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Western Swamp Turtle (Pseudemydura umbrina)

The Western Swamp Turtle is a small, short-necked, wholly carnivorous freshwater tortoise endemic to the Swan Coastal Plain of Western Australia. It depends on shallow, seasonal wetlands and nearby summer aestivation refuges, so clearing, drainage, altered hydroperiods, fencing, fire and predator access can affect it directly on development sites.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Western Australia, Biodiversity Conservation Act 2016: Critically endangered.

Breeding season

Western Swamp Tortoises mate in water from late autumn through winter, carry eggs through spring and nest in late spring to early summer. Clearing risk is highest from nesting through autumn, when nests, eggs, hatchlings and aestivating tortoises may be on or under the ground.

Reproductive mode: Egg-laying. Females construct underground nests with their forelegs.

Clutch size: Usually three to five eggs. One clutch is produced each year in the wild.

Incubation: Approximately 180 days, with hatching triggered by lower temperatures and winter rain.

Size at hatching: Hatchlings weigh less than 50 g. They need to reach about 25 g during their first six months to survive the following summer.

Age at maturity: Females generally mature at about 112 mm carapace length and around 10 to 15 years of age. Reported wild ages range from about 6.5 to 20 years, depending on habitat conditions.

Nest or egg sites: Underground nest chambers on suitable ground near seasonal wetlands. The documents do not provide a more specific nest substrate.

Breeding frequency: One clutch per year in the wild. Captive females may occasionally produce a second clutch of two eggs.

Confirm timing at each site before works, because rainfall controls wetland filling, mating, egg production and hatchling emergence, while temperature controls activity, drying and hatching.

  • Mating: Mating starts in autumn after ephemeral swamps fill and continues through winter, when wetlands are at their highest. In the breeding programme, pairing generally runs from early July to the first week of September, while wild mating is described as occurring through winter and spring activity periods.
  • Gravid females: Females develop preovulatory follicles in September, become gravid from about the second half of September and carry shelled eggs through October until laying in November or early December. The oviducal period is about 30 to 40 days.
  • Nesting: Females leave the water to dig underground nests and usually lay three to five eggs in November or early December. Some sources record laying from October to November, with occasional laying into early December.
  • Incubation: Eggs remain in underground nests for about 180 days after laying. Eggs laid in November or early December generally remain in the nest through summer and hatch from late April to June, with hatching linked to cooler conditions and early winter rain.
  • Hatchlings: Hatchlings emerge from late April to June, usually after early winter rains. They are less than 50 g at emergence and must grow rapidly while wetlands retain water before the next summer aestivation.
  • Active period: Adults are surface active in seasonal wetlands after they fill, usually from June or July through spring. Activity is greatest while wetlands are full in winter and while food is plentiful in spring, then declines as water temperatures rise above 28 degrees Celsius and wetlands dry, usually in November.
  • Winter inactivity: This species aestivates rather than brumates. Most individuals use underground burrows from December to March or April, emerge in April or May, and then shelter under leaf litter, fallen branches or dense low bushes; timing can extend from November to June when rainfall is late or low.
  • Highest clearing risk: Risk is highest in November and December because females are nesting, eggs are being laid and tortoises are entering aestivation. Risk remains elevated from January to June because eggs may still be in nests, hatchlings emerge from late April to June, and adults occupy underground or surface refuges that machinery can collapse or cover.

Identification

This is a small freshwater tortoise with a short neck and a compact shell. It is highly distinctive within its remaining range, but handling, trapping or translocation must be undertaken by appropriately authorised personnel.

The Western Swamp Turtle is the smallest Australian chelid. It has a short neck and a compact carapace. The only other freshwater tortoise in south-western Western Australia, the Oblong Tortoise, Chelodina oblonga, has a neck equal to or longer than the shell length.

Adult male: Up to 155 mm carapace length and 550 g.

Adult female: Up to 135 mm carapace length and 410 g.

Hatchling: 24 to 29 mm carapace length and 3.2 to 6.6 g.

Identification: Sex and behaviour

Sexes can be distinguished in adults by the shape of the plastron and the length of the tail. The species feeds and breeds in water, then leaves the wetland to aestivate during the hot, dry part of the year. It may be encountered moving overland between wetlands and aestivation refuges as water levels fall.

  • Treat any short-necked tortoise found in a seasonal wetland, nearby clay hollow, log refuge or low ground cover as a possible Western Swamp Turtle until identified by a qualified person.
  • Do not assume that a dry wetland is unoccupied. Tortoises may be aestivating outside the water during summer and autumn.

Identification: Field signs and survey detection

The species has no distinctive call, scat or slough reported in the supplied documents. Eggs are laid in a nest chamber, but the nest is not generally an obvious surface feature. Unlike other tortoises and turtles, the female digs the nest chamber with her forelegs.

  • For authorised surveys, the accepted detection method is a line of mesh drift fencing with collapsible turtle traps when free water is present, or pitfall traps beside the drift fence when areas dry.
  • Collapsible traps should remain in water and be attached flush to the drift fence. The survey method is designed to prevent desiccation, direct solar exposure and drowning during rapid water-level changes.
  • Use an experienced reptile ecologist for survey design, animal welfare, identification and any handling.

Distribution

The species is endemic to a narrow part of south-western Western Australia. Its known distribution is concentrated on the Swan Coastal Plain, north-east of Perth, with historical records extending through a narrow strip from Perth Airport towards Bullsbrook.

All confirmed records are from Western Australia. The known range lies in the Swan Coastal Plain IBRA region, in a strip about 3 to 5 km wide running roughly parallel with the Darling Scarp, from Perth Airport at Guildford to near Pearce Royal Australian Air Force Base at Bullsbrook. The estimated extent of occurrence was 100 to 150 km² in the EPBC assessment.

  • State: Western Australia only.
  • Bioregion: Swan Coastal Plain IBRA region.
  • Known range: from Perth Airport and Guildford north to near Bullsbrook, with the principal current sites north-east of Perth.

Distribution: Strongholds and subpopulations

Ellen Brook Nature Reserve contains the only naturally occurring, viable population identified in the EPBC assessment. Twin Swamps Nature Reserve has been supplemented with captive-bred animals after the natural population declined severely. Mogumber Nature Reserve was established as a translocation population, and later recovery planning also included Moore River Nature Reserve as a translocation site.

  • Ellen Brook Nature Reserve: naturally occurring mature individuals and the main natural stronghold identified in the assessment.
  • Twin Swamps Nature Reserve: a supplemented population following the collapse of the former population.
  • Mogumber Nature Reserve and Moore River Nature Reserve: translocation sites managed as part of recovery actions.

Distribution: Population size and trend

The EPBC assessment recorded a decline from about 250 individuals at Twin Swamps in the early 1960s to fewer than 10 by 1984. At the time of that assessment, Ellen Brook held an estimated 30 animals, including 10 to 15 mature individuals, while Twin Swamps held six mature individuals. The recovery plan notes that population estimates vary with survey method and are likely to be underestimates.

Historical population estimate: About 250 individuals at Twin Swamps in the early 1960s.

EPBC assessment mature individuals: About 15 to 25 mature individuals in the wild at the time of assessment.

Ellen Brook at assessment: About 30 animals in total, including an estimated 10 to 15 mature individuals.

Trend: Very severe decline since the 1960s, with ongoing concern about recruitment and climate-driven wetland drying.

Habitat

Western Swamp Turtles require a combination of shallow seasonal wetland habitat and suitable dry refuges nearby. Both parts of this habitat unit can be affected by clearing, earthworks, drainage and changes to surface water or groundwater.

The species inhabits shallow, ephemeral wetlands that fill during winter and spring. Wetlands occur on clay or sand over clay soils and may include natural clay hollows. It does not normally occur in the permanent swamps or lakes of the Swan Coastal Plain.

  • Retain seasonal wetlands, shallow depressions and clay soils within and adjacent to the development footprint.
  • Assess nearby dry refuges as part of the same habitat unit, even where no standing water is present at the time of inspection.
  • Maintain wetland water quality, inflows and hydroperiod rather than relying only on wetland boundaries shown on maps.

Habitat: Vegetation and structure

In many swamps, Melaleuca lateritia forms a canopy about 1 to 2 m above open tall sedges such as Leptocarpus canus. Fallen branches, leaf litter, low dense bushes, tree bases and natural holes in clay can provide important dry-season structure.

Typical canopy height: About 1 to 2 m above the water.

Typical wetland vegetation: Melaleuca lateritia over open tall sedges, including Leptocarpus canus.

  • Avoid removing fallen timber, dense low vegetation, leaf litter and natural clay hollows near seasonal wetlands unless their ecological function has been assessed.
  • Check the wetland margin and adjoining terrestrial areas for refuges before clearing or grading.

Habitat: Climate and elevation

The known habitat is in the Mediterranean-climate region around Perth and the northern Swan Coastal Plain, with cool, wet winters and hot, dry summers. The supplied documents do not provide an elevation range. They identify hydroperiod, soil and refuge availability as the main habitat limits.

Foraging habitat: Diet and feeding sites

Foraging occurs in standing water during the winter and spring activity period. The species is wholly carnivorous and depends on adequate wetland duration for both feeding and growth.

Western Swamp Turtles eat living aquatic prey, including insect larvae, small crustaceans and small tadpoles. They feed in shallow seasonal wetlands after water temperatures rise above about 14°C. Food intake increases as swamps warm in spring and aquatic prey become more abundant.

Food: Insect larvae, small crustaceans and small tadpoles.

Thermal activity threshold: Feeding begins when water temperatures are above about 14°C.

Active thermal range: About 14 to 30°C, with performance reported as optimal between 22 and 28°C.

  • Protect shallow water, wetland edges and aquatic vegetation that support invertebrates and tadpoles.
  • Avoid works that shorten the period of standing water during winter and spring.
  • Manage sediment, contaminants and runoff so that aquatic prey communities are not degraded.

Foraging habitat: Foraging range and timing

Tortoises use suitable habitat throughout the nature reserves and are not territorial. The supplied documents do not provide a standard foraging distance or home-range size. They leave the water when wetlands are nearly dry and water temperatures rise above about 28°C, usually in November.

  • Survey and assess all connected seasonal wetlands and adjoining movement areas rather than treating each wetland as an isolated foraging patch.
  • Do not infer absence from a dry wetland during summer or autumn.

Breeding habitat: Breeding biology

Breeding is tied to seasonal wetlands with enough water and prey for females to build energy reserves. Recruitment can fail when wetlands dry early, particularly across successive low-rainfall years.

Breeding and egg laying occur in the wetland period, with eggs laid in November or early December. Hatchlings emerge during the following autumn or winter, during or after heavy rain. Females dig nest chambers with their forelegs, which is unusual among tortoises and turtles.

Breeding and laying season: Eggs are laid in November or early December.

Clutch size: A maximum of one clutch per year, usually three to five eggs.

Hatching and emergence: Hatchlings emerge the following autumn or winter, during or after heavy rain.

Age at maturity: Usually 10 to 15 years or older.

Generation time: Estimated at about 40 to 60 years in the EPBC assessment.

Lifespan: Known to exceed 50 years; maximum lifespan is not known.

Breeding habitat: Breeding habitat features

The species breeds only in water but nests on nearby suitable ground. Successful recruitment requires a wetland to retain water long enough for females to feed and for hatchlings to grow before their first summer aestivation. Hatchlings need to reach about 25 g in their first six months to survive that period.

Hatchling first-summer threshold: About 25 g body weight is needed in the first six months for reliable survival through the first summer dormancy.

Rainfall requirement for recruitment: Two successive years of average or above-average rainfall are needed for effective recruitment.

  • Retain shallow wetland water, aquatic prey and nearby nest and refuge habitat through the breeding season.
  • Avoid draining, filling, compacting or isolating clay wetland margins before and during the egg-laying period.
  • Allow for the fact that two successive years of average or above-average rainfall may be needed for effective recruitment.

Sheltering habitat

Sheltering habitat is used mainly during summer and autumn aestivation, but also during the transition from aquatic activity to dormancy. Refuges may be underground or on the surface, depending on site conditions and individual behaviour.

At Ellen Brook, tortoises use naturally occurring holes in gilgai clay. At Twin Swamps, refuges have included rabbit burrows, holes at tree bases, holes left by rotting roots, leaf litter, fallen branches and dense low bushes. At Mogumber, released tortoises have used leaf litter and fallen timber, as well as artificial aestivation tunnels.

  • Inspect and protect clay hollows, animal burrows, tree bases, fallen logs, fallen branches, leaf litter and dense low bushes near seasonal wetlands.
  • Do not fill, collapse or block potential aestivation refuges during earthworks or access-track construction.
  • Where fencing is required, prevent tortoises from being trapped away from water or directed towards farm dams and other hazardous water sources.

Sheltering habitat: Seasonal refuge use

At Twin Swamps, radio tracking found that most tortoises spent the hottest summer months, usually December to March or April, underground in rabbit burrows. They emerged in April or May and used leaf litter, fallen branches or dense low bushes during late autumn before returning to wetland activity.

Main summer aestivation: Usually December to March or April at Twin Swamps.

Autumn transition: Tortoises may emerge from underground refuges in April or May and use surface cover before the next wet period.

  • Treat dry-season refuge areas as occupied habitat from late spring through autumn, not as unused ground.
  • Use refuge-sensitive clearing methods and pre-clearing searches where seasonal wetlands or known populations occur.

Sheltering habitat: Fire and refuge type

Surface refuges such as leaf litter and fallen branches are more exposed to fire than underground clay holes or burrows. Fire was identified as a particular concern at Twin Swamps, where many tortoises used surface aestivation refuges.

  • Protect underground refuges and retain unburnt refuge patches where practicable.
  • Plan fire management around known wetland and refuge areas, especially where aestivation occurs in surface litter or fallen timber.

Threats: Clearing, development and fragmentation

The main risks are loss and degradation of seasonal wetlands, shortened wetland hydroperiods, predation and the loss of refuge habitat. Because the species has very few mature individuals and breeds slowly, localised disturbance can have population-level consequences.

Most of the former habitat on the Swan Coastal Plain has been cleared, urbanised, intensively farmed or mined for clay used in brick and tile manufacture. Clearing and drainage have destroyed much of the original habitat. Small reserves and fragmented habitat also increase the chance that animals move into unsuitable or hazardous areas.

  • Avoid clearing seasonal wetlands, clay hollows and adjoining aestivation habitat.
  • Include wetland buffers, movement areas and dry refuges in impact assessment and construction controls.
  • Control access by plant and vehicles across wetland margins and refuge areas.

Threats: Hydrology and climate drying

Reduced winter rainfall, groundwater decline, groundwater abstraction and hotter summers can shorten the wetland hydroperiod. Short hydroperiods reduce feeding time, limit female egg production and prevent hatchlings from reaching the body mass needed to survive their first summer. Existing translocation sites have also experienced shortening hydroperiods.

Recent hydroperiod concern: Historical wetlands held water for about 5 to 7 months, while recent low-rainfall years have shortened hydroperiods to about 3 to 4 months.

Potential southern-site comparison: In a 2016 trial, two southern wetlands held water 6 to 8 weeks longer than the Moore River comparison site.

  • Assess changes to surface-water inflows, groundwater, drainage and wetland drying before construction.
  • Prevent artificial drainage and avoid pumping or dewatering that reduces wetland persistence.
  • Monitor wetland water levels and hydroperiod during works and for the required post-construction period.

Threats: Predators and fencing

European Red Foxes can kill adults and juveniles and may destroy eggs. Kookaburras may take eggs and hatchlings, while Australian Ravens and introduced rats are believed to attack juveniles. Fox-proof fencing has reduced predation at reserves, but fence breaches remain possible and poorly designed fencing can prevent tortoises reaching water or cause them to die from overheating.

  • Maintain predator exclusion fencing and inspect it regularly for breaches.
  • Use tortoise gates or equivalent escape points where fencing could intercept movements between wetlands and adjoining land.
  • Control or manage foxes, rats and other predators under the approved recovery and site management programme.

Threats: Fire, roads and construction activity

Fire can destroy surface aestivation refuges and may have contributed to the decline at Twin Swamps. The supplied documents do not quantify road mortality, but tortoises move overland between water and aestivation sites, so roads, tracks, drains and fencing can obstruct or expose movements.

  • Keep construction traffic and temporary access routes away from wetland margins and known refuge areas.
  • Use fauna-sensitive traffic controls where overland movement is possible, particularly as wetlands dry in late spring.
  • Manage hot works, firebreaks and planned burns to avoid occupied surface refuges.

Threats: Disease and handling

A skin disease has been reported in the species, although the supplied documents do not provide enough information to describe its current distribution or project risk. Captures, translocations and captive breeding require disease-aware hygiene and animal welfare procedures.

  • Use clean equipment between wetlands and follow project or recovery-team hygiene procedures.
  • Do not move a tortoise between wetlands unless the movement is authorised and forms part of an approved conservation programme.
  • Record injuries, abnormal skin condition and mortality and refer observations to the relevant wildlife authority or recovery team.

Survey methodology: 1. Habitat and records assessment

Survey design must reflect the Western Swamp Tortoise’s highly restricted distribution and specialised habitat. Before fieldwork, confirm whether the project is within or near recorded habitat on the Swan Coastal Plain, including seasonal wetlands on clay or sand over clay soils with nearby aestivation refuges.

Map shallow, ephemeral winter and spring wet swamps, clay or sand over clay soils, nearby holes, burrows, leaf litter, fallen branches and tree bases that may provide summer aestivation refuges.

Check current and historical records, recovery plans, state records and the Australian Government protected matters databases before selecting survey sites.

Treat suitable habitat as potentially occupied where records are absent, because the species is difficult to detect and occurs in very small populations.

Survey methodology: 2. Aquatic trapping

Use mesh drift fences with collapsible turtle traps when standing water is present, as this is the only acceptable and successful trapping method specified for the species in the survey guidelines.

Use black plastic mesh of about 10 millimetres and attach collapsible traps directly to the drift fence with a metal stake threaded through the netting and fence mesh.

Set traps flush with the substrate, with the trap throat covered by water where possible, and lower the bars when necessary for shallow water.

Check traps frequently enough to prevent desiccation, solar exposure, predation or drowning, and provide escape structures for any mammals caught in or beside the fence.

Conduct aquatic trapping after swamps fill, usually from June or July, through the winter and spring activity period. Tortoises are generally active in the water from about 2.00 pm to 5.00 pm.

Trap design: Mesh drift fences with collapsible turtle traps

Mesh size: About 10 millimetres

Typical activity period: June or July to November, with afternoon activity generally from 2.00 pm to 5.00 pm

Survey methodology: 3. Dry-swamp pitfall trapping

If a trap line dries out, dig pitfall traps beside the drift fence, following the species-specific survey guideline.

Add small branches or other suitable escape structures for trapped mammals and inspect traps frequently.

Do not use unapproved trapping methods for this species, particularly methods that expose tortoises to direct sun, desiccation or predation.

Survey methodology: 4. Seasonal detection and survey conditions

Plan surveys while swamps contain water and tortoises are feeding, because the species feeds and breeds only in water.

Include the period when swamps are nearly dry and tortoises move to aestivation refuges, usually around November, if the project may disturb nearby leaf litter, fallen branches, burrows, holes or tree bases.

Record rainfall, water depth, hydroperiod, water temperature, vegetation, soil type, refuge features and predator controls during each survey.

Recognise that short hydroperiods reduce activity and recruitment, so a negative result from a dry or rapidly drying swamp does not demonstrate absence.

Water temperature associated with departure to aestivation: Above 28 degrees Celsius

Egg laying: November or early December

Hatchling emergence: The following autumn or winter, during or after heavy rain

Survey limitation: The documents do not prescribe a fixed number of trap nights, transect length or survey area; set effort with a qualified herpetologist and the relevant regulator

Survey methodology: Minimum effort and reporting

  • Use a qualified herpetologist familiar with Western Swamp Tortoise trapping and handling for any targeted survey.
  • Obtain approval for the survey method, trapping equipment and animal handling before fieldwork starts.
  • Survey all suitable seasonal wetlands and adjoining aestivation refuge habitat that may be affected directly or indirectly by the project.
  • Repeat surveys across appropriate wet and dry seasonal conditions where one survey cannot address detectability or hydroperiod effects.
  • Record the date, time, weather, rainfall, water presence, trap locations, trap effort, captures, measurements, photographs, microchip or other identification details, habitat condition and release location.
  • Submit confirmed records, including reliable negative survey information where requested, to the relevant Western Australian wildlife database and the Australian Government records system.
  • Report any new occurrence immediately to the project environmental officer and the relevant state wildlife authority.

Before habitat disturbance: Avoid and minimise

Avoiding disturbance is the preferred control because the species has a very small range, low fecundity, slow growth and few mature individuals. Treat seasonal wetlands and nearby aestivation refuges as connected habitat units, not as isolated work areas.

  • Avoid clearing or filling shallow, ephemeral winter and spring wetlands on clay or sand over clay soils.
  • Retain nearby natural holes in clay, tree-base holes, animal burrows, leaf litter, fallen branches, logs and low dense vegetation used for summer aestivation.
  • Retain wetland water regimes and avoid drainage, groundwater interception, excessive pumping, contamination and activities that shorten the hydroperiod.
  • Avoid barriers between wetlands and retained aestivation refuges, and retain movement routes between occupied or suitable habitat patches.
  • Keep all work areas, access tracks, stockpiles, sediment controls and laydown areas outside wetlands and adjoining refuge habitat wherever practicable.
  • Do not assume that a fenced reserve or a translocation site is unoccupied, because Twin Swamps, Mogumber and other sites have been supplemented with captive-bred animals.

Before habitat disturbance: Approvals and work planning

  • Check the EPBC Act before work starts because the species is listed as Critically Endangered nationally.
  • Obtain any Western Australian approvals, permits and wildlife authorisations required for clearing, trapping, handling, translocation, release, rehabilitation or disturbance of threatened fauna.
  • Refer the action under the EPBC Act where the project may have a significant impact on the species or its habitat.
  • Prepare a species-specific fauna management plan that identifies wetlands, aestivation refuges, exclusion zones, survey timing, machinery controls, stop-work triggers, handling authority and reporting responsibilities.
  • Schedule ground disturbance outside the period when tortoises are active in water, where practicable, and avoid work during wetland filling, winter and spring feeding, breeding in November and early December, and hatchling emergence after heavy rain.
  • Stage works so that habitat is retained until surveys, approvals, fauna controls and any authorised relocation arrangements are complete.

Before habitat disturbance: Site preparation

  • Complete a pre-clearance survey during suitable wetland conditions and inspect adjoining terrestrial habitat for aestivation refuges before machinery enters the site.
  • Mark wetland boundaries, holes, burrows, leaf litter, fallen branches, logs, tree bases and other retained habitat features on plans and on the ground.
  • Install exclusion fencing around retained wetlands and refuge habitat where fencing will not block tortoise movement or create a hazard.
  • Use tortoise gates or equivalent approved passage arrangements where temporary fencing could otherwise trap animals or direct them towards farm dams, roads or other hazards.
  • Brief all operators, spotter catchers and supervisors on the species’ appearance, habitat, seasonal movements, stop-work procedure and reporting chain.

During habitat disturbance: Daily controls

A fauna spotter catcher must work as part of the construction team, with authority to pause machinery and access to the project environmental officer. The small size of the species and its use of wetland and terrestrial refuges make slow, staged clearance necessary.

  • Inspect exclusion fencing, tortoise gates, wetland edges, refuge features, access tracks and machinery exclusion zones before work each day.
  • Check weather, recent rainfall, water levels and hydroperiod conditions before starting earthworks near suitable habitat.
  • Use a spotter catcher during vegetation removal, earthworks, drainage works, dewatering, trenching and movement of logs, branches, rocks, soil or other refuge material.
  • Keep machinery out of retained wetlands and refuge habitat, and use clearly marked exclusion zones rather than relying on operator judgement.
  • Stop work if fencing fails, water enters an excavation, a tortoise is found, a refuge feature is damaged unexpectedly, or the spotter catcher cannot maintain safe visual control of the work area.
  • Record daily inspections, work areas, machinery used, cleared area, weather, captures, incidents, controls and any departures from the fauna management plan.

During habitat disturbance: Spotter catcher and machinery procedure

  • Brief the operator before each work area is entered and agree the stop signal and restart authority.
  • Clear vegetation and soil in short, sequential sections so the spotter catcher can inspect the exposed ground, wetland margin and refuge features before the next section begins.
  • Move logs, branches, rocks, leaf litter and other potential refuges by hand or with machinery under direction, stopping immediately if a tortoise or burrow is encountered.
  • Do not allow machinery to crush, drag or bury a tortoise, and do not use machinery to remove an occupied refuge feature.
  • Keep an exclusion area around any detected tortoise until the authorised handling or protection decision is made.

During habitat disturbance: Animal found or injured

  • Stop work immediately and notify the fauna spotter catcher, project environmental officer and relevant wildlife authority when a Western Swamp Tortoise is found.
  • Do not handle the animal unless the person is authorised under the project approval and relevant wildlife legislation.
  • Do not move an animal offsite or establish a new population without approval from the recovery team and relevant authorities, because translocation is a formal conservation action.
  • Where movement is authorised, place the tortoise in a secure, shaded, temperature-appropriate container and release it only into approved nearby retained habitat with suitable water or aestivation refuge conditions.
  • Keep handling, restraint, transport and holding time as short as practicable, and do not place the tortoise in direct sun, dry conditions, unsafe water or an unapproved enclosure.
  • Take an injured tortoise to an approved wildlife veterinarian or wildlife carer arranged through the relevant authority, and record the condition, photographs, location, treatment and outcome.
  • Do not release a recovered animal at a different site unless the release has been approved.

During habitat disturbance: Stop-work records and escalation

  • Treat a confirmed Western Swamp Tortoise, an unidentified chelid that cannot be excluded, or evidence of occupation such as a fresh capture or reliable sighting as a stop-work trigger in the affected work area.
  • Keep work stopped until the spotter catcher and project environmental officer have inspected the area and implemented the approved response.
  • Report any death, injury, unauthorised handling, failed exclusion control, hydrological impact or habitat damage to the relevant regulator as required by the approval.
  • Photograph the animal and habitat where this can be done without disturbance, record coordinates, date, time, weather, water condition, activity and observers, and submit the record to the relevant state wildlife database.

After habitat disturbance: Post-clearance checks

Post-clearance work must confirm that no tortoises remain in disturbed habitat and that retained wetlands and aestivation refuges continue to function. Monitoring should focus on water persistence, recruitment and the condition of connected refuge habitat.

  • Inspect the cleared area, wetland margins, excavations, stockpile areas, temporary fencing and retained refuge habitat after each work stage.
  • Complete additional checks after rainfall, wetland drying, dewatering, flooding or removal of temporary barriers.
  • Remove temporary hazards, restore tortoise gates and confirm that animals cannot become trapped against fences, in pits, in drains or in farm dams.
  • Confirm that no logs, branches, leaf litter, holes, burrows or tree-base refuges were removed or buried outside the approved footprint.

After habitat disturbance: Monitoring and reporting

  • Monitor retained wetlands for water presence, hydroperiod, water quality, vegetation condition and evidence of tortoise use during the recovery period specified in the approval.
  • Monitor nearby aestivation refuges for disturbance, fire damage, weed invasion, erosion and loss of cover.
  • Use the approved trapping and monitoring methods if population monitoring is required, rather than casual searches alone.
  • Report monitoring results, captures, injuries, deaths, habitat loss, control failures and corrective actions to the project environmental officer and relevant authorities.
  • Update the relevant Western Australian wildlife database and Australian Government records with verified observations and mortality records.

After habitat disturbance: Corrective actions and offsets

  • Repair fencing, drainage controls, wetland edges, refuge features and revegetation failures as soon as they are identified.
  • Review the fauna management plan if the wetland dries earlier than expected, recruitment is not detected, animals leave the retained area, or project impacts extend beyond the approved footprint.
  • Implement any approved offset, habitat acquisition, reserve extension, rehabilitation or recovery-plan contribution required for residual impacts.
  • Do not treat captive breeding or translocation as a substitute for avoiding loss of occupied or suitable habitat.

Rehabilitation actions: Wetland and refuge restoration

Rehabilitation should restore the seasonal wetland, its food resources and nearby summer refuges. Design must suit a carnivorous tortoise that feeds and breeds in water, then leaves the wetland to aestivate when water levels and temperatures change.

  • Reinstate shallow winter and spring wetland depressions on clay or sand over clay soils where hydrology can be restored without damaging other conservation values.
  • Design drainage and water controls to retain water through the winter and spring feeding period and avoid rapid drying caused by altered runoff or groundwater conditions.
  • Retain or reinstate natural holes in clay, tree-base holes, animal burrows, leaf litter, fallen branches, logs and dense low vegetation near the wetland.
  • Use artificial aestivation tunnels only where they are approved by the recovery team and designed to provide safe summer refuge without trapping tortoises.
  • Maintain open shallow water and wetland vegetation that supports aquatic invertebrates, small crustaceans, insect larvae and small tadpoles, which form the species’ food.
  • Do not create permanent deep water as a default, because the species is associated with shallow ephemeral wetlands and does not occur in the permanent swamps of the Swan Coastal Plain.

Rehabilitation actions: Planting and habitat structure

  • Re-establish local wetland vegetation, including Melaleuca lateritia shrubs where appropriate, with an open tall sedge layer such as Leptocarpus canus.
  • Retain a low, open structure over the wetland rather than allowing dense shading to eliminate shallow warm water and feeding areas.
  • Place locally sourced fallen branches and logs near, but not across, wetland access routes and approved monitoring lines to provide aestivation cover.
  • Use nest boxes only where an approved design and monitoring plan demonstrate a need, because the species nests in soil and its known refuges are primarily natural holes, burrows, leaf litter, branches and tree bases.

Rehabilitation actions: Threat and reserve management

  • Control foxes, rats and other predators in accordance with the approved recovery or reserve management programme.
  • Manage ravens and kookaburras, where approved and justified by the management plan, because they may attack eggs, hatchlings and juveniles.
  • Use fire planning that protects surface aestivation refuges, particularly where tortoises use leaf litter and fallen branches rather than underground holes.
  • Control weeds and prevent sediment, pollutants and altered drainage from entering seasonal wetlands.
  • Maintain fencing and tortoise gates so animals are not forced into unsafe farm dams, roads or other areas where overheating, entrapment or predation can occur.

Rehabilitation actions: Rehabilitation monitoring and success

Recovery-plan objective: Create at least three wild naturally recruiting populations, increase mature individuals in the wild to more than 50, and conduct a translocation at a fourth site

Recruitment requirement: Two successive years of average or above-average rainfall are needed for effective recruitment under the documented ecology

Known critical activity period: Winter and spring feeding in water, followed by summer and autumn aestivation on land

  • Monitor wetland hydroperiod, water depth, water temperature, prey availability, refuge condition and vegetation establishment through wet and dry seasons.
  • Use approved capture or monitoring methods to assess adult, sub-adult and juvenile presence and evidence of recruitment.
  • Treat successful rehabilitation as more than plant establishment: the site should retain water during the feeding period, provide nearby aestivation refuges, support prey and remain connected to retained habitat.
  • Investigate failure where swamps dry before juveniles can grow, females do not reproduce, predators breach controls, fire removes surface refuges, or no recruitment is detected.
  • Set project-specific completion thresholds with the recovery team and regulator, using the recovery plan’s broader objectives of naturally recruiting wild populations and more than 50 mature individuals in the wild as the conservation context.

Sources