • Re-establish native riparian vegetation suited to the local stream and catchment, using locally appropriate species approved by the restoration ecologist.
  • Stabilise disturbed banks and drainage lines without smothering rocky stream habitat or filling egg-laying crevices with sediment.
  • Reinstate natural-looking riffles, cascades, shallow pools, rocky margins and stable boulder habitat where these features were lawfully disturbed and the approved design requires reinstatement.
  • Retain or replace suitable loose rocks and large boulders only under an ecologist-approved method that does not alter flow or damage existing egg masses.
  • Prevent sediment, altered water quality and altered flow from reaching the stream during establishment and maintenance.

Rehabilitation actions: Manage weeds, fish, predators and fire risk

  • Control invasive plants that shade, smother or destabilise stream banks, using methods that prevent herbicide or physical disturbance from entering the water.
  • Assess introduced fish at affected reaches and implement approved controls where fish predation threatens eggs or tadpoles.
  • Do not introduce fish or move fish, water, rocks or equipment between catchments without approved disease and aquatic pest controls.
  • Include wildfire risk and post-fire stream and riparian recovery in the site management plan, because a translocated population was severely affected by the 2019 to 2020 fires.
  • Use fire planning that protects riparian vegetation and avoids direct damage to retained stream habitat, with prescriptions set by the relevant land manager and fire authority.

Rehabilitation actions: Monitor rehabilitation success

Breeding period: Mid spring to early summer, with calling mainly from late October to late December.

Metamorphosis period: Mid February to late March in the recovery plan.

  • Monitor vegetation establishment, bank stability, sediment, flow, water quality, rocky habitat, introduced fish, weeds and disease at rehabilitated reaches.
  • Monitor spotted tree frog presence, calling, egg deposition, tadpole development, metamorphosis and recruitment during the species’ active and breeding periods.
  • Set success measures in the approved plan using pre-disturbance habitat condition and frog records as the baseline, rather than relying only on vegetation cover.
  • Investigate and correct any decline in frog detections, egg survival, tadpole survival or recruitment, and continue monitoring for the period required by the approval.

Sources