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Olive Python (Liasis olivaceus)

The Olive Python, Pilbara subspecies, is a large, primarily nocturnal python restricted to rocky ranges, gorges, drainage systems and waterholes in north-western Western Australia. It is listed as Vulnerable under the EPBC Act and in Western Australia, so clearing, road construction, mining, gas infrastructure and changes to surface water or groundwater need site-specific controls where suitable habitat occurs.

Conservation status

Commonwealth, EPBC Act 1999: Vulnerable.

Western Australia, Biodiversity Conservation Act 2016: Vulnerable.

Breeding season

Olive Pythons mate mainly from May to July. Egg laying and hatching dates vary between Pilbara field guidance and broader species records, so clearing controls should protect rocky refuges, drainage and water-associated habitat from winter through the hatchling period.

Reproductive mode: Egg laying

Clutch size: 12 to 40 eggs

Incubation: About 50 days

Size at hatching: About 35 centimetres

Age at maturity: 3 to 4 years reported; another source gives 2 to 5 years

Nest or egg sites: Depressions in the ground, crevices, rocky caves and abandoned termite mounds are reported shelter or possible egg-site features; specific wild nest sites are not confirmed

Breeding frequency: Not recorded

Confirm timing locally before clearing, as rainfall, temperature, water availability and habitat condition can shift movement, shelter use, breeding and hatching dates.

  • Mating: Mating is reported from May to mid-July, with Pilbara field guidance placing breeding in June to August. The sources do not establish a peak month.
  • Gravid females: Females are expected to carry eggs after mating and before laying. This period is inferred from mating in May to July, reported laying in September and October, late spring laying records, and an 81 to 85 day interval after mating.
  • Egg laying: Captive species records report laying in September and October, while other species accounts describe laying in late spring, which includes October and November in Australia. Pilbara-specific laying dates are not confirmed.
  • Incubation: Eggs are reported to incubate for about 50 days. On the reported September to November laying window, eggs may remain in nests from September through January.
  • Hatchlings: Captive species records report hatching in January and February. A Pilbara-specific emergence period is not established, although a 50 day incubation after late spring laying could produce some earlier hatchlings.
  • Active period: Olive Pythons are mainly nocturnal and can be active throughout the year. Day activity is reported in spring and autumn, while warmer periods are associated with increased movement near water and rocky outcrops.
  • Winter inactivity: During the cooler Pilbara months, especially June to August, individuals use caves and rock crevices and may remain away from water. Adults may bask at cave entrances or on north-facing cliffs in the morning.
  • Highest clearing risk: Risk is highest from June to August because breeding activity overlaps with increased use of caves and crevices. Risk remains elevated from September to February where clearing affects eggs, gravid females or hatchlings, and during warmer periods when animals move through connected rocky habitat, drainage and water-associated areas.

Identification

This is a large, heavy-bodied python with a fairly uniform olive to olive-brown colour. Identification on development sites should be confirmed by an experienced reptile ecologist, particularly where the animal is seen briefly at night or in poor light.

The body is dull olive-brown to pale fawn, or dark olive to olive-brown with a pearly sheen. The belly is white or cream. The lips are pale and finely dotted with pale grey or brown. The species has pitted scales along the front edge of the lips and smooth mid-body scales.

Typical length: 2.5 to 4 metres

Reported weight: 5 to 15 kilograms

Colour: Uniform olive, olive-brown or yellowish brown, often with a pearly sheen

Belly: White to cream

Identification: Distinguishing features

The Pilbara form differs from northern olive python populations in mid-body and ventral scale counts. Smith's original distinction used 58 to 63 mid-body scale rows and 374 to 411 ventral scales for the Pilbara form, compared with 61 to 72 mid-body rows and 355 to 377 ventral scales for northern populations.

The Pilbara subspecies can be confused with other large Australian pythons when seen at a distance. Colour, body size, locality and habitat are useful field clues, but scale counts or genetic confirmation may be needed for difficult records. The supplied sources do not provide a simple field key separating it from every other large python in its range.

Identification: Field signs and handling records

Look for a large, unpatterned sloughed skin at rocky outcrops, caves and other shelter sites. Sloughed skins are usually olive or plain coloured and have a high number of scales around the middle of the body, more than 30, compared with elapid skins.

Scats may contain recognisable fur, feathers, bones, teeth or claws. They have a large white, cakey uric acid component and several cylindrical sections. Record the exact location of skins, scats, live animals and likely shelter entrances, because direct observations are uncommon and the species is cryptic.

There are no calls, nests, tracks or eyeshine features identified in the supplied sources as reliable field signs. Do not handle or relocate an animal unless this is undertaken under the project's fauna management procedure by an appropriately authorised person.

Distribution

The Olive Python occurs across northern Australia, but the listed Pilbara subspecies is confined to Western Australia. Records are scattered because the snake is cryptic and reliable trapping or census methods are not available.

The species occurs in Western Australia, the Northern Territory and Queensland. The Pilbara subspecies is restricted to the Pilbara and northern Ashburton areas of Western Australia, separated from northern populations by the Great Sandy Desert.

The known Pilbara range extends from near Port Hedland south to Newman and the Mount Augustus area, and west and south-west through the Ashburton region. It extends east to the Ragged Hills and Oakover River drainage, with isolated coastal and island populations including the Burrup Peninsula and Dolphin Island.

Australian states and territory: Western Australia, Northern Territory and Queensland for the species overall

Pilbara subspecies range: Pilbara and northern Ashburton regions of Western Australia

Elevation: Recorded across all elevations in the species' overall range

Bioregional context: The Pilbara form occurs within the Pilbara and Gascoyne regional areas and the Rangelands Natural Resource Management Region

Distribution: Known strongholds and occurrences

Known Pilbara locations include Pannawonica, Millstream, Tom Price, Newman, Yandi, the Hamersley and Chichester ranges, the Burrup Peninsula, Dampier Archipelago islands, Mount Augustus and drainage systems associated with the Coongan, Shaw, Yule, Harding, Fortescue, Ashburton and Robe rivers.

The subspecies has been recorded at about 21 locations in the Pilbara. A sub-adult was recorded on the proposed Pardoo iron ore shipping facility site, about 70 kilometres east of Port Hedland. Part of the range is protected in Karijini National Park.

Reported Pilbara locations: About 21 locations in the 2008 conservation advice

Protected areas mentioned: Karijini National Park, with additional olive python range within protected areas elsewhere in northern Australia

Distribution: Population information

A reliable total population estimate and population trend are not available. The species is difficult to census because it is cryptic, trapping and census methods are unreliable, and surveys have covered only a limited part of the range.

Some remote populations are described as sizable in pockets and less exposed to threatening processes. Genetic work found low genetic diversity in the sampled Pilbara population and a low estimated effective population size, but the authors noted that the estimate may reflect localised sampling.

Population estimate: Not available

Population trend: Unknown

Genetic survey: 25 Pilbara and 22 Kimberley olive pythons were sampled

Estimated effective population size: Ne = 5 for the sampled Pilbara group, compared with Ne = 160 for the sampled Kimberley group; the Pilbara estimate may reflect localised sampling

Habitat

The Pilbara subspecies is associated with rocky country and water, but it also uses adjacent dry ranges and riverine vegetation. Suitable habitat can therefore extend beyond the immediate edge of a mapped waterhole or gorge.

Preferred habitat includes deep gorges, rocky ranges, caves, rock crevices, large quiet rock pools, permanent or semi-permanent waterholes and drainage systems. The python also occurs in monsoon forest, savanna woodland, coastal plains, dry shrubland and grassland across the species' broader range.

In the Pilbara, important settings include rocky areas near seasonally dry watercourses, permanent waterbodies in rocky ranges, riverine vegetation and localised drainage. At Pannawonica and Millstream, animals may use riverine vegetation and then move into adjacent stony ranges.

Habitat: Structural features

Retain rocky outcrops, gorge walls, caves, crevices, boulder piles, waterholes, drainage lines, river margins and connected stony ranges. The Burrup population uses extensive rock piles vegetated with spinifex and nearby spinifex grasslands, even though large waterbodies are absent.

Map habitat as a connected unit rather than treating a waterhole or drainage line as an isolated feature. The species may shelter away from water in cooler months and move close to water and rock outcrops in warmer months.

Burrup habitat: Rock piles with spinifex, adjacent spinifex grasslands and small semi-permanent pools

Water dependence: Waterholes are used for hunting, but winter shelter sites may be away from water

Climate and elevation: Occurs from sea-level settings to all elevations across the overall species range

Foraging habitat

The Olive Python is an ambush predator that hunts along animal trails, near water and from submerged positions in pools. Foraging habitat includes both water-associated sites and nearby rocky or stony country used during movements.

Recorded Pilbara prey includes rock-wallabies, fruit bats, ducks, Spinifex Pigeons and coucals. The broader species account also records mammals, birds and other snakes. The available sources do not identify particular food plants because this species is carnivorous.

Prey is captured by ambush on animal trails or by striking from a submerged position in waterholes. The python is an adept swimmer and may forage in pools, along drainage lines, beside riverine vegetation and around rocky outcrops.

Foraging method: Ambush on animal trails or strike from a submerged position in waterholes

Recorded prey: Rock-wallabies, fruit bats, ducks, Spinifex Pigeons, coucals, mammals, birds and other snakes

Foraging habitat: Waterholes, pools, drainage lines, riverine vegetation, rocky outcrops and adjacent stony ranges

Foraging habitat: Movement while foraging

Radio-telemetry and field observations indicate wider movement during warmer months, usually close to water and rock outcrops. The Burrup population has large home ranges and may move vast distances.

No general foraging-distance or home-range estimate is available. Project surveys should therefore inspect connected drainage, rocky and stony habitat beyond the immediate location of a record.

Breeding habitat

Breeding information for the Pilbara subspecies is limited. The available Pilbara field guidance places breeding in the cool months and identifies males travelling between suitable areas to find mates.

Breeding habitat is likely to include connected rocky range, gorge, drainage and water-associated habitat that provides shelter and access to prey. Avoid separating rocky refuges from adjacent drainage and riverine vegetation during the breeding period.

The sources do not provide a confirmed Pilbara clutch size, incubation period, age at maturity or wild lifespan. The species-wide IUCN account reports egg laying in September and October and hatching in January and February, but this timing is not confirmed as Pilbara-specific and differs from the Pilbara survey guidance, which reports breeding in June to August.

Pilbara breeding season: June to August

Mating movement: Males may travel up to 3 kilometres in search of mates

Egg laying and hatching: For the species overall, captive records report laying in September and October and hatching in January and February; not confirmed for the Pilbara subspecies

Clutch size: Not stated in the supplied sources

Gestation or incubation: Not stated for the Pilbara subspecies

Age at maturity: Not stated in the supplied sources

Lifespan: Not stated in the supplied sources

Breeding habitat: Site management during breeding

Before clearing, inspect and map caves, crevices, boulder piles, gorge walls, drainage lines and nearby waterholes within the proposed disturbance area. Use an experienced reptile ecologist where habitat is suitable, because animals may remain hidden and direct searches have low detection rates.

Where breeding habitat cannot be avoided, apply staged clearing and fauna handling controls specified in the project approval or management plan. Do not rely on a single negative daytime search to demonstrate absence.

Sheltering habitat

Shelter is provided mainly by caves, rock crevices and rocky outcrops. Shelter locations can be away from water, particularly during the cooler months.

During winter, individuals have been recorded hiding in caves and rock crevices away from water sources. In cooler weather adults may bask at cave entrances or on north-facing cliffs in the morning.

On the Burrup Peninsula, shelter is associated with extensive rock piles vegetated with spinifex. In other parts of the Pilbara, likely shelter features include gorge walls, boulder fields, rock outcrops and crevices near drainage systems.

Known refuge types: Caves, rock crevices, cave entrances, rocky outcrops, gorge walls and boulder piles

Seasonal shelter use: Greater use of caves and crevices during cooler winter months

Known refuge dimensions: No den, cave or crevice dimensions are provided in the supplied sources

Sheltering habitat: Signs at refuges

Search rocky outcrops and shelter entrances for plain-coloured sloughed skins and scats. A skin may be identified by its olive colour, lack of pattern and high number of mid-body scales. Scats may contain fur, feathers, bones, teeth or claws and a conspicuous white uric acid component.

Daytime searches of open gorges have been largely unsuccessful in some surveys. During cooler months, targeted searches of north-facing cliffs and cave entrances in the morning can be more productive, while night searches near rocky habitat and permanent water may detect active animals.

Threats: Clearing and construction

The main risks on development sites are loss or disturbance of rocky gorge, drainage and waterhole habitat, loss of prey, road mortality and direct killing. Hydrology and water quality need separate controls because the species uses pools and drainage systems for hunting and movement.

Mining, gas and infrastructure development can destroy or fragment rocky gorge, gully, drainage and waterhole habitat. BHP's Pilbara strategic assessment reported impacts of about 1,123 hectares of suitable gorge and gully habitat plus less than 2 hectares of major drainage habitat at Mining Area C South flank, and 34 hectares of suitable major drainage and gorge or gully habitat for the Jimblebar optimisation project.

Avoid clearing known populations, caves, crevices, rocky outcrops, drainage lines, riverine vegetation and surface-water pools. Keep construction laydown, access tracks, borrow areas, spoil placement and night lighting away from these features where practicable.

Reported Mining Area C South flank impact: About 1,123 hectares of suitable gorge and gully habitat and less than 2 hectares of major drainage habitat

Reported Jimblebar impact: 34 hectares of suitable major drainage and gorge or gully habitat

Relevant development types: Mining, gas infrastructure, roads, rail, port facilities and associated construction

Threats: Water, roads and fire

Manage groundwater drawdown, dewatering, altered runoff, sedimentation, pollution and changes to water-table levels. These changes can affect pools, drainage systems, prey and movement routes. The BHP program specifically identified Weeli Wolli Spring, Coondiner Pool, Ben's Oasis, Koodaideri Spring and Punda Spring as waterholes requiring protection from physical disturbance and adverse hydrological change.

Road traffic can cause deliberate or accidental killing, particularly as industry and tourism increase. Use warning signs and fauna speed controls where records or suitable habitat occur. The supplied sources do not identify a species-specific fire regime or fire threshold, so avoid burning or clearing shelter and prey habitat without site assessment.

Threats: Predators, prey loss and persecution

Feral cats and foxes prey on Olive Pythons, particularly juveniles. Foxes also reduce prey such as quolls and rock-wallabies. Maintain predator control and protect prey habitat around known populations.

Some animals are killed after being mistaken for venomous brown snakes. Train workers and spotter catchers to identify the species, maintain a no-kill response, and use an approved capture and relocation procedure where relocation is authorised.

Threats: Survey and monitoring limits

A single daytime search is not sufficient to demonstrate absence. The species is cryptic, largely nocturnal and may shelter in inaccessible rock features. Use habitat assessment, targeted night driving near rocky areas and permanent water, winter searches of north-facing cave entrances, and searches for skins and scats.

Population size, distribution and trend remain poorly known. Record all observations and signs with coordinates, photographs, habitat descriptions and the outcome of any fauna interaction.

Survey methodology: 1. Confirm habitat and records

Survey for the Pilbara olive python should focus on rocky gorges, ranges, drainage lines, riverine vegetation, waterholes, caves and rock piles in the Pilbara and northern Ashburton regions of Western Australia. The species is cryptic, mostly nocturnal and difficult to detect, so survey design must account for habitat, season, weather and the limits of negative results.

Before selecting methods, map rocky ranges, gorges, caves, rock outcrops, drainage lines, waterholes, riverine vegetation, semi-permanent pools and adjacent stony ranges.

Check government databases, museum records, previous environmental reports and local knowledge for records within and near the project area.

Treat suitable habitat as potentially occupied where survey results are insufficient to demonstrate absence, particularly because reliable population census methods are not available.

Known range: Pilbara and northern Ashburton regions of Western Australia, including areas near Port Hedland, Newman, Mt Augustus, Nanutarra, Tom Price, Millstream, Burrup Peninsula and adjacent islands.

Typical size: Approximately 2.5 to 4 metres according to the survey guidelines; the conservation advice describes growth to 2.5 metres.

Survey methodology: 2. Night driving and spotlighting

Drive project roads and accessible tracks at night through rocky areas near permanent water, drainage lines and riverine vegetation.

Use a slow, consistent search speed and record the route, start and finish times, weather, temperature if available, visibility, moon phase and search conditions.

Search from shortly after dark into the early hours, because the species is almost entirely nocturnal and may remain active until around sunrise.

Give particular attention to road edges, vehicle tracks, animal trails, rock outcrops, gullies and waterhole margins where a python may be moving or hunting.

A rate of one python per two nights of night driving is possible at exceptional locations in suitable weather, but this is not a guaranteed detection rate or a standard effort requirement.

Preferred timing: Nocturnal surveys, with activity commonly extending from shortly after dark to the early morning.

Best conditions: Suitable weather when pythons are active, with attention to warmer conditions and areas near water.

Survey methodology: 3. Winter basking and shelter searches

During cooler winter months, inspect north-facing cliffs, cave entrances, rock crevices and other daytime shelter sites for basking or resting pythons.

Search near water and in adjacent rocky ranges, because individuals may shelter away from water during winter and move more widely near water during warmer months.

Do not rely on walking open gorges in the morning alone, because this approach has been reported as largely unsuccessful.

Use experienced personnel who can distinguish an olive python from other snakes and who can work safely around caves, cliffs and unstable rock.

Breeding period: June to August in the survey guidelines.

Winter behaviour: Individuals may become more sedentary and bask near cave entrances or shelter in caves and rock crevices.

Survey methodology: 4. Signs and supplementary searches

Inspect rocky outcrops, caves, rock piles and sheltered areas for sloughed skins and faecal pellets where direct sightings are unlikely.

Record a sloughed skin as a possible detection only after checking its features, including uniform colour, lack of pattern and more than 30 scales around the middle of the body compared with elapid skins.

Record faecal pellets that have a large white, cake-like uric acid portion and cylindrical sections containing hard prey remains such as fur, feathers, bones, teeth or claws.

Use these signs to target follow-up night surveys, especially on the Burrup Peninsula and other areas without large waterbodies.

Do not use trapping or aquatic survey effort unless a qualified herpetologist has designed it for the site, because the supplied species guideline does not provide a standard trapping method for this python.

Survey methodology: Minimum effort and reporting

  • Use a habitat-based survey design that combines nocturnal road or track searches with targeted inspections of rocky shelters, cave entrances, water margins and signs.
  • Document the exact survey effort, including the number of nights, hours searched, kilometres driven or walked, areas covered, personnel, weather and detection conditions.
  • Repeat surveys when conditions are unsuitable or when the project contains extensive suitable habitat that was not effectively searched.
  • Record every live animal, carcass, skin, faecal sign and incidental observation with date, time, coordinates, habitat description, photograph and observer details.
  • Submit verified records to the relevant Western Australian wildlife database and provide records to the project regulator or approval agency as required.
  • Retain negative survey results with maps and effort details, rather than reporting only that the species was not detected.

Before habitat disturbance: Avoid and minimise habitat loss

The Pilbara olive python uses rocky gorges, caves, drainage lines, waterholes, riverine vegetation and adjacent stony ranges. Avoidance and careful staging are preferred because the species has low recorded genetic diversity, an uncertain population size and no reliable census method.

Key habitat: Deep gorges, waterholes, rocky ranges, caves, rock crevices, drainage systems, riverine vegetation and adjacent stony ranges.

Known project risk: Gas, mining and infrastructure development can destroy habitat, alter hydrology and increase road traffic.

  • Avoid clearing occupied habitat and retain rocky gorges, cave and crevice shelter, rock piles, waterholes, drainage lines, riverine vegetation and connected stony ranges.
  • Keep surface water pools and drainage features intact where practicable, including the surrounding access routes and shelter used by pythons.
  • Design roads, infrastructure and work areas to avoid known records, repeated detection locations and habitat supporting prey such as rock-wallabies and other vertebrates.
  • Maintain movement connections between waterholes, drainage lines, riverine vegetation, rocky ranges and shelter sites.
  • Do not assume that rehabilitation will replace the function of established rocky or wetland habitat during the construction period.

Before habitat disturbance: Approvals and planning

  • Check whether the action may significantly impact the EPBC Act listed Pilbara olive python and obtain project-specific environmental advice before clearing.
  • Confirm Western Australian threatened fauna requirements, permits, licences and fauna handling authorisations before works begin.
  • Prepare a fauna management plan that identifies habitat, survey results, exclusion zones, stop-work triggers, authorised handlers, relocation procedures, injury response and reporting requirements.
  • Plan works to avoid the cooler-month shelter and basking period from June to August where practicable, while recognising that the species may be active outside this period.
  • Stage clearing so that retained habitat remains connected and fauna can move away from the active work area without being funnelled towards roads or machinery.

Before habitat disturbance: Pre-clearance preparation

  • Complete a pre-clearance survey using the methods in this profile and inspect all proposed disturbance areas, access tracks, laydown areas and service corridors.
  • Mark retained gorges, caves, crevices, rock piles, waterholes, drainage lines, riverine vegetation and known records on construction plans and on the ground.
  • Fence or otherwise delineate exclusion areas where this can protect retained habitat without blocking python movement between shelter and water.
  • Brief all operators and fauna spotter catchers on the species’ appearance, non-venomous status, likely habitat and the site-specific stop-work procedure.
  • Inspect machinery, stockpiles, pipes, culverts and materials for sheltering snakes before moving or loading them.

During habitat disturbance: Daily controls and machinery interface

Works must be supervised so that machinery does not enter retained habitat or continue operating when a python or important habitat feature is at risk. The fauna spotter catcher should have authority to pause work and should work within the limits of their licence, training and project approval.

  • Conduct a daily pre-start inspection of the work area, access routes, stockpiles, pipes, culverts, rock piles and machinery for pythons or signs.
  • Keep the fauna spotter catcher in a position where they can see the active clearing face and communicate directly with the operator.
  • Clear vegetation and surface material in stages, allowing the spotter catcher to inspect each section before machinery advances.
  • Use low-speed, controlled movement around rocky shelter, drainage lines, waterholes, caves, crevices and riverine vegetation.
  • Stop machinery immediately when the spotter catcher identifies a python, another snake that cannot be safely identified, an occupied shelter or an unexpected water feature.
  • Prevent workers from chasing, cornering, striking, handling or photographing a python at close range.

During habitat disturbance: Habitat feature handling

  • Avoid disturbing caves, crevices, rock piles, rocky outcrops, drainage lines and waterholes unless the approved action requires it and the feature has been inspected.
  • Do not roll, crush or move large rocks, logs, culverts, pipes or other potential shelters without a fauna spotter catcher present.
  • Keep cleared material and spoil out of drainage lines and waterholes, and prevent sediment, pollutants and altered runoff from entering retained pools.
  • Where a habitat feature must be removed, inspect it from a safe position, dismantle it progressively and allow the fauna spotter catcher to check each stage.
  • Retain suitable rocks, logs and natural shelter material for approved rehabilitation or habitat enhancement where they can be stored without creating a fauna hazard.

During habitat disturbance: If a python is found

  • Stop work in the immediate area and establish a safe exclusion zone that prevents people, vehicles and machinery from approaching the animal.
  • Notify the fauna spotter catcher supervisor and the project environmental officer, and follow the approved fauna handling and relocation procedure.
  • Do not attempt to handle, restrain or relocate the python unless the person is authorised, trained and equipped under the relevant approval and Western Australian requirements.
  • Allow the python to move away naturally where it can do so safely and where the movement will not take it towards machinery, roads or people.
  • If relocation is authorised and necessary, move the animal only to nearby retained habitat with suitable rocky shelter, drainage or water features, and record the release location.
  • Obtain advice from a wildlife veterinarian or appropriately authorised wildlife carer for an injured animal, and transport it only by an authorised person using approved methods.
  • Treat a dead or injured python as a reportable fauna incident and retain photographs, coordinates and the circumstances of the incident.

During habitat disturbance: Stop-work triggers and records

  • Stop work when a Pilbara olive python is found within the active work area, when its shelter or movement route may be affected, or when the spotter catcher cannot safely inspect the next clearing section.
  • Stop work when unapproved clearing, hydrological change, sediment discharge, pollution or damage to a retained waterhole or drainage feature occurs.
  • Restart only after the animal or habitat risk has been managed, the spotter catcher and environmental officer have agreed that work can resume, and the event has been recorded.
  • Record the date, time, location, activity, habitat feature, animal condition, photographs, personnel involved, action taken, relocation details and restart approval.
  • Report incidents and any suspected breach of approval conditions to the relevant regulator within the required timeframe.

After habitat disturbance: Post-clearance checks

Post-clearance work should check that retained habitat, water features and movement connections remain functional. Monitoring and reporting should address both direct fauna incidents and changes caused by altered drainage, groundwater or water quality.

  • Inspect the cleared area, retained habitat edges, access tracks, stockpiles, culverts and water features after clearing and after major rainfall or earthworks.
  • Check for trapped, injured or dead pythons and for new barriers between rocky shelter, drainage lines, riverine vegetation and waterholes.
  • Confirm that exclusion fencing, fauna escape points and other controls remain intact and are not directing animals towards roads or machinery.
  • Remove temporary materials that could trap or shelter fauna unless they are part of an approved habitat design.

After habitat disturbance: Monitoring and adaptive management

Example program method: The BHP program used targeted population surveys at Mining area C South flank every five years from 2018, although the review reported that population data were not available.

  • Continue targeted monitoring at locations with previous records, known habitat and project impacts, using repeat night searches and inspections of shelter sites.
  • Monitor groundwater, surface water, runoff, sediment and pollution where dewatering, water discharge or earthworks could affect waterholes and drainage habitat.
  • Use monitoring results to adjust dewatering, drainage, traffic controls, lighting, fencing and work staging if pythons or their habitat are affected.
  • For large projects, retain a consistent survey method so that records from different years can be compared.

After habitat disturbance: Reporting and offsets

Published BHP example: Mining area C South flank reported 1,123 hectares of suitable gorge and gully habitat and less than 2 hectares of major drainage habitat affected, while the Jimblebar optimisation project reported 33 hectares of major drainage habitat and 1 hectare of gorge and gully habitat.

  • Provide survey, incident, habitat disturbance, hydrology and rehabilitation results in the project environmental report and any approval reports.
  • Report habitat loss in hectares and identify the habitat type affected, including gorge and gully, major drainage, surface water pools and riverine habitat.
  • Where an approval requires offsets, calculate and manage them under the approved plan, and do not treat rehabilitation as a substitute for calculating residual impact unless the regulator has expressly accepted that approach.
  • Publish or submit validation, decision, annual environmental and incident reports where required by the approval or strategic assessment program.

Rehabilitation actions: Restore habitat structure and connectivity

Rehabilitation should restore the linked shelter, water, movement and prey features used by the Pilbara olive python. It will not immediately replace mature rocky habitat, caves or established drainage systems, so avoidance and retention remain the primary measures.

  • Reinstate natural drainage lines, pools and suitable water retention features where they have been disturbed, while avoiding erosion, sedimentation, pollution and artificial barriers to movement.
  • Reconnect retained rocky ranges, gorges, riverine vegetation, waterholes and adjacent stony habitat through the rehabilitation design.
  • Replace or stabilise suitable rocks and natural shelter material where the approved rehabilitation plan identifies a need, without creating unstable piles or hazards to people and machinery.
  • Retain and re-establish native riverine and rocky-range vegetation using locally appropriate Pilbara species and provenance, as specified by the project ecologist and regulator.
  • Do not place artificial hollows or nest boxes as a default measure, because the supplied sources identify caves, crevices and rock shelter rather than tree hollows as the relevant shelter features for this python.

Rehabilitation actions: Manage prey, weeds, predators and fire

  • Control weeds and prevent rehabilitation areas from becoming dominated by non-native vegetation that reduces shelter or prey habitat.
  • Implement approved fox and feral cat control where these predators threaten pythons or their prey, particularly juveniles, quolls and rock-wallabies.
  • Manage fire in accordance with regional and site-specific advice so that rocky shelter, riverine vegetation, prey resources and movement routes are retained.
  • Prevent domestic animals, waste and project activities from increasing predator access to retained and rehabilitated habitat.

Rehabilitation actions: Monitor rehabilitation success

  • Inspect rehabilitated drainage, pools, rocky shelter, vegetation cover, erosion controls and connectivity after construction and during the maintenance period.
  • Use nocturnal searches, winter shelter inspections and searches for sloughed skins and faecal pellets to test whether pythons are using rehabilitated or retained habitat.
  • Measure success against approved indicators such as stable drainage and water quality, no new movement barriers, survival of planted vegetation, control of weeds and predators, and verified python detections where monitoring is required.
  • Continue monitoring until the regulator and project ecologist agree that habitat structure and ecological function are stable and maintenance controls can be withdrawn.

Sources