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Australian Lungfish (Neoceratodus forsteri)

The Australian Lungfish is a large, ancient freshwater fish found mainly in the Mary and Burnett river systems of south-eastern Queensland, with other translocated populations in Queensland waterways. Works near rivers, dams and weirs can affect shallow, weed-covered spawning and nursery habitat, block adult movement, or disturb eggs and young. It is Vulnerable under the Commonwealth EPBC Act and in Queensland, and is protected from fishing under Queensland law.

Conservation status

Commonwealth, EPBC Act 1999: Vulnerable.

Queensland, Nature Conservation Act 1992: Vulnerable.

Breeding season

Australian Lungfish breeds annually from August to December in south eastern Queensland. Spawning may begin in early August in some years and small numbers of eggs may still be present in December, so timing varies between rivers, sites and years.

Breeding mode: External fertilisation. Pairs circle near weed banks, and the male fertilises eggs as they are released.

Breeding frequency: Annual breeding has been recorded.

Egg laying sites: Eggs are laid separately and attached to aquatic vegetation or roots in shallow water with dense plant cover. The species does not build a nest.

Clutch size: Up to hundreds of eggs in the wild. Captive clutches of 200 and 500 to 600 eggs laid at one time have been reported.

Egg care: Adults do not guard the eggs and do not appear to care for the young.

Incubation period: Not recorded.

Age at maturity: Estimated at 15 years for males and 20 years for females.

Timing varies between years and regions, with records of breeding beginning in early August at Enoggera Reservoir and occasional late egg laying in December in the Brisbane River.

  • Spawning and egg laying: Spawning occurs from August to December, usually beginning while daylength is increasing.
  • Eggs and young in aquatic plant cover: Eggs and young require shallow water with dense macrophyte cover, such as ribbon weed or other aquatic plants.
  • Adult movement to spawning habitat: Adults need access to suitable spawning areas, and barriers can prevent movement to remaining breeding sites.
  • Adult presence and nocturnal activity: Adults are present year round, with activity reported to be greatest around midnight.
  • Highest clearing risk: Clearing, plant removal, disturbance, flooding or access barriers are most likely to affect spawning sites, eggs and young from August to December.

Identification: Appearance and size

The Australian Lungfish is a large, heavy-bodied freshwater fish with broad, flipper-like fins and five pairs of gills. It can breathe air through a lung, but it normally lives in water and should be handled with care during surveys or rescue work.

The body is robust and elongate, with large overlapping scales. The dorsal, caudal and anal fins form a broad fin along the rear of the body.

Adults are generally olive-green, brown or almost black above, with an orange, yellow, pink or white underside. Juveniles are often darker and mottled, with a more prominent rounded head and obvious sensory pores on the snout.

Gills: Five pairs

Fins: Broad, flipper-like fins with no fin spines

  • Adults can grow to more than 1.5 m in length.
  • Historical records include weights of up to 40 kg.
  • A sample of almost 3000 fish ranged from 345 to 1420 mm, with a mean total length of 906 mm.

Identification: Calls and behaviour

The species is not identified by echolocation. During the breeding season, air breathing may be frequent and can be accompanied by a distinct loud burp with the fish's lips clear of the water.

Pairs may circle close to weed banks at the water surface during breeding. These observations can help field teams recognise activity near spawning habitat.

  • Look for large, slow-moving fish close to weed beds, river margins and roots.
  • Do not approach or handle fish unnecessarily, especially near dense aquatic vegetation.

Identification: Similar species and field signs

No similar Australian fish species are identified in the available identification information. The combination of a large heavy body, broad joined rear fin, lobed or flipper-like paired fins and air-breathing behaviour is distinctive.

Eggs are generally laid separately and attached firmly to aquatic vegetation or roots by a sticky outer coating. The species does not build a nest and does not guard its eggs.

  • Large fish moving slowly near aquatic plants or submerged roots.
  • Separate eggs attached to vegetation or roots.
  • No nest, mound, burrow, whitewash, droppings or characteristic odour.
  • A loud burp at the water surface during the breeding season.

Distribution: Current natural range

Living Australian Lungfish populations are concentrated in south-eastern Queensland. The species is mapped in Queensland and New South Wales, but the current living distribution described for Australia is in Queensland, while New South Wales is known for important fossil records.

The generally accepted natural, self-sustaining range is the Mary River system and Burnett River system in south-eastern Queensland. Core populations occur in the main channels of these rivers.

The species may also occur in the Brisbane River and North Pine River systems. The origin of some populations in those systems is uncertain because translocations occurred historically.

Australian state with current living range: Queensland

Main region: South-eastern Queensland

  • Mary River system, including parts of the main channel and tributaries.
  • Burnett River system, including parts of the main channel and some tributaries.
  • Brisbane River and North Pine River systems, where populations may be natural or translocated.

Distribution: Translocated populations

Translocated or established populations have been recorded in several Queensland waterways and impoundments. Presence and persistence can vary between sites, so local records should be checked before works begin.

  • Condamine River.
  • Coomera River.
  • Enoggera Reservoir.
  • Lake Manchester and Gold Creek Reservoir.
  • Lake Wivenhoe, Lake Somerset and parts of the Brisbane River system.
  • North Pine River and Lake Samsonvale.

Distribution: Site planning

On a Queensland construction site, treat any large lungfish record as significant, whether it is from a natural river population, an impoundment or a historically translocated population.

The species is associated with fewer than ten locations in some assessments and has an estimated area of occupancy of less than 2000 km². Confirm records with the relevant Queensland authority and assess possible impacts under both Commonwealth and Queensland requirements.

  • Check records for the whole river system, not only the immediate work area.
  • Include upstream and downstream habitat when assessing barriers, dewatering or changes to flow.
  • Do not assume that a dam or reservoir population is expendable because it may be translocated.

Habitat: River and impoundment habitat

Australian Lungfish use permanent freshwater rivers, creeks, dams and weirs. Adults may feed in impoundments, but successful breeding and nursery habitat is usually in shallow water with dense aquatic plant cover.

Look for the species in permanent-flow river channels, creek mouths, backwaters and reservoir margins. Adults can use deep impounded water for feeding, including dams and weirs.

Core habitat in the Mary and Burnett systems includes main river channels. Some tributaries and impoundments also support fish, but habitat quality can vary substantially between sites.

  • Permanent freshwater channels.
  • Shallow river margins and low-velocity areas.
  • Reservoir and weir margins used by adults.
  • Aquatic plant beds, submerged roots and vegetated banks.

Habitat: Features to map before works

Map aquatic vegetation, shallow benches, submerged root masses, river crossings, weirs, barrages and other structures. Record the connection between these features and the main channel.

Dense vegetation is especially important where eggs or young fish may be present. Juveniles are difficult to sample and may be missed in open water surveys.

  • Ribbon weed and other dense submerged macrophytes.
  • Shallow water with slow or moderate current.
  • Fine sand or gravel near spawning vegetation.
  • Continuous passage around crossings, weirs and temporary works.

Habitat: Hydrology and habitat condition

Breeding habitat can be lost when water infrastructure floods shallow areas, causes fluctuating water levels or removes aquatic plants. Silt deposition and plant removal can alter the suitability of otherwise established spawning beds.

Assess changes in water level, flow, turbidity, sediment deposition and aquatic plant cover before approving in-stream or bank works.

  • Identify areas that would be inundated by a temporary or permanent change in water level.
  • Avoid unnecessary removal of aquatic plants and submerged roots.
  • Maintain water quality and flow connectivity through the work area.
  • Inspect both upstream and downstream areas for changes caused by barriers or altered flows.

Foraging habitat: Where adults may feed

Adults use rivers, dams and weirs as feeding habitat. The available ecological information does not define a reliable field diet for this species, so site assessments should focus on protecting the aquatic habitat used by adult fish rather than relying on prey observations.

Look for adults in main river channels, deeper pools, reservoir margins and around structures that retain water. Adults have also been recorded at night in thick para grass growing in shallow water beside the shore.

Feeding areas may overlap with movement routes and breeding habitat. Avoid assuming that deep or open water has no value simply because it lacks aquatic plants.

  • Main river channels and deep pools.
  • Dams, weirs and reservoir margins.
  • Shallow vegetated shorelines.
  • Areas around submerged roots, banks and channel edges.

Foraging habitat: Competition and introduced fish

Exotic and translocated native fish may compete with adult lungfish for breeding habitat. Exotic Tilapia, Oreochromis mossambica, are believed to prey on lungfish eggs and young.

Record introduced fish observed during aquatic surveys and report them through the relevant aquatic fauna and fisheries channels. Do not move fish, water, mud or equipment between sites without appropriate hygiene controls.

  • Inspect equipment before moving between waterways.
  • Remove fish from nets and traps before sampling another site.
  • Include aquatic weeds, water quality and introduced fish in site condition assessments.

Foraging habitat: Survey considerations

The Australian Lungfish is nocturnal, with maximum activity reported around midnight. Angling observations may therefore be more productive at night, but any method must comply with permits, animal ethics requirements and Queensland fishing restrictions.

Electrofishing is generally the most effective sampling method for the species. Use trained operators and follow the Australian Code of Electrofishing Practice.

  • Use experienced fish handlers and minimise handling time.
  • Keep captured fish in water and use aeration where they must be held.
  • Avoid unnecessary night lighting, bank access and vessel activity near vegetated margins.
  • Record all fish species, habitat conditions, location, date, time and survey effort.

Breeding habitat: Spawning habitat

Breeding requires shallow water and dense aquatic plant cover. Eggs are attached to plants or roots, and young fish need similar cover as nursery habitat, so even a small vegetated margin can be important.

Look for shallow, vegetated margins with ribbon weed or other dense macrophytes. Spawning areas may have slow or moderate current, fresh water and fine sand or gravel.

Eggs may be attached from close to the surface to about 1 m deep in Enoggera Reservoir and 1.5 m deep in the Brisbane River. Water levels can fall after eggs are laid, potentially exposing eggs attached high on roots.

Breeding season: Generally August to December

Egg placement: Individually attached to aquatic plants or roots

  • Dense submerged or emergent aquatic vegetation.
  • Submerged roots and stable plant beds.
  • Shallow water beside the main channel.
  • Slow or moderate current without floating debris.

Breeding habitat: Breeding behaviour and nursery areas

Breeding occurs annually. Fish may circle near weed banks before eggs are laid. The female turns on her side while the male entwines around her and fertilises the eggs as they emerge.

There is no nest or parental guarding. Young fish require dense plant cover, and open impoundment water is generally unsuitable nursery habitat.

Estimated maturity: Males about 15 years, females about 20 years

Recruitment: Recent recruitment into the adult population is considered low

  • Treat egg-bearing plants and nearby shallow cover as breeding habitat.
  • Avoid clearing, trampling, anchoring or isolating aquatic plant beds.
  • Maintain access between adult fish and connected spawning areas.
  • Protect nursery cover even when adult fish are not observed.

Breeding habitat: Works controls

Plan in-stream works, bank access and vegetation removal outside the August to December breeding period where possible. If works cannot avoid this period, obtain project-specific aquatic fauna advice and increase inspection of shallow vegetated margins.

Flooding, degrading or significantly disturbing spawning or nursery habitat, disrupting breeding, or restricting adult access to spawning sites may require referral under the EPBC Act.

  • Retain aquatic plants and submerged roots wherever practicable.
  • Keep temporary crossings, cofferdams and barriers away from connected spawning habitat.
  • Maintain fish passage during construction and remove temporary barriers promptly.
  • Stop work and seek advice if eggs, young fish or adult lungfish are found in the work area.

Sheltering habitat: Cover to look for

Specific adult shelter sites are not well defined. Young Australian Lungfish depend on dense aquatic vegetation for cover, and adults may use vegetated margins, submerged roots, deeper pools and river edges.

Inspect dense weed beds, submerged root masses, undercut banks and shallow vegetated edges. These features can provide cover for eggs, juveniles and adults moving along the margin.

Juveniles are not easily sampled and may remain hidden within dense vegetation. A lack of captured juveniles does not demonstrate that nursery habitat is absent.

  • Dense macrophyte beds.
  • Ribbon weed and similar submerged plants.
  • Submerged roots and woody bank structure.
  • Undercut margins and connected shallow water.

Sheltering habitat: Reservoir and river edges

Adults can occur in deeper open water, particularly in dams and weirs, but young fish need plant cover. Steep-sided impoundments with fluctuating water levels generally provide poor spawning and nursery conditions.

Retain connected vegetated margins where work areas meet reservoirs, weirs or river channels.

  • Avoid removing the last dense plant cover from a shoreline.
  • Limit vessel wash, bank disturbance and sediment entry near shallow margins.
  • Keep access routes outside aquatic vegetation where practicable.
  • Inspect dewatered areas for stranded fish before they are isolated.

Sheltering habitat: Handling and temporary isolation

If fish must be moved during approved works, use appropriately qualified personnel and follow the relevant permits and animal welfare procedures. Keep fish in clean, aerated water for the shortest practical period.

Do not relocate an Australian Lungfish to another waterway without specific authorisation. Prevent disease transfer by cleaning and disinfecting equipment between sites.

  • Minimise handling and protect the fish's mucous layer.
  • Support the body fully during any authorised handling.
  • Revive stressed fish in an aerated tank before release.
  • Release fish back into suitable connected habitat as directed by the fauna specialist.

Threats: Flooding and habitat loss

The main development risks are loss of shallow vegetated habitat, altered water levels and flows, barriers to movement, and disturbance during breeding. Long lifespan means poor recruitment may take many years to become obvious in adult numbers.

Dams, weirs and other water infrastructure can flood or reduce shallow spawning habitat. Deep water, steep banks and fluctuating levels generally support feeding adults better than eggs and young fish.

Construction planning should map the full area of spawning and nursery habitat that could be inundated, cleared, dewatered or altered.

  • Avoid permanent loss of shallow aquatic plant beds.
  • Retain nursery vegetation and submerged roots.
  • Assess temporary water-level changes as well as permanent inundation.
  • Control sediment that could smother plants, roots or eggs.

Threats: Barriers and altered flows

Weirs, barrages, temporary crossings, cofferdams and poorly designed culverts can restrict adult movement to spawning sites. Altered flow may also disconnect shallow breeding areas from the main channel.

Maintain passage through and around work areas, and inspect barriers during changing flows and water levels.

  • Provide a clear fish passage plan before in-stream works.
  • Do not leave temporary barriers in the channel after works finish.
  • Avoid isolating shallow vegetated margins from the main river.
  • Assess upstream and downstream effects of water infrastructure.

Threats: Breeding disturbance and direct harm

Clearing aquatic plants, operating machinery in shallow water, dewatering, anchoring and high levels of noise or vibration can disturb breeding fish, eggs and young. Surveys should avoid August to December where possible.

Use a qualified aquatic fauna ecologist for works near confirmed or potential spawning habitat.

  • Schedule vegetation removal and in-stream disturbance outside the breeding season where practicable.
  • Inspect isolated pools and dewatered areas for fish before works proceed.
  • Use soft-start and low-disturbance methods where practicable.
  • Stop work if eggs, juveniles or lungfish are detected in an affected area.

Threats: Introduced fish and cumulative decline

Tilapia may prey on eggs and young, while exotic and translocated native fish may compete for breeding habitat. Habitat loss and low recruitment can combine with these pressures across a river system.

Because adults may live for decades, a site can still contain many adults after breeding habitat has declined. Management should therefore protect recruitment habitat, not only visible adult fish.

Estimated habitat reduction: About 26 per cent of Australian Lungfish breeding and nursery habitat has been lost or reduced

Development status: Vulnerable under the EPBC Act and in Queensland

  • Record introduced fish and report significant observations.
  • Prevent transfer of fish, water, sediment and aquatic weeds between waterways.
  • Protect connected breeding and nursery habitat at a catchment scale.
  • Refer potentially significant impacts to the relevant Commonwealth and Queensland authorities.

Survey methodology: 1. Desktop assessment

Survey for Australian Lungfish should focus on river channels, shallow aquatic plant beds and areas where barriers may affect access to spawning habitat. The species is long lived, adults can be difficult to detect, and juveniles are particularly difficult to sample in dense vegetation.

Map the Burnett and Mary River systems first, including main channels, tributaries, dams, weirs, barrages and connected wetlands.

Check for recorded or potential populations in the Brisbane, North Pine, Logan, Coomera and Condamine systems, and in connected impoundments or reservoirs.

Identify shallow water with dense macrophytes, ribbon weed, roots and other aquatic plant cover. Treat these areas as potential spawning or nursery habitat.

Map barriers that could restrict adult movement to spawning areas. Review proposed changes to water levels, bed levels, flow, vegetation or connectivity.

Survey methodology: 2. Field detection

Use boat based or backpack electrofishing where conditions and approvals allow. Follow the Australian Code of Electrofishing Practice and use settings that minimise injury and stress.

Electrofishing is generally most effective during the day in areas of low turbidity. Avoid damaging aquatic vegetation and shallow spawning beds.

Use angling or structured angler surveys as an additional method. Australian Lungfish are nocturnal, with activity reported to peak around midnight, so night sampling may improve detection.

Use visual searches from the bank or boat where water is clear. Inspect dense vegetation for juveniles, but recognise that young fish are not easily sampled.

Do not rely on a single visit to conclude that the species is absent. Repeat sampling across suitable habitat and, where needed, across more than one date or water condition.

Survey methodology: 3. Survey timing and conditions

Avoid intrusive surveys from August to December where possible, because this is the known spawning period.

If work during the spawning period cannot be avoided, use the least intrusive method available and obtain ecological advice before entering shallow vegetated habitat.

Record water level, flow, turbidity, weather, water temperature where measured, aquatic vegetation, substrate, access barriers and recent disturbance.

Give particular attention to slow or moderate flow beside aquatic plant beds. Eggs may be attached to vegetation or roots from close to the surface to about 1.5 m deep.

Survey methodology: 4. Records and handling

Record observers, dates, times, methods, effort, locations, GPS points, maps, habitat condition, all fish captured and survey limitations.

Photograph the fish and habitat where this can be done without prolonged handling. Record length and any identifying marks using approved procedures.

Use appropriately qualified and authorised handlers. Keep fish in water and out of their habitat for the minimum time possible.

Use aerated containers and revive fish before release. Handle fish as little as possible to protect the mucous layer.

Remove all fish from nets and traps before moving to another site to reduce disease transfer.

Before habitat disturbance: 1. Approvals and permits

Plan works around aquatic habitat, not only around the location of adult fish. Avoid shallow vegetated spawning and nursery areas, maintain adult access, and confirm Commonwealth and Queensland requirements before any disturbance begins.

Refer the action under the EPBC Act if it may significantly impact Australian Lungfish, including by flooding, degrading or substantially disturbing spawning or nursery habitat, disrupting breeding, or restricting adult access to spawning sites.

Do not start an action that is likely to have a significant impact without the required EPBC Act approval.

Confirm Queensland requirements with the relevant fisheries and environment authorities. Australian Lungfish are protected from fishing, and collection for research, education or aquaculture requires the relevant permit.

Obtain a species management program where required for tampering with a breeding place or otherwise interfering with protected wildlife. Confirm whether the proposed activity needs a Queensland permit, authority or other approval before mobilisation.

Check local waterway, fisheries, animal ethics and handling requirements for electrofishing, angling, capture, relocation and release.

Before habitat disturbance: 2. Avoidance and site controls

Redesign works to avoid shallow water with dense aquatic plant cover, especially in the Burnett and Mary River main channels and other known or potential breeding areas.

Maintain passage between adult habitat and suitable spawning areas. Do not place temporary crossings, cofferdams, screens, rock structures or spoil in a way that blocks movement.

Avoid changing water levels, flow, bed form or aquatic vegetation unless the impact has been assessed and approved.

Do not clear aquatic plants or roots from potential spawning habitat without a site specific ecological assessment and the required authority.

Use marked exclusion areas around aquatic vegetation, spawning habitat and access routes. Set the limits with the aquatic ecologist and approval conditions because no universal Australian Lungfish buffer is specified.

Before habitat disturbance: 3. Pre-clearance inspection

Complete a targeted inspection immediately before works in or beside the waterway. Search shallow vegetated margins, roots, weed beds, slack water and areas with slow or moderate current.

Look for adult fish, juveniles and eggs attached to vegetation or roots. Australian Lungfish do not build nests, so inspect the vegetation itself rather than searching for a constructed nest.

If eggs, juveniles or adults are found in an affected area, stop the relevant works and obtain advice from the aquatic ecologist and approval authority before proceeding.

Document the inspection, habitat condition, water level, flow, vegetation, photographs, GPS points and the names of the personnel involved.

Before habitat disturbance: 4. Timing and induction

Schedule instream disturbance outside August to December where practicable. Treat this as a risk reduction measure, not as permission to disturb breeding habitat.

Allow for adult movement to spawning areas because movement timing and migration distances are not well defined.

Induct all workers on identification, habitat triggers, exclusion areas, pollution controls, stop work authority and the reporting chain.

Give the spotter catcher or aquatic fauna supervisor authority to stop work when a fish, eggs, suitable breeding habitat or an unexpected barrier risk is identified.

Keep fuels, concrete washout, sediment, spoil and contaminated water away from the channel and aquatic plant beds.

During habitat disturbance: 1. Sequential clearing

Use a staged, low impact approach. The aquatic fauna supervisor should control searches, handling and release, and should stop work whenever the approved controls no longer protect fish, eggs, habitat or movement routes.

Clear terrestrial areas first and work progressively toward the waterway only where this is allowed by the approval and method statement.

Use a staged approach that allows fish to move away from the work area. Do not herd or trap fish against temporary barriers.

Inspect each work section before disturbance and after plant movement, dewatering or water level changes.

Keep aquatic vegetation, roots and shallow margins intact unless removal is specifically approved.

During habitat disturbance: 2. Stop work triggers

Stop the affected activity if an Australian Lungfish is found in the work area, if eggs are found attached to vegetation or roots, or if juveniles are found in dense aquatic cover.

Stop if a previously unrecorded shallow vegetated spawning area is exposed, flooded, isolated or damaged.

Stop if a temporary structure, dewatering activity or sediment control measure restricts adult access or creates a fish stranding risk.

The aquatic fauna supervisor must assess the situation and obtain advice from the aquatic ecologist and relevant authority before work resumes.

During habitat disturbance: 3. Handling and relocation

Allow fish to leave naturally wherever possible. Do not capture or relocate Australian Lungfish unless the method is approved and the people involved are authorised.

Use suitable equipment, aerated water and the shortest practical handling time. Do not lift fish by the fins or leave them exposed on dry surfaces.

Do not move eggs or disturb attached vegetation unless directed by an approved relocation or rescue procedure.

Release any authorisedly relocated fish into suitable connected habitat approved by the aquatic ecologist and authority. Record the release location and conditions.

During habitat disturbance: 4. Injured or stranded animals

Stop work and keep machinery, people and dogs away from the animal.

Contact the project ecologist, aquatic fauna supervisor and the relevant wildlife or fisheries authority. Use an authorised wildlife carer or veterinarian where required.

Keep the fish in clean, aerated water while awaiting direction. Do not administer treatment or release an injured fish without approval.

Record the location, condition, apparent cause, photographs, actions taken and final outcome.

During habitat disturbance: 5. Daily records

Record all sightings, captures, eggs, juveniles, injuries, mortalities, relocations, habitat disturbance and stop work events.

Record the time, location, method, personnel, water conditions, equipment used, release details and any approval or incident number.

Update the site map each day to show exclusion areas, disturbed habitat, access routes and areas requiring further inspection.

After habitat disturbance: 1. Immediate post-clearance check

Post-clearance checks should confirm that no fish, eggs or suitable aquatic habitat have been isolated or damaged. Keep the records needed to demonstrate compliance and to improve controls during later work stages.

Inspect the completed work area, temporary structures, dewatered sections, pools, vegetation edges and downstream margins.

Check for stranded fish, trapped juveniles, exposed eggs, blocked movement routes, damaged macrophytes, sediment deposition and changes in water quality.

Remove approved temporary barriers and restore fish passage as soon as the work method allows.

Do not enter or alter a suspected breeding area without the required approval and ecological direction.

After habitat disturbance: 2. Monitoring and reporting

Complete any monitoring required by the approval, species management program, construction environmental management plan or aquatic fauna plan.

Use repeat inspections or targeted sampling where the project may affect recruitment, aquatic vegetation, spawning habitat or adult access.

Report all incidents, mortalities, injuries, unauthorised disturbance, failed controls and unexpected habitat impacts to the project manager and relevant authorities within the required timeframe.

Include maps, photographs, survey effort, weather and water conditions, fish observations, handling details, corrective actions and outstanding risks.

After habitat disturbance: 3. Relocated animals

Confirm that every authorisedly relocated fish was released at the approved location and in suitable water conditions.

Record identification details where available, release coordinates, date, time, water conditions, habitat and the people responsible.

Undertake follow-up checks where required by the approval or where relocation was used because of dewatering, isolation or a construction incident.

Do not assume that a released fish has survived without the monitoring required by the approved method.

After habitat disturbance: 4. Review and adaptive management

Hold an environmental close-out review with the aquatic ecologist, spotter catcher, site supervisor and project manager.

Compare actual impacts with the approved risk assessment. Review whether exclusion areas, timing, dewatering, sediment controls and stop work procedures were effective.

Update the work method before the next stage if fish were found, habitat changed, movement was restricted or handling controls were inadequate.

Retain the records so future surveys and construction planning can account for long lived adults and delayed evidence of poor recruitment.

Rehabilitation actions: 1. Restore aquatic habitat

Rehabilitation should restore connected freshwater habitat and the plant cover needed for spawning and nursery use. Focus on function, flow and aquatic vegetation rather than installing structures that suit other fauna groups.

Reinstate shallow water, gentle margins and suitable aquatic plant cover where these were approved rehabilitation targets.

Use locally appropriate aquatic plants, including suitable macrophytes such as ribbon weed where recommended by the aquatic ecologist.

Restore natural or approved flow paths and remove temporary barriers that restrict adult movement.

Stabilise banks without hardening shallow spawning margins or covering roots and aquatic vegetation with rock, spoil or sediment.

Rehabilitation actions: 2. Manage water quality and weeds

Prevent sediment, concrete, fuels, nutrients and contaminated water from entering the channel during rehabilitation.

Control invasive aquatic and riparian weeds using methods approved for the waterway and avoid removing native spawning or nursery vegetation.

Inspect plantings after changes in water level and flow. Replace failed vegetation where the approved rehabilitation objective requires it.

Keep machinery out of shallow vegetated habitat wherever practicable.

Rehabilitation actions: 3. Do not use unsuitable replacement structures

Do not install nest boxes, bat boxes, artificial nests or roost structures for Australian Lungfish. The species does not build a nest and does not use terrestrial roost or maternity structures.

Do not substitute artificial structures for shallow aquatic spawning habitat and dense macrophyte cover.

If a project proposes an artificial aquatic habitat feature, obtain species specific advice and approval first. Design it to restore natural aquatic function, not to imitate a nest or roost.

Rehabilitation actions: 4. Lighting and construction legacy

Limit night lighting over the waterway, shallow margins and aquatic plant beds. Direct lights away from the channel and use the lowest practical intensity and duration.

Remove redundant temporary access tracks, crossings, pipes, screens and barriers that could affect movement or water levels.

Check that rehabilitation has not created isolated pools, abrupt water level changes, fish traps or new barriers.

Rehabilitation actions: 5. Long term monitoring

Monitor aquatic vegetation, water depth, flow, bank stability, barriers, fish passage and evidence of use by adults or juveniles.

Schedule monitoring outside the main August to December spawning period where this can be done without reducing the ability to detect habitat problems.

Use repeatable locations and methods, and include additional targeted fish surveys where the project affected spawning or nursery habitat.

Continue monitoring for the period required by the approval and extend it if vegetation fails, barriers persist or recruitment concerns remain.

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