Tasmanian Smooth Froglet (Geocrinia laevis)

Conservation status

South Australia, National Parks and Wildlife Act 1972: Rare.

Breeding season

The Tasmanian Smooth Froglet breeds in late summer and autumn. Timing may vary between sites in South Australia, Tasmania and Victoria, and egg hatching depends on winter rainfall and flooding.

Breeding mode: Females lay eggs in moist leaf litter or at the bases of grass tussocks. The eggs develop to the tadpole stage on land, then flooding allows the tadpoles to become aquatic.

Clutch size: 80 to 150 pigmented eggs.

Egg development: Eggs stick together in clumps and can remain unhatched while they await sufficient winter rainfall. Unhatched tadpoles may survive if moisture is maintained.

Incubation period: Not recorded.

Fledging or weaning: Not applicable.

Age at maturity: Not recorded.

Breeding frequency: Not recorded.

The season can shift between years and regions because successful development depends on local moisture, winter rainfall and flooding.

• Breeding and egg laying: Breeding occurs in late summer and autumn, with eggs laid in moist leaf litter or grass tussock bases.
• Terrestrial eggs and developing tadpoles: Egg clumps remain on land while they await enough moisture and winter rainfall for development to continue.
• Aquatic tadpoles after flooding: Tadpoles become aquatic after flooding, so the timing depends on when winter rain reaches the breeding site.
• Adult activity and sheltering: Adults use damp, low lying vegetated areas under leaf litter and debris, but a species specific monthly activity pattern is not established.
• Highest clearing risk: Avoid clearing moist breeding sites from late summer through winter, when eggs, developing tadpoles and recently flooded habitat may be present.

Identification: Appearance

The Tasmanian Smooth Froglet is a smooth-skinned ground frog associated with damp vegetation and debris. Field identification can be difficult, so records should include photographs, location details and call observations where possible.

Adults have smooth undersides and often show a pink patch in each armpit and groin. The underside of the hind limbs has pale pink or white mottling with dark brown markings.

The snout is rounded and the tympanum is indistinct. A reliable field size range is not established in the available species information, so do not estimate size as a primary identification feature.

Identification: Calls and similar species

Male frogs can be identified by their distinctive calls. Listen during suitable nocturnal conditions and record the call, date, time and weather.

Similar species information is limited. Do not rely on call alone where several frog species occur. Use photographs and, where needed, seek confirmation from a qualified amphibian ecologist.

• Record calling males separately from frogs seen but not heard.
• Use repeated call surveys where a site may contain suitable habitat.

Identification: Field signs and survey approach

There are no reliable species-specific signs such as droppings, nests, whitewash, stains or odour to use during a clearing inspection. Search damp ground cover, leaf litter, debris and grass tussock bases by hand and with a torch, while limiting disturbance.

In Tasmania, repeated nocturnal call surveys are a useful method for detecting frogs. Surveys of about 20 minutes over 2 to 9 nights are general guidance for most Tasmanian frog species, rather than a species-specific effort requirement for this frog.

• Record species, date, numbers, precise location and habitat description.
• Inspect potential breeding areas for frogs, eggs and tadpoles where safe and authorised.
• Use clean equipment and follow amphibian hygiene procedures between sites to reduce disease spread.

Distribution: Australian range

The Tasmanian Smooth Froglet has a south-eastern Australian distribution. Its range includes mainland areas and Tasmanian islands, with no overseas range identified.

In South Australia, it is mapped from the extreme south-east. In Victoria, it occurs in the south-west. In Tasmania, it occurs in western Tasmania and has been recorded historically in northern and central Tasmania, including King Island.

Mapped jurisdictions: South Australia, Tasmania and Victoria

Overseas range: None identified

• South Australia, extreme south-east
• Victoria, south-west
• Tasmania, including western, northern and central areas and King Island

Distribution: What the range means for projects

A site outside a known local record may still need assessment if it contains suitable damp, low-lying vegetation and seasonal wet areas. Local absence should not be assumed from a single quiet survey, particularly when conditions are dry or frogs are not calling.

• Check current state biodiversity databases and local records before finalising clearing limits.
• Treat suitable habitat as potentially occupied until an appropriately timed assessment supports another conclusion.

Habitat: Ground and vegetation features

Look for the Tasmanian Smooth Froglet in damp, low-lying vegetated areas with leaf litter, debris and grass tussocks. Habitat may be easy to overlook because breeding begins on land and water is only needed after flooding.

Potential habitat includes moist leaf litter, fallen debris and the bases of grass tussocks. Low-lying areas that retain moisture are more likely to support frogs than exposed, dry ground.

Inspect depressions, drainage lines, wet grassland margins and other places where rainfall or runoff can collect, while recognising that a permanent waterbody is not required for the egg stage.

• Damp leaf litter and accumulated plant debris
• Bases of dense grass tussocks
• Low-lying vegetated ground
• Seasonally flooded depressions and wet margins

Habitat: Site assessment

Map the extent and condition of moist ground cover before access tracks, laydown areas or vegetation removal are planned. Include connected damp patches, not only obvious open water.

Where works may alter drainage, assess whether runoff, flooding or drying patterns could change in nearby breeding habitat.

• Mark areas with suitable ground cover and seasonal inundation.
• Identify proposed work areas that would remove litter, tussocks or surface shelter.
• Plan access to avoid unnecessary vehicle movement through wet ground.

Foraging habitat: Where to look

Adult Tasmanian Smooth Froglets are carnivores that feed on invertebrates. Foraging is likely to occur close to damp ground cover where moisture supports both frogs and their prey.

Search beneath leaf litter and debris, around grass tussock bases and through low vegetation in damp areas. Frogs may be concealed during the day and more active at night or after suitable rain.

Diet: Invertebrates

Foraging pattern: Ground based, associated with damp cover

• Moist litter layers
• Dense grass bases
• Low vegetation near seasonal wet areas
• Sheltered ground beside debris

Foraging habitat: Works controls

Keep ground cover intact wherever practicable. Avoid broad scraping, unnecessary removal of debris and compaction of damp vegetated areas.

If frogs are found during works, stop the immediate activity and have a suitably experienced fauna handler assess the animal and habitat before proceeding.

• Retain leaf litter and tussock bases within exclusion areas.
• Use defined access routes rather than repeated vehicle passes.
• Keep disturbed material out of nearby wet areas.

Breeding habitat: Breeding places

Breeding occurs in late summer and autumn. Eggs are laid on land, then winter rainfall and flooding allow the tadpoles to develop in water.

Females lay 80 to 150 pigmented eggs in moist leaf litter or within the bases of grass tussocks. Eggs stick together in clumps and can remain unhatched if rainfall is delayed, provided enough moisture is present.

Breeding season: Late summer and autumn

Clutch size: 80 to 150 pigmented eggs

Development: Eggs develop on land, then flooding allows tadpole development in water

• Moist leaf litter
• Bases of grass tussocks
• Sheltered low-lying vegetation that remains damp
• Areas subject to later flooding

Breeding habitat: Protection during works

Before clearing, inspect moist litter and tussock bases as well as nearby seasonal water. A dry site at the time of inspection may still contain eggs or provide breeding habitat after rain.

Avoid clearing or disturbing potential breeding habitat during the breeding period where practicable. If this cannot be achieved, obtain project-specific advice from a qualified amphibian ecologist and the relevant regulator.

• Retain suitable breeding patches within clearly marked exclusion areas.
• Maintain natural drainage and avoid diverting runoff away from breeding habitat.
• Prevent sediment, chemicals and concrete washout from entering flood-prone areas.
• Do not move eggs or tadpoles between waterbodies.

Sheltering habitat: Shelter features

The species shelters close to the ground in damp leaf litter, debris and low vegetation. Shelter features can be small and may be removed by slashing, grading, stockpiling or vehicle movement.

Inspect beneath leaf litter and debris, around grass tussock bases and in low-lying vegetated areas. Retain natural ground cover and avoid turning over logs, rocks or debris unless this is part of an approved fauna management procedure.

• Leaf litter
• Plant debris
• Grass tussock bases
• Low, damp vegetation

Sheltering habitat: Handling and relocation

Relocation should not be undertaken casually. If a frog is exposed during works, use an appropriately trained fauna handler and follow the approved project procedure.

Any temporary holding, handling or release must minimise stress and disease risk. Do not release frogs, eggs or tadpoles into a different waterbody or unrelated site.

• Stop work around the animal until it has been assessed.
• Keep handling time as short as practicable.
• Use clean equipment and containers.
• Release only in suitable nearby habitat approved for the project.

Threats: Clearing and habitat loss

Development can affect this frog through direct removal of ground cover, changes to flooding and drainage, and disease spread. Because the species is listed as Rare in South Australia and Tasmania, avoidable impacts should be addressed early in project planning.

Slashing, grading, excavation and removal of leaf litter or tussocks can destroy shelter and land-based egg sites. Compaction can also reduce the damp ground conditions used by frogs and their prey.

• Define no-go areas around suitable damp vegetation.
• Minimise the clearing footprint and retain connected habitat.
• Avoid unnecessary removal of litter, debris and tussocks.

Threats: Drainage, flooding and pollution

Changes to surface water movement may prevent suitable breeding areas from flooding or may cause excessive drying. Sediment, chemicals, hydrocarbons and concrete washout can harm frogs and tadpoles in seasonal wet areas.

• Maintain natural drainage patterns where practicable.
• Use sediment and erosion controls before earthworks begin.
• Keep fuels, chemicals and washout areas away from wet ground and drainage lines.
• Inspect controls after rainfall and repair failures promptly.

Threats: Disease and biosecurity

Chytrid fungus threatens Tasmanian native amphibians, and the Smooth Froglet's susceptibility and host status are not resolved. Treat all sites as requiring careful amphibian hygiene.

• Clean and disinfect boots, tools, nets and containers between sites.
• Do not move frogs, eggs, tadpoles, water, mud or wet vegetation between locations.
• Report unusual sickness or mortality through the relevant state wildlife or environment authority.
• Use targeted disease sampling only under an approved monitoring or research program.

Threats: Protection and survey response

The species is profiled as an EVNT species and is listed as Rare in South Australia and Tasmania. A confirmed record or potential breeding place should trigger a review of the work method, clearing limits, timing and regulatory requirements.

South Australia: Rare under the National Parks and Wildlife Act 1972

Tasmania: Rare under the Threatened Species Protection Act 1995

• Engage a qualified amphibian ecologist before clearing suitable habitat.
• Use repeated surveys where a presence or absence decision affects the project.
• Document records in the relevant state biodiversity database.
• Obtain any required approvals before disturbing frogs, eggs, tadpoles or breeding habitat.

Survey methodology: 1. Desktop assessment

The Tasmanian Smooth Froglet is poorly known across much of its range. Use nocturnal call surveys with targeted searches of damp ground cover, leaf litter, grass tussocks and shallow inundated areas.

Map damp, low-lying and seasonally inundated areas before visiting the site.

Check records in the Natural Values Atlas and relevant state databases. Confirm whether the site is in South Australia, Tasmania or Victoria, and identify any local planning or threatened species requirements.

Review drainage, flood paths, vegetation removal, access tracks, lighting and proposed works. Give particular attention to areas with moist leaf litter or grass tussock bases.

Survey methodology: 2. Nocturnal call surveys

Survey during the most detectable period, generally spring to summer, when conditions are suitable for calling. Late summer and autumn are also relevant because this is the reported breeding period.

Use repeated nocturnal surveys. A 20 minute listening period at each survey location over 2 to 9 nights is a useful starting design where site conditions and approvals allow. Refine the effort if local detection information or a regulator requires a different design.

Survey after suitable rain or when the ground remains damp, and avoid strong wind, heavy rain and excessive background noise where possible.

Record the number and location of calling males. Use call playback only where it is approved and unlikely to disturb breeding animals.

Survey methodology: 3. Visual and disease surveys

Search damp locations under leaf litter and debris, the bases of grass tussocks, low-lying vegetation and areas that may flood after rain.

Inspect shallow flooded areas for tadpoles and frogs. Eggs may develop on land before flooding releases tadpoles into aquatic habitat.

If disease surveillance is required, use trained personnel to swab adult frogs or tadpole mouthparts for chytrid testing. Follow current decontamination and sampling protocols between sites.

Survey methodology: 4. Field records

Record the date, start and finish time, weather, recent rainfall, survey duration, observers, survey method and detection conditions.

Map each call, frog, egg mass, tadpole and potential breeding place with a precise location. Describe vegetation, leaf litter, tussock cover, moisture, inundation and nearby drainage.

Record the number of animals or calling males, photographs where suitable, and any disease signs, injury, mortality or disturbance.

Submit significant observations to the Natural Values Atlas or the relevant state biodiversity database.

Before habitat disturbance: 1. Confirm approvals and permits

Plan works to retain damp ground cover and seasonal water movement wherever possible. The species is listed as Rare in South Australia and Tasmania, so avoid relying on a general fauna protocol where the site may support breeding habitat.

Check whether the action could affect a matter protected under the EPBC Act. Seek an EPBC referral or approval where the legislation requires it.

Confirm state requirements before clearing. In Tasmania, frogs are protected and threatened species controls may apply. In South Australia, check the requirements associated with the Rare listing. In Victoria, check relevant wildlife, planning and native vegetation approvals.

If works are proposed in Queensland and may tamper with a protected breeding place, obtain advice on whether a species management program is required. The species is not mapped in Queensland in this profile, so confirm the identification and jurisdiction before applying that pathway.

Use only authorised fauna personnel for capture, handling or relocation. Do not collect animals from reserved land or private land without the required authority and permission.

Before habitat disturbance: 2. Complete a pre-clearance survey

Survey all proposed clearing areas, access routes, stockpile areas, drainage lines and temporary work areas before disturbance.

Target late summer and autumn for breeding habitat checks, and use spring to summer nocturnal call surveys when detection is generally better.

Mark moist leaf litter, grass tussock bases, low-lying vegetation, seasonal flood paths and any area where eggs or tadpoles are found. Treat these as potential breeding habitat until assessed by a suitably qualified ecologist.

Repeat the assessment if rainfall, flooding or design changes create new wet habitat.

Before habitat disturbance: 3. Apply avoidance and exclusion measures

Retain breeding and sheltering habitat in place wherever practicable. Keep leaf litter, debris, tussocks, soil moisture and natural drainage intact.

Define a site-specific no-go area around confirmed animals, eggs, tadpoles and breeding habitat. Set the boundary with the project ecologist and regulator rather than applying an unsupported generic distance.

Fence exclusion areas with a durable, clearly visible barrier. Keep vehicles, storage, spoil, lighting and sediment runoff outside the exclusion area.

Do not drain, fill, compact or burn damp low-lying habitat without an approved method and ecological sign-off.

Before habitat disturbance: 4. Induct the work crew

Explain the froglet's appearance, likely sheltering places and call to all workers before clearing starts.

Show the exclusion areas and the stop-work process. Workers must not handle frogs, eggs or tadpoles.

Include hygiene measures to reduce pathogen transfer. Clean and disinfect footwear, equipment and vehicles between frog sites, and prevent dirty water moving into retained habitat.

Provide the spotter catcher and site supervisor with contact details for the project ecologist, wildlife carer and veterinarian.

During habitat disturbance: 1. Use staged clearing

Clear in a controlled sequence from retained habitat towards already disturbed ground. Stop work whenever an animal, egg mass, tadpole group or potential breeding place is found in the work area.

Install and check exclusion fencing before machinery enters the site.

Remove movable materials by hand first, including debris that may shelter frogs. Search each item before it is moved and replace habitat features where they are retained.

Clear small sections progressively. Pause between stages so the fauna observer can inspect the next area and confirm that animals have not moved into the work zone.

Keep machinery out of wet depressions, tussock bases, leaf litter and flood paths unless the approved method specifically allows entry.

During habitat disturbance: 2. Give the spotter catcher stop-work authority

The fauna spotter catcher must be authorised for the work and empowered to stop machinery immediately.

Stop work if a Tasmanian Smooth Froglet, eggs, tadpoles, a possible breeding place or an unexpected concentration of frogs is found.

Establish a temporary exclusion area, keep people and machinery clear, and contact the project ecologist or regulator for direction before restarting.

Do not use noise, water, chemicals or handling to force animals from cover.

During habitat disturbance: 3. Handle and relocate animals lawfully

Only an authorised and appropriately trained person may capture or handle a froglet. Keep handling brief, use clean equipment and minimise skin contact and stress.

Place an animal in a secure, cool container with suitable clean moisture while advice is obtained. Do not expose it to sun or allow escape or contact with other animals.

Do not move frogs, eggs or tadpoles to another water body or unrelated site. Relocation should occur only under the approved plan and to suitable habitat as close as practicable to the capture location.

If an animal is found in a building or beside a residence, release it immediately, as close as practicable, in suitable habitat where this is lawful and safe.

During habitat disturbance: 4. Manage breeding places and injuries

Treat eggs and tadpoles as active breeding evidence. Stop the relevant work area and obtain advice before disturbing, draining or filling it.

Do not remove an active breeding place under a general clearing instruction. Follow any permit, approval, species management program or regulator direction.

For an injured frog, place it in a secure, clean container, keep it cool and quiet, and contact a licensed wildlife carer, veterinarian or the relevant government authority. Do not release an injured animal without advice.

Record the location, condition, action taken, handler, destination and authority for every animal, egg mass or tadpole group managed.

After habitat disturbance: 1. Complete post-clearance checks

Post-clearance checks help find animals missed during staged clearing and identify damage to retained breeding habitat. Keep the project ecologist involved until exclusion areas and restoration measures are stable.

Inspect cleared ground, remaining debris, exclusion fencing, drainage paths and retained habitat after each clearing stage.

Search under disturbed cover and around wet depressions for live or injured frogs, eggs and tadpoles. Check for sediment, drying, compaction, chemical spills and altered water flow.

Undertake follow-up nocturnal call surveys where habitat remains suitable, particularly during spring to summer or after suitable rain.

After habitat disturbance: 2. Monitor retained habitat

Set repeat survey points in retained and rehabilitated habitat. Use the same locations, methods, timing and effort so results can be compared.

Record calling males, frogs, eggs, tadpoles, habitat condition, water presence, weed cover, lighting and evidence of disease.

Use mark-recapture only where a more accurate abundance estimate is required and the method has been approved. Do not mark or handle animals without suitable authority.

After habitat disturbance: 3. Close out incidents and reporting

Report breaches of exclusion areas, unapproved handling, injury, mortality, disease concerns, sediment release and damage to breeding habitat to the site supervisor and project ecologist immediately.

Notify the relevant regulator or permit authority where required by an approval or permit. Keep records of notifications and corrective actions.

Provide final records to the land manager, including survey effort, detections, animals handled, breeding places affected, habitat retained and rehabilitation completed.

Review each incident with the construction team and amend the induction, fencing, sequencing or supervision arrangements before work continues.

After habitat disturbance: 4. Manage relocated animals

Check relocated animals only as required by the approved method and without unnecessary handling.

Confirm that the release location remains damp, connected to suitable cover and free from active construction impacts.

Do not release captive-held or displaced frogs into a new water body or outside the approved release location. Escalate any uncertainty to the fauna ecologist or regulator.

Rehabilitation actions: 1. Restore ground habitat

Rehabilitation should recreate the wet, sheltered ground conditions used by the Tasmanian Smooth Froglet. Focus on natural habitat structure and hydrology rather than artificial structures that do not suit this ground-breeding frog.

Replace or retain moist leaf litter, natural debris and grass tussocks in suitable low-lying areas.

Re-establish local native groundcover and tussock vegetation using locally appropriate provenance where practicable.

Repair compaction and restore natural drainage and seasonal flooding patterns. Prevent sediment, concrete washout, herbicide and other pollutants from entering wet habitat.

Do not remove logs, rocks, litter layers or other shelter features from rehabilitation areas unless they create a demonstrated safety or ecological risk.

Rehabilitation actions: 2. Avoid unsuitable artificial structures

Do not install nest boxes, bat boxes, artificial roosts or elevated nest structures for this species. The Tasmanian Smooth Froglet lays eggs in moist leaf litter or grass tussock bases, and its tadpoles become aquatic after flooding.

Where breeding habitat has been lost, recreate moist leaf litter, tussock bases and appropriate seasonal inundation rather than constructing a generic artificial breeding structure.

Use any constructed wet area only where its hydrology, water quality, disease risk and connection to suitable terrestrial cover have been assessed by a frog ecologist.

Rehabilitation actions: 3. Control weeds and protect water

Control weeds by methods that do not injure frogs or contaminate wet areas. Avoid broadscale chemical application in or beside occupied habitat unless specifically approved.

Keep sediment controls in place until groundcover is established and exposed soil is stable.

Maintain clean surface water and prevent polluted or pathogen-bearing water, soil and equipment from entering retained or rehabilitated habitat.

Inspect after heavy rain and repair erosion, blocked drainage, scour and damaged exclusion fencing.

Rehabilitation actions: 4. Manage lighting and ongoing disturbance

Direct construction and security lighting away from retained wet ground, tussocks and seasonal flood paths.

Use the lowest practical light levels, shield fittings and avoid unnecessary overnight lighting beside habitat.

Restrict vehicle access, mowing, slashing, stockpiling and routine maintenance in rehabilitated areas, especially during the late summer to autumn breeding period.

Keep rehabilitation areas free of domestic animals, introduced predators and stored materials.

Rehabilitation actions: 5. Set long-term monitoring triggers

Monitor vegetation cover, leaf litter, moisture, seasonal inundation, weeds, sediment and frog detections at agreed intervals.

Use repeated nocturnal call surveys, visual searches and tadpole checks where suitable habitat remains. Compare results with pre-clearance records.

Set corrective triggers for drying, weed dominance, loss of tussock cover, altered flooding, disease signs, repeated mortality or decline in frog detections.

Continue monitoring until the ecologist and land manager agree that habitat structure, hydrology and maintenance responsibilities are stable.

Sources

• Tasmanian Frogs, Tasmanian Government: https://nre.tas.gov.au/wildlife-management/fauna-of-tasmania/reptiles-and-frogs/tasmanian-frogs
• Smooth Frog, grasslands.ecolinc.vic.edu.au: https://grasslands.ecolinc.vic.edu.au/fieldguide/fauna/smooth-frog
• Depar tment of, Tasmanian Government: https://nre.tas.gov.au/Documents/Tasmanian-Frog-Management-Plan.pdf
• Keeping Tasmanian Reptiles & Amphibians in Tasmania, Tasmanian Government: https://nre.tas.gov.au/documents/keeping-tasmanian-reptiles-brochure.pdf
• Occurrence records for the distribution map, Atlas of Living Australia: https://biocache.ala.org.au/