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Pygmy Bluetongue (Tiliqua adelaidensis)

The pygmy bluetongue lizard is a small, endangered skink endemic to remnant native temperate grasslands in the mid-north of South Australia. It shelters in abandoned spider burrows, so clearing, soil disturbance, compaction, altered drainage and trampling can destroy both lizards and the burrows they need on development sites.

Conservation status

Commonwealth, EPBC Act 1999: Endangered.

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

Breeding season

Pygmy Bluetongues mate in spring, give birth from January to March, and disperse from maternal burrows during late summer and early autumn. Clearing is most sensitive in October to November, February to March, and during winter brumation when animals are sheltering underground.

Reproductive mode: Viviparous, giving birth to live young.

Litter size: 1 to 4 young, with a reported mode of 3.

Gestation: Not recorded.

Size at birth: Approximately 45 mm snout to vent length and 1.5 g.

Age at maturity: Sources report males breeding from 1 year, females from approximately 3 years, and first breeding at 2.5 years during the third spring.

Birth sites: Maternal burrows, usually abandoned spider burrows of trapdoor or wolf spiders. Narrow vertical burrows are about 1 to 2 cm wide.

Breeding frequency: Up to 4 young each season. The sources do not otherwise quantify breeding frequency.

Confirm timing locally before works begin, as birth and activity dates may shift with local temperature and rainfall, and drought has been associated with lower fecundity.

  • Mating: Mating occurs in October and November. Males may leave their burrows for a day or longer while searching for females.
  • Gravid females: Females are reported as heavily gravid in January. The sources do not record the full gestation period, so later months are not mapped as gravid.
  • Births: Births occur from late January to late March, with most births recorded in February. Females may have young with them in burrows from mid-January to mid-March.
  • Newborns: Newborns occur from January to March, with February the main birth month. Young remain in the maternal burrow for 1 to 12 weeks before dispersing to smaller burrows.
  • Active period: Adults are generally surface active from September to May, basking at burrow entrances and making short forays. Activity and capture rates peak in November and December, while males are more mobile during spring.
  • Winter inactivity: Brumation is reported from June to August. Animals remain in burrows and may be unable to escape clearing machinery or ground disturbance.
  • Highest clearing risk: Risk is highest in February and March, when young are born and disperse, and in October and November, when males move between burrows to mate. Winter clearing from June to August can also kill animals sheltering in burrows, and disturbance to burrows should be avoided year round.

Identification

This is a small, secretive, short-legged skink that is usually detected in a spider burrow rather than moving across open ground. It often retreats immediately when approached, so handling and survey work must avoid damaging the burrow.

The pygmy bluetongue has a heavy, elongate body, short limbs, a large head and a relatively short tail. Dorsal colour ranges from grey-brown to orange-brown or medium tan, sometimes with irregular black flecks or spots on the back and flanks. The underside is cream. Unlike other Australian Tiliqua species, its tongue is pink, not blue.

  • Adults commonly have a snout to vent length of about 90 to 110 mm and a total length of less than or about 20 cm.
  • The body scales are small and smooth. The larger head scales are thickened and can give the head an armoured appearance.
  • The species is strongly diurnal and may be seen with its head, hind legs or tail tip at the burrow entrance, basking or waiting to ambush prey.

Identification: Size and sex differences

Adult males are generally shorter-bodied than females and have relatively wider heads. Females can reach a snout to vent length of about 110 mm, while the maximum recorded male snout to vent length is about 104 mm.

  • Newborn young are about 45 mm snout to vent length and weigh about 1.5 g.
  • At about one year of age, juveniles are approximately 75 to 85 mm snout to vent length and weigh about 6 to 10 g.
  • Males can reproduce in the spring of their second year. Females may reproduce at that age, but some require another year.

Identification: Similar species and field signs

The combination of very small size, short limbs, large head, pink tongue and use of spider burrows makes this species distinctive in its range. Other Tiliqua species are much larger and generally do not use spider burrows in this way.

  • Cyclodomorphus branchialis and C. venustus can be similar in size and greyish colouring, but they have longer tails, usually about as long as the body, and vertical black barring or spots on the sides of the neck. Their tails can be shed and regrown, whereas the pygmy bluetongue tail cannot be shed.
  • Look for small, circular spider burrow entrances about 20 to 25 mm wide, often with slight bevelled wear at the edge. The burrow may be angled, partly concealed by vegetation and located close to a tussock.
  • There are no reliable species-specific tracks, calls, nests, sloughs or eyeshine records provided in the source documents. Scats may contain insect remains and plant material, but are not described as a dependable field identification sign.
  • Do not excavate burrows during routine survey. Use a fibre-optic endoscope of 8 mm diameter or less where authorised, and record a close-up photograph for verification of any new locality.

Distribution

The species is endemic to South Australia. Its remaining distribution is concentrated in the mid-north, where small subpopulations are separated by cropped land, roads and other unsuitable areas.

The current range extends from Peterborough in the north to Bagot Well and Kapunda in the south, and west to the South Hummocks north of Port Wakefield. Historical records extended south to the Adelaide area, including Marion, and north to Mannanarie. The species appears to have been lost from the southern part of its former range.

  • Known sites occur in the mid-north of South Australia, including the northern Mount Lofty Ranges and hinterland, the Burra area, Peterborough, Jamestown, Auburn, Blyth, Kapunda, Bagot Well, Kulpara and the South Hummocks.
  • Most sites are on private agricultural properties that have been used for sheep grazing. Many are small and surrounded by cropped or otherwise unsuitable land.
  • The species is associated with remnants of native temperate grassland, including the Iron-grass Natural Temperate Grassland of South Australia, which is itself nationally listed as critically endangered.

Distribution: Subpopulations and trends

The species occurs in scattered, largely disconnected subpopulations. Limited dispersal means that most sites are treated as separate subpopulations, although some apparently isolated sites may form larger metapopulations.

Extent of occurrence: About 7,000 km²

Area of occupancy: Less than 500 km²

Population estimate: Approximately 5,000 individuals was estimated in 2000. Current size is unknown, with estimates under 10,000.

Known site count: Approximately 30 to 37 disjunct sites in recent sources

  • All known populations are considered important because the species has a restricted and fragmented distribution.
  • The species has been recorded from approximately 30 to 37 disjunct sites in recent assessments. Earlier recovery work recorded 31 sites, while later assessments identified about 37 sites.
  • More than 20 additional subpopulations have been found since the estimate of about 5,000 individuals was made in 2000, but the current national population size remains uncertain.
  • The overall population trend is decreasing. Some subpopulations have declined or been lost following development, habitat loss, inappropriate grazing and low population size.
  • Genetic differentiation can occur between sites separated by only a few kilometres, indicating very limited gene flow.

Habitat: Vegetation and structure

Pygmy bluetongues occupy remnant open grasslands and grassy woodland with a sparse overstorey, provided the soil remains intact and can support burrowing spiders. Habitat can look degraded above ground but still be unsuitable if ploughing, compaction or poor drainage has removed stable burrows.

Known sites are predominantly native temperate grasslands, sometimes with a sparse overstorey of trees. Recorded plant communities include spear grasses, wallaby grasses, brush wire grass, iron-grass and bluebush communities.

  • Important vegetation includes Austrostipa, Rytidosperma or Austrodanthonia, Aristida behriana, Lomandra, Maireana and Ptilotus species.
  • Open inter-tussock spaces are needed for basking, prey detection and movement around burrow entrances.
  • Moderate surrounding grass cover is generally preferred to completely bare ground or dense, matted vegetation. Recent work found occupied burrows were more often close to vegetation and had less bare ground than suitable unoccupied burrows.
  • Tall trees and dense shrubs are generally unsuitable within occupied grassland. Burrows under trees can fill with soil and debris, and canopy can reduce basking opportunities.

Habitat: Soil, topography and climate

The species is most often found in intact, hard-packed, free-draining soils that allow trapdoor and wolf spiders to construct persistent burrows. Grey-brown or red calcareous soils are commonly associated with higher abundance, and lithosol soils can also support the species.

  • Lower slopes of hillsides are important because soils and spider burrows are often deeper there.
  • Tilled fields are unsuitable even where burrows occur immediately beside an occupied grassland patch. The lizards do not move into burrows in tilled soil.
  • Sites occur in areas with approximately 400 to 600 mm annual rainfall. The wider recorded range includes mean annual rainfall of about 365 to 632 mm.
  • Poorly drained or shallow soil is unsuitable where it prevents spiders from making stable burrows.

Foraging habitat: Diet and feeding method

The pygmy bluetongue is mainly a sit-and-wait predator. It forages from the entrance of its burrow and makes short movements into nearby grassland to ambush prey.

Grasshoppers are the main recorded prey. Other food includes ants, small spiders, beetles, snails and cockroaches. Soft plant material is also eaten, including Dianella seed and material from Medicago and possibly chenopods.

  • Plant material becomes a larger part of the diet as summer progresses, so food availability can change through spring and summer.
  • The lizard usually waits at or near the burrow entrance and makes short forays to capture passing invertebrates.
  • A high abundance of arthropods and open spaces between tussocks support efficient prey detection and capture.
  • Pesticide use can reduce prey availability and may expose lizards to poisoned insects or snail bait.

Foraging habitat: Foraging area

The species normally remains close to its home burrow outside the breeding season. Published sources describe short movements to stalk prey, defecate, bask and return to shelter.

  • The source documents do not provide a fixed foraging radius. Survey and management should therefore treat the grassland immediately around occupied and apparently suitable burrows as foraging habitat.
  • Recent microhabitat work assessed a 20 cm by 20 cm area around burrow entrances because lizards spend most of their time within very close range of the burrow.
  • Suitable foraging structure includes tussocks with inter-tussock gaps, moderate vegetation cover and intact soil with nearby spider burrows.

Breeding habitat: Breeding biology

Breeding occurs in the same open grassland habitat used by adults, but reproductive success depends on access to stable burrows, prey and suitable vegetation structure. Young initially remain in the maternal burrow before dispersing to smaller burrows.

The species is viviparous. Mating takes place in spring, when males leave their burrows and search for females. Females give birth in late summer to early autumn, with most births recorded in February.

Mating: October and November

Births: Late January to late March, with most births in February

Litter size: 1 to 4 young

Gestation or incubation: The source documents do not give a confirmed gestation length. The species gives birth to live young.

Age at maturity: Males can reproduce in their second spring. Females may reproduce then, although some first reproduce a year later. Other sources report first breeding at about 2.5 years.

Wild lifespan: Estimated at about 9 years

Captive lifespan: At least 18 years has been recorded in captivity

  • Females give birth inside or at the entrance of a shelter burrow, and young remain in the parental burrow for 1 to 12 weeks.
  • Juveniles then disperse to smaller burrows of their own. Young and adults need a supply of suitable burrows within the grassland.
  • Reproductive output is low and fewer than 10 per cent of juveniles are estimated to survive to adulthood.
  • Polygyny has been recorded, with females accepting matings from multiple males. This can increase genetic mixing within a subpopulation.

Breeding habitat: Breeding habitat features

Breeding habitat is open native grassland with intact, free-draining soil, suitable spider burrows and enough arthropod prey to support females and growing young.

  • Moderate grazing can maintain open spaces between tussocks, but heavy grazing can collapse burrows, reduce vegetation cover and lower reproductive output.
  • Females in moderately grazed paddocks have produced more yolk sacs and given birth earlier than females in hard-grazed paddocks.
  • Late summer and early autumn are sensitive periods because young leave maternal burrows and establish their own smaller shelters.

Sheltering habitat: Natural burrows

Spider burrows are the main shelter resource and are used for refuge, basking, thermoregulation, ambush feeding and protection from predators, fire and high temperatures. Because the lizards generally cannot construct their own burrows, damage to burrows can remove habitat even when the grassland vegetation remains.

Pygmy bluetongues use vacant burrows made by mygalomorph trapdoor spiders and lycosid wolf spiders. Blakistonia aurea is an important burrow builder near Burra. Mouse burrows may also be used where entrance dimensions are similar.

  • Burrow entrances are inconspicuous, circular and usually about 20 to 25 mm in diameter.
  • Burrows range from about 10 to 75 cm deep. Adults generally prefer deeper burrows, often deeper than 20 cm, while juveniles use narrower and shallower burrows.
  • A recent study recorded a mean depth of about 248 mm for occupied burrows and about 178 mm for apparently suitable unoccupied burrows.
  • Only one adult lizard is normally found in a burrow. The lizard usually makes no obvious modification apart from slight bevelled wear at the entrance.
  • Occupied burrows are often near vegetation and may be angled. Recent sampling found a mean distance to the nearest vegetation of about 56 mm for occupied burrows, compared with about 75 mm for suitable unoccupied burrows.

Sheltering habitat: Artificial shelters and survey precautions

Artificial burrows can provide temporary shelter and can assist recruitment or translocation, but they do not replace the need for burrowing spiders and stable natural soil.

  • Artificial burrows should be designed and installed by, or with advice from, the relevant recovery or threatened species team.
  • Do not excavate, fill, compact or drive over natural burrows. Excavation can kill lizards, destroy the burrow and remove a limiting habitat resource.
  • A fibre-optic endoscope of 8 mm diameter or less is the preferred method for checking burrows during authorised surveys.
  • Pitfall trapping is less effective than burrow inspection and installing pit buckets can damage spider burrows.

Threats: Clearing, construction and soil disturbance

The main project risks are direct loss of native grassland, destruction of spider burrows and fragmentation of occupied sites. A small amount of disturbance can have a large effect because subpopulations are small, isolated and slow to recover.

Ploughing, ripping, excavation, grading, trenching, heavy vehicle access and soil compaction can directly kill lizards and spiders, destroy burrows and make the soil unsuitable for new burrows. A single ploughing event can remove the original population even if the paddock later regenerates.

  • Avoid all clearing and ground disturbance in known, historical and potential habitat until a targeted assessment has been completed.
  • Keep roads, access tracks, turbine pads, buildings, services, drainage works and laydown areas out of occupied grassland and areas with suitable spider burrows where practicable.
  • Construction runoff and sediment can enter burrows. Changes in runoff or drainage can alter soil structure, vegetation density and burrow persistence.
  • Infrastructure can divide subpopulations and restrict the short-distance movements needed for mating, juvenile dispersal and movement between burrows.
  • All known populations are considered important. Do not assume that a small or apparently isolated patch has low conservation value.

Threats: Grazing, vegetation and fire

Heavy grazing and stock concentration can destabilise soil, collapse burrows, reduce prey and expose lizards to predators. Conversely, removing grazing without a replacement management approach can produce dense vegetation and reduce basking and foraging spaces.

  • Maintain a moderate grazing regime where it is already compatible with the site, and prevent hard grazing, stock camping and watering points near burrows.
  • Avoid planting trees or dense shrubs in occupied or potential open grassland habitat.
  • Avoid broadscale herbicide, insecticide, fertiliser and toxic snail bait use near habitat. These products can reduce prey, promote weeds, harm burrowing spiders or directly poison reptiles.
  • Fire effects depend on timing and intensity. Avoid burning in spring when males are mobile and in late summer or early autumn when juveniles disperse.
  • Deep burrows can protect adults from fire, but fire can reduce prey and vegetation and can kill lizards caught outside their burrows.

Threats: Fragmentation, predators, disease and collection

Cropped land, roads and development separate most sites. Natural movement between many subpopulations is unlikely, and genetic exchange is limited. Foxes, cats and domestic dogs may prey on lizards, while brown snakes and birds of prey are natural predators.

  • Plan works to retain links between occupied grassland patches where these can be established without disturbing existing burrows.
  • Illegal collection is an increasing risk because the species has a high value in overseas reptile markets. Digging out animals destroys their burrows and can make a site unusable.
  • An ectoparasitic mite, Ophiomegistus michaeli, has been recorded from the species. The fitness effects are not yet known, so hygiene and permit requirements should be followed during handling and translocation.
  • Do not disclose exact locations to unverified people, and report suspected digging, poaching or unauthorised handling to the relevant South Australian authorities.

Survey methodology: 1. Inspect spider burrows with a fibre optic endoscope

Survey this species by locating and inspecting the spider burrows it uses, rather than relying on visual searches or broad trapping. Surveys must be led by an ecologist familiar with pygmy bluetongue identification, burrow ecology and the permits required in South Australia.

Search remnant native grassland and grassy woodland with open tussocks, inter tussock spaces, intact hard packed soil and round spider burrow entrances. Prioritise free draining grey brown or red calcareous soils, lithosol soils and lower hill slopes where burrows may be deeper.

Inspect likely burrows with a fibre optic endoscope no more than 8 mm in diameter and a portable light source. Confirm the occupant without excavating the burrow.

Record each burrow location, occupancy, burrow condition, entrance diameter, approximate depth, surrounding vegetation and any disturbance from machinery or stock.

Treat spider burrows as a limiting habitat resource. Do not probe, widen, collapse or excavate them unless an approved capture or research procedure requires it.

Recommended inspection equipment: Fibre optic endoscope with a diameter of 8 mm or less, and a portable light source

Typical burrow depth: 10 to 75 cm, with adults generally preferring deeper burrows

Typical entrance diameter: Approximately 20 to 25 mm

  • Search systematically across all native grassland and potential habitat within the impact area, including areas that appear degraded but retain intact soil and spider burrows.
  • Mark occupied burrows and suitable unoccupied burrows for protection during project planning and construction.

Survey methodology: 2. Time surveys for activity and detection

Plan primary detection work for the warmer active period. The species is most active above ground around spring and early summer, with males more likely to leave burrows during the November breeding season.

Use November to December surveys when project timing allows, because this is the peak active season identified in the survey guidance. End of summer and autumn surveys can detect adults and juveniles in or near burrows after juvenile dispersal.

Avoid relying on a February pitfall survey. The survey guidance reported nil pitfall captures during February, compared with 1.3 lizards per 100 trap days during the November to December peak active period.

Allow more than one survey period where a single visit may not detect the species, where weather or drought has reduced activity, or where the project could affect a large or fragmented area.

Breeding period: Mating occurs in October and November, with males particularly mobile in spring

Birth period: Late January to late March, with most births in February

Peak pitfall period in the survey guidance: November to December

  • Survey in suitable weather when lizards can bask and forage, and record temperature, rainfall, wind, cloud cover and recent grazing or fire.
  • Use repeat visits when the first survey finds suitable habitat but no lizards, because the species is secretive and usually remains close to its burrow.

Survey methodology: 3. Use trapping only as a supplementary method

Do not use pitfall trapping as the primary detection method. The species rarely moves far from its burrow, and digging in pitfall buckets can damage the spider burrows on which it depends.

If trapping is authorised and required, use a design prepared by the project ecologist and approved under the relevant animal ethics and wildlife permits. Position equipment away from occupied and suitable burrows wherever practicable.

Capture from a burrow only under an approved procedure and by authorised personnel. The survey guidance describes fishing with an insect tied to fine fishing line as a capture method, but this must not be attempted without the required approvals and animal welfare controls.

Reported pitfall result: 1.3 lizards per 100 trap days during November to December, and nil during February

Preferred detection method: Inspection of spider burrows with a fibre optic endoscope

  • Keep traps shaded, check them at the frequency specified in the approved method, and release or transfer animals promptly under the approved protocol.
  • Use close-up photographs and expert verification for any new locality record, and lodge supporting evidence with the South Australian Museum or the relevant state authority.

Survey methodology: Minimum effort and reporting

  • Have a suitably experienced ecologist assess all native grassland, grassy woodland and intact soil that could support spider burrows before finalising the survey design.
  • Inspect all accessible suitable burrows in the proposed disturbance footprint and in any adjoining area where construction may cause soil disturbance, vibration, runoff or altered grazing.
  • Repeat surveys where detection conditions were poor, where suitable burrows remain uninspected, or where the species is found during works and the impact area must be reassessed.
  • Map occupied burrows, suitable unoccupied burrows, native grassland patches, access routes and proposed exclusion areas in the project geographic information system.
  • Submit confirmed records, including negative survey information where required, to the relevant South Australian wildlife database and the Australian Government species records system.
  • Report any suspected poaching, dug-out burrows or unauthorised handling to the relevant South Australian wildlife authority and project environmental officer.

Before habitat disturbance: Avoid and minimise habitat loss

Treat all known, historical and potential habitat as important because the species has a small, fragmented distribution and depends on intact soil and spider burrows. Avoid soil disturbance first, then reduce the area, duration and intensity of any unavoidable impact.

Habitat features to retain: Suitable spider burrows, open native grassland, tussock grasses, inter tussock spaces and intact free draining soil

Dispersal capacity: Limited; females commonly move less than 20 m, although movements up to 200 m have been recorded

Known site context: Most known sites are small, disjunct patches on private agricultural land

  • Redesign the project to retain native grassland, intact soil profiles, spider burrows, tussock grasses and inter tussock spaces.
  • Do not plough, rip, trench, grade, compact or store materials on occupied or potentially suitable habitat.
  • Retain free draining grey brown or red calcareous soils and lithosol soils, particularly on lower hill slopes where deeper spider burrows may occur.
  • Retain moderate vegetation structure around burrows, including tussock grasses and nearby vegetation, while avoiding dense weed growth and heavy accumulations of dead vegetation.
  • Do not plant trees or large shrubs in retained pygmy bluetongue habitat, because the species is associated with open grassland and burrows under trees can fill with soil and debris.
  • Maintain connections between retained grassland patches where practicable. The species has limited dispersal and most sites are separated by cropped or otherwise unsuitable land.

Before habitat disturbance: Check approvals and plan the works

National listing: Endangered under the EPBC Act

South Australian listing: Endangered under the National Parks and Wildlife Act 1972

  • Check whether the proposal must be referred under the Environment Protection and Biodiversity Conservation Act 1999 because the species is listed as Endangered nationally.
  • Obtain all required South Australian permits for surveys, capture, marking, handling, translocation or release under the National Parks and Wildlife Act 1972.
  • Confirm whether native vegetation, threatened ecological community, development or land clearance approvals also apply to the site.
  • Prepare a species specific fauna management plan that identifies occupied burrows, no-go areas, access routes, machinery controls, stop-work triggers, authorised handlers, release sites, incident contacts and reporting requirements.
  • Schedule soil disturbance outside spring and early autumn where practicable, because males are mobile in spring and juveniles disperse in late summer and early autumn.
  • Stage works so that retained habitat remains connected and construction does not isolate occupied burrows or leave animals exposed between cleared areas.

Before habitat disturbance: Prepare and mark the site

  • Complete the pre-clearance survey before vegetation removal, access formation, trenching, earthworks or changes to grazing pressure.
  • Mark occupied burrows, suitable unoccupied burrows, retained grassland and no-entry areas on the ground and in construction plans.
  • Install exclusion fencing where it can protect habitat without crossing burrow entrances or causing stock, machinery or runoff to concentrate beside the retained patch.
  • Keep vehicles, plant, spoil, fuels, wash water and construction materials outside retained habitat and away from burrow entrances.
  • Inspect fencing and marked areas each day before work starts and after heavy rain, vehicle movements or any change to the work footprint.
  • Brief all contractors on the species, its small burrow entrances, the stop-work procedure and the prohibition on collecting or disturbing animals.

During habitat disturbance: Daily work controls

Use a controlled exclusion and observation process during works. The fauna spotter catcher must work with the operator and environmental officer so that machinery does not enter marked habitat or continue after a lizard, burrow or unexpected habitat feature is found.

  • Hold a daily pre-start briefing covering the approved work area, marked burrows, exclusion fencing, access routes, authorised handlers and stop-work triggers.
  • Check the work zone and exclusion fencing before machinery starts, with particular attention to small round spider burrow entrances that may be missed from a vehicle.
  • Keep plant on approved access tracks and previously disturbed ground wherever possible.
  • Prevent spoil, sediment, concrete wash water, fuel, herbicide, fertiliser and other contaminants from entering retained grassland or burrows.
  • Use a spotter to watch the ground immediately ahead of machinery during vegetation removal, trenching, grading and other soil disturbance.
  • Keep construction noise, vibration and vehicle movements away from retained burrows wherever the approved fauna management plan requires it.

During habitat disturbance: Fauna spotter catcher and machinery procedure

  • The fauna spotter catcher must have the required South Australian authority and any project specific approvals before handling a lizard.
  • The spotter catcher must remain in communication with the machine operator and direct the operator to stop before any marked or suspected burrow is approached.
  • Stop machinery immediately if a lizard, occupied burrow, burrow-making spider or previously unmapped suitable burrow is found within the work area.
  • Do not excavate a burrow to remove a lizard unless the approved method specifically permits it and the authorised handler is present.
  • Use an approved capture method and place the animal in a secure, ventilated container only for the shortest period needed for assessment or authorised relocation.
  • Relocate a healthy animal only under the approved plan, to suitable retained habitat nearby with appropriate burrows and vegetation, and record the release location.

During habitat disturbance: Finds, injuries and stop-work triggers

  • Stop work and establish an exclusion area if a pygmy bluetongue is found, if a burrow is damaged, or if the approved impact area needs to expand.
  • Do not handle the animal by untrained staff, contractors or members of the public, and do not retain it as a specimen or pet.
  • Place an injured animal in a quiet, secure container and arrange prompt assessment by an authorised wildlife carer or veterinarian through the project environmental officer.
  • Do not release an injured animal or move a healthy animal across cropped land, roads or other unsuitable ground.
  • Stop work if machinery collapses, fills, exposes or excavates a burrow, or if soil movement, runoff or stock access threatens retained burrows.
  • Record the date, time, location, animal condition, burrow condition, action taken, handler, release or treatment location, photographs and the machinery or activity involved.

After habitat disturbance: Complete post-clearance checks

The project remains responsible for retained habitat and fauna controls after the active construction phase. Check that burrows, soil structure and grassland condition have not been damaged and that the approved mitigation measures are operating.

  • Inspect the entire disturbance boundary and retained habitat for collapsed, filled, excavated or compacted spider burrows.
  • Check for lizards in the work area and along access routes after machinery has left, using a fibre optic endoscope for suitable burrows where authorised.
  • Remove temporary materials, spoil, fencing and equipment from retained habitat without driving over burrows or disturbing intact soil.
  • Repair drainage, sediment controls and exclusion fencing so that runoff does not erode soil or enter burrows.
  • Document all habitat loss, burrow damage, animal encounters, relocations, injuries, deaths and departures from the approved method.

After habitat disturbance: Monitor retained and restored habitat

Useful monitoring indicators: Occupied burrows, suitable unoccupied burrows, burrow condition, vegetation cover, inter tussock spaces, soil condition and lizard detections

  • Continue monitoring occupied burrows and suitable unoccupied burrows at the frequency and duration set in the fauna management plan or approval conditions.
  • Use the same burrow inspection method and mapping system across monitoring visits so that changes in occupancy and burrow condition can be compared.
  • Monitor vegetation structure, inter tussock spaces, weed cover, soil compaction, erosion, grazing pressure and the availability of spider burrows.
  • Increase monitoring or implement corrective action if occupied burrows are lost, burrow availability declines, vegetation becomes dense or bare ground increases around burrows.
  • Keep access controls, exclusion fencing and machinery restrictions in place until the environmental officer confirms that the area no longer presents a project related risk.

After habitat disturbance: Close out approvals and offsets

  • Provide the regulator and approval holders with the required survey, incident, relocation, mortality, rehabilitation and monitoring reports.
  • Submit confirmed species records and updated spatial data to the relevant South Australian wildlife database and other required government repositories.
  • Review whether residual impacts remain after avoidance, minimisation, rehabilitation and approved conservation measures.
  • Implement any required offset, conservation agreement, habitat protection or translocation commitment under the approval conditions.
  • Protect sensitive location data from public release where disclosure could increase the risk of poaching or burrow excavation.

Rehabilitation actions: Restore soil and grassland structure

Rehabilitation should recreate open native grassland with intact, stable soil and a continuing supply of spider burrows. Artificial burrows can assist short term recruitment or translocation, but they do not replace burrowing spiders as the long term source of shelter.

Recorded habitat plants: Austrostipa, Rytidosperma, Lomandra, Aristida, Maireana and Ptilotus species are associated with known habitat

Preferred soil setting: Free draining grey brown or red calcareous soils, and some lithosol soils, with intact profiles

  • Reinstate intact, free draining soil profiles and prevent compaction, tilling, ripping and repeated vehicle access across the rehabilitation area.
  • Restore an open grassland structure with tussocks and inter tussock spaces suitable for basking, foraging and spider burrow construction.
  • Use locally appropriate native tussock and grassland species recorded from pygmy bluetongue habitat, including Austrostipa, Rytidosperma, Aristida, Lomandra, Maireana and other native perennial grasses and herbs suited to the site.
  • Do not establish trees or dense shrubs in the restored grassland.
  • Control weeds with low disturbance methods and avoid broadscale herbicide use where spot treatment or grazing management can achieve the required result.
  • Do not apply fertiliser unless specifically approved, because nutrient addition can encourage weeds and alter native grassland composition.

Rehabilitation actions: Re-establish burrow resources

Artificial burrow role: A supplementary and generally short term measure for recruitment and translocation

Recent microhabitat findings: Occupied burrows were associated with angled burrows, more nearby vegetation and less bare ground, rock and lichen

  • Protect and encourage burrowing spiders by retaining stable, undisturbed soil and avoiding practices that collapse or erode their burrows.
  • Install artificial burrows only under an approved species management plan, preferably where natural burrows already occur and soil and drainage conditions are suitable.
  • Use artificial burrows as a short term supplement for recruitment or an authorised translocation, not as the sole basis for long term population stability.
  • Place artificial burrows in microhabitats with nearby vegetation and limited bare ground, while considering the recent finding that occupied burrows were more often angled and closer to vegetation.
  • Do not place artificial burrows where they will flood, be trampled by stock, be covered by dense litter or be exposed to repeated machinery movements.

Rehabilitation actions: Manage grazing, fire and predators

Preferred grazing approach: Moderate grazing may maintain open grassland, while heavy grazing is detrimental

Fire periods to avoid: Spring and early autumn

  • Maintain moderate grazing where it is part of the established management regime and helps keep inter tussock spaces open.
  • Prevent heavy grazing, stock trampling and concentrated stock access that can destabilise soil and collapse burrows.
  • Do not remove grazing automatically from a site where it currently controls weeds and maintains suitable open grassland structure; assess the effect on the species first.
  • Avoid planned burning in spring and early autumn when males and dispersing juveniles are more likely to be above ground.
  • Manage foxes and cats where an approved predator control programme identifies a project related risk, while retaining native predators as part of the natural system.
  • Prevent dogs and unauthorised people from entering restored habitat and protect sensitive locations from collection and burrow excavation.

Rehabilitation actions: Measure rehabilitation success

  • Inspect and map occupied and suitable unoccupied burrows at the same seasons and with the same method used for the baseline survey.
  • Measure whether native tussock cover, inter tussock spaces, soil stability, weed cover and burrow availability are moving towards the approved rehabilitation objectives.
  • Record lizard occupancy, juvenile detections, adult detections, burrow condition, grazing pressure, fire events, predator control and any use of artificial burrows.
  • Use the monitoring results to adjust grazing, weed control, erosion controls, access restrictions, artificial burrows or translocation measures.
  • Continue monitoring until the environmental officer and relevant regulator agree that the restored habitat is stable and no longer presents a project related risk.

Sources