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Estuary Stingray (Hemitrygon fluviorum)

The Estuary Stingray is a medium-sized, demersal ray of Australian rivers, estuaries, tidal bays and near-shore waters. It can occur in or near clearing and construction sites where works affect mangroves, mudflats, river channels, water quality or fish passage. It is mapped in New South Wales, the Northern Territory and Queensland, and is listed as near threatened in Queensland, where it is protected wildlife and tampering with a breeding place requires a species management program.

Conservation status

Queensland, Nature Conservation Act 1992: Near threatened.

Breeding season

The Estuary Stingray is a non-migratory Australian ray with poorly known breeding timing. No month-specific breeding pattern has been established, so treat suitable estuarine habitat as potentially occupied throughout the year, with local variation between southern New South Wales, Queensland and northern populations.

Breeding mode: Live-bearing ray. The female gives birth to live young, but the reproductive process and timing are not recorded for this species.

Litter size: Not recorded.

Gestation: Not recorded.

Breeding sites: Not recorded. Suitable habitat includes shallow estuaries, mangrove-fringed rivers, tidal bays and adjacent near-shore waters.

Age at maturity: Males mature at 7 years and 41 cm disc width. Females mature at 13 years and 63 cm disc width.

Size at birth: Young have been reported at about 11 cm disc width, equivalent to about 35 cm total length.

Breeding frequency: Not recorded.

Local observations, water temperature, flooding, salinity and habitat condition may shift activity between years and regions, so repeat surveys and seasonal site records should guide project timing.

  • Potential breeding activity: No breeding months are known, so mating and birth may occur at different times between regions and years.
  • Young present in estuarine habitat: Young are not readily assigned to a season, so shallow rivers, mangroves and estuaries should be treated as potential nursery habitat year round.
  • General estuarine activity and presence: The species uses estuaries, lower river reaches, mangrove habitats and near-shore waters, with no documented seasonal migration period.
  • Highest clearing risk: Because breeding timing and nursery locations are unresolved, plan clearing, dredging and in-water works on the basis that rays and young may be present in every month.

Identification: Appearance and size

The Estuary Stingray is a medium-sized, flattened ray with a broad disc and a long tail. It is poorly known and can be confused with other rays, so unusual records should be photographed and checked by an experienced elasmobranch specialist.

Use the common name Estuary Stingray when reporting a confirmed record. Adults can reach at least 93 cm disc width, and museum records include larger individuals. It is a demersal species that spends much of its time on or near the bottom.

Do not rely on colour alone. Several similar rays occupy the same shallow coastal and estuarine habitats. Avoid close approach and do not attempt to handle a live ray unless this is part of an authorised procedure.

Maximum size: 93 cm disc width on the fish profile, with museum records reporting up to 120 cm disc width

Maximum estimated age: 21 years

Body form: Medium-sized, demersal ray

  • Record the location, waterbody, tide, depth and substrate where the animal was seen.
  • Take photographs from above where this can be done safely, including the whole animal and the tail.
  • Do not photograph or measure an animal by restraining it on the bank or in shallow water.

Identification: Similar species and identification risk

The species has been confused with Himantura species, Dasyatis thetidis, the freshwater whipray Himantura dalyensis and other undescribed or poorly resolved rays. Northern Australian records in particular require care because some historical records were reassigned after review.

Records from the Northern Territory and northern Queensland should be checked carefully. A photograph alone may not always resolve the identification.

  • Do not assume every estuarine stingray in northern Australia is an Estuary Stingray.
  • Seek specialist advice for records from Darwin, the Gulf of Carpentaria, Cape York or other areas where similar rays occur.

Identification: Calls and field signs

The Estuary Stingray has no recognised call or echolocation system used for field detection. It is generally detected visually, by capture records or by underwater cameras.

Feeding and resting may leave shallow pits or depressions in sandy or muddy substrates. Pits are not diagnostic because other rays can create similar marks, and rays may also make depressions when burying themselves to rest.

  • Look for the animal on bare sand or mud, particularly in shallow sheltered water.
  • Treat feeding pits as evidence of ray activity, not as confirmation of this species.
  • Do not expect droppings, nests, whitewash, odour or vocal cues to assist with detection.

Distribution: State and regional range

The Estuary Stingray is endemic to Australia. Its confirmed eastern Australian range extends from the Hacking River in central New South Wales to Repulse Bay in central Queensland, while current species profiles also map it in the Northern Territory and across wider northern Australian waters.

In New South Wales, records include the far south coast at Wagonga Inlet, the Hunter and Hawkesbury systems, Sydney Harbour, Botany Bay, Brisbane Water, Wallis Lake, the Clarence River and other coastal rivers and estuaries. The species is now uncommon in parts of New South Wales compared with historical records.

In Queensland, records include southern Queensland bays and estuaries, Moreton Bay, the Brisbane, Noosa, Maroochy, Mooloolah, Mary, Nerang and Tallebudgera systems, Hervey Bay, Port Curtis, Mackay and Repulse Bay. Moreton Bay and Hervey Bay are likely population centres, and the species remains locally abundant in some southern Queensland estuaries.

The species is mapped in the Northern Territory, including Darwin. Some northern records have been questioned or reassigned because similar rays were misidentified, so field records from this region should be verified.

  • New South Wales, including coastal rivers, estuaries, bays and harbours.
  • Queensland, especially southern Queensland bays and estuaries, with records extending north to Repulse Bay.
  • Northern Territory, including Darwin, with identification requiring particular care.

Distribution: Range context for site work

The species has a patchy distribution and is strongly associated with sheltered coastal and estuarine environments. A site without a recent record should not automatically be treated as free of the species, particularly where suitable mangrove, mudflat, bare-sand or tidal-river habitat remains.

The centre of abundance appears to be in sheltered bays and estuaries of southern Queensland. Historical range contraction and local declines have been reported in parts of New South Wales and southern Queensland.

  • Check museum, fisheries, local ecological and previous project records before works begin.
  • Map connected waterways, tidal reaches, mangrove margins and shallow flats within and downstream of the project area.
  • Treat records from adjacent waterways as relevant where the project could affect tidal exchange, water quality or aquatic connectivity.

Distribution: Overseas records

The Estuary Stingray is regarded as an Australian endemic. Records from Papua New Guinea, eastern Indonesia and some northern Australian localities attributed to this species have been associated with similar or undescribed rays and should not be used without taxonomic confirmation.

Habitat: Habitat features to map

Look for the Estuary Stingray in shallow, sheltered aquatic habitat rather than exposed open coast. Works near mangroves, tidal rivers, mudflats, bare sandy bottoms, seagrass beds and estuary channels should be planned as potential habitat works.

The species uses mangrove-lined rivers, estuaries, sheltered bays, tidal rivers, lower river reaches and adjacent near-shore marine waters. It can enter freshwater, and has been recorded across a broad salinity range in the Hunter River.

Map the aquatic footprint as well as the bank footprint. Habitat can extend below the ordinary work area, including subtidal flats, channel margins and shallow areas beneath or beside temporary structures.

Depth: 0 to 40 m on the fish profile, with a 20 to 28 m offshore record near the Clarence River mouth

Salinity: Recorded in the Hunter River at salinities from 14 to 35

  • Mangrove fringes and mangrove roots.
  • Shallow muddy or sandy intertidal flats.
  • Bare estuary floors and sheltered bays.
  • Lower river reaches and tidal channels.
  • Seagrass beds and adjacent open-bottom habitat.
  • Near-shore waters connected to the estuary.

Habitat: Substrate and aquatic connectivity

Bare substrates appear to be preferred over seagrass in Wallis Lake. Sand and mud are also used for feeding and resting, and rays contribute to sediment turnover through their movements and feeding pits.

Maintain connection between marine, estuarine and upstream freshwater areas. Culverts, causeways, cofferdams, dewatering and poorly designed crossings can restrict movement or alter the habitat available to aquatic fauna.

  • Avoid filling, isolating or narrowing shallow channels where practicable.
  • Prefer crossings that span the waterway and retain natural bed and banks.
  • Keep temporary instream works to the smallest practical footprint.
  • Check that temporary and permanent structures do not create perched, blocked or excessively fast-flowing sections.

Habitat: Site survey approach

No single field method reliably detects this species in all conditions. Combine records review with visual observations, safe boat or bank-based inspection, underwater cameras where suitable, and consultation with local fisheries or ray specialists.

Survey effort should cover the full aquatic area that may be affected, including shallow flats, mangrove margins, channel edges and downstream receiving waters. Record tide, water depth, substrate, salinity and water clarity whenever practicable.

  • Use remote cameras where direct observation is unsafe or visibility is poor.
  • Repeat observations where a single visit could be affected by tide, turbidity or temporary disturbance.
  • Treat an unidentified ray as a potential Estuary Stingray until checked.

Foraging habitat: Foraging areas

The Estuary Stingray forages on the estuary floor and commonly uses bare sand or mud. Protect bottom habitat, water quality and the small benthic animals that support the species.

In Wallis Lake, Estuary Stingrays preferred bare substrates over seagrass and showed limited interaction with oyster leases. They feed on or near the bottom, and feeding activity can produce shallow pits in sand or mud.

Diet information indicates a role as a secondary consumer. Benthic fish and crustaceans are important components of the diet in Wallis Lake, while shellfish are also reported as prey.

Benthic fish: Estimated 37% of assimilated diet in a Wallis Lake study

Crustaceans: Estimated 28% of assimilated diet in a Wallis Lake study

Trophic position: Upper end of trophic level 3 in the Wallis Lake study

  • Inspect bare sandy and muddy areas for ray activity before dredging or seabed disturbance.
  • Include shallow flats and channel margins in the aquatic habitat assessment.
  • Do not assume an oyster lease or artificial structure is the only relevant foraging area.

Foraging habitat: Construction risks to feeding habitat

Dredging, reclamation, seabed compaction and loss of bare sediment can remove or alter feeding habitat. Increased turbidity and sedimentation can reduce water quality, affect benthic communities and interfere with aquatic fauna.

Pollution from fuels, concrete washout, acid sulfate soils, pesticides, fertilisers and contaminated sediment can affect prey and water quality. Prevent contaminated water from entering connected waterways.

  • Avoid dredging and seabed disturbance where practicable.
  • Use effective erosion and sediment controls before earthworks begin.
  • Keep disturbed banks and beds to the smallest practical area.
  • Inspect and maintain controls after rainfall and during high-flow conditions.
  • Manage dewatering so fish and rays are not trapped, stranded or discharged into unsuitable water.

Foraging habitat: Bioturbation and ecological function

Ray feeding and resting pits can move and aerate sediment. In Brisbane Water, stingrays were estimated to move more than 21,000 tonnes of sand per year, although the reported measurement was for stingrays generally and was not specific to this species.

Avoid treating feeding pits as expendable ground disturbance. Their loss can reduce sediment turnover and affect other estuarine organisms.

  • Photograph and map notable concentrations of ray pits before works.
  • Retain undisturbed areas of suitable bottom habitat beside unavoidable works where practicable.
  • Restore natural bed profile and aquatic habitat after temporary works are removed.

Breeding habitat: What to look for

The breeding places and breeding season of the Estuary Stingray are not well established. Mangrove wetlands and estuaries may support reproduction or young animals, so avoid disturbing suitable shallow habitat and seek advice when pups or repeated ray use are recorded.

No species-specific nest, spawning structure, colony or maternity site has been identified. Young have been reported at about 11 cm disc width, but the locations and timing of birth are not established.

Potentially important areas include shallow mangrove-fringed rivers, sheltered bays, intertidal flats and tidal wetlands connected to deeper water. These features should be retained where practicable even when a breeding place cannot be confirmed.

Male maturity: 7 years and 41 cm disc width

Female maturity: 13 years and 63 cm disc width

Young: Reported at about 11 cm disc width

  • Record small rays, repeated sightings and concentrations of animals.
  • Map mangrove edges, shallow nursery-like areas and access routes between flats and channels.
  • Do not infer that an area is unimportant because no breeding structure is visible.

Breeding habitat: Queensland breeding-place requirements

In Queensland, the Estuary Stingray is protected wildlife. Tampering with its breeding place requires a species management program. Obtain the relevant approvals and ecological advice before disturbing a suspected breeding place, nursery area or repeatedly used shallow habitat.

Where a project may affect a breeding place, document the habitat, proposed disturbance, avoidance measures and any required fauna management actions before clearing or construction starts.

  • Stop and seek advice if pups, repeated use or a concentrated aggregation is found in the work area.
  • Do not clear or infill suspected breeding habitat while its status is being assessed.
  • Keep records of observations, photographs, dates, tides and the response taken.

Breeding habitat: Timing and protection measures

A reliable breeding season has not been established, so a simple seasonal exclusion period cannot be relied on. Apply avoidance and water-quality controls throughout the works period.

Use staged works where possible. Retain connected aquatic habitat and provide a clear route for animals to move away from temporary disturbance.

  • Avoid works in shallow mangrove and mudflat habitat where practicable.
  • Prevent isolation of pools and channels during tides and dewatering.
  • Use low-noise and low-vibration methods where works must occur in water.
  • Restore bed, bank and riparian habitat after construction.

Sheltering habitat: Resting areas

The Estuary Stingray rests on or beneath sandy and muddy estuary floors. It may bury itself beneath the sand, and mangrove roots and shallow sheltered waters are part of the broader habitat used by the species.

Stingrays can bury themselves beneath sand to rest and avoid predators. Bare substrate in quiet, shallow water is therefore a likely resting area, although no species-specific refuge site or seasonal roost has been defined.

Look for partially buried rays and shallow depressions on sand or mud. Give animals a clear path to deeper or connected water rather than herding them toward banks, machinery or isolated pools.

  • Check shallow flats, channel margins and sandy areas around temporary access points.
  • Keep plant, equipment and spoil out of likely resting areas.
  • Use a qualified aquatic fauna handler if a ray is trapped or must be moved under an approved procedure.

Sheltering habitat: Mangrove and bank features

Mangrove-lined rivers, mangrove roots, sheltered bays and tidal wetland margins provide cover and connected aquatic habitat. Bank trimming, mangrove removal, reclamation and shading changes can reduce the quality of these areas.

Retain natural banks, roots and low-flow channels wherever practicable. Do not assume that work above the waterline has no aquatic effect, as sediment and runoff can reach occupied habitat.

  • Delineate no-go areas around mangroves and wetland margins before mobilisation.
  • Clear only the minimum vegetation required for safe access.
  • Prevent stockpiles, spoil and wash water from entering tidal habitat.
  • Revegetate disturbed riparian areas with appropriate local species.

Sheltering habitat: Handling and incident response

The tail can cause injury, and unnecessary handling can harm the ray. Keep people clear, reduce disturbance and obtain specialist advice for any animal caught in a net, pond, trench, cofferdam or dewatering system.

Record the species, location, condition and release or rescue outcome. Report a suspected injury, death or repeated entrapment through the project fauna incident process and to the relevant authority where required.

  • Do not lift a ray by the tail or disc.
  • Do not leave an animal exposed on hot, dry ground.
  • Check sedimentation basins, pump intakes and isolated pools for aquatic fauna during dewatering.
  • Review the work method if repeated entrapment occurs.

Threats: Habitat loss and seabed disturbance

The main risks on development sites are loss of shallow estuarine habitat, altered water quality and restricted movement. As a near threatened species, the Estuary Stingray warrants precautionary planning, site checks and documented mitigation rather than relying on chance detection during works.

Reclamation, foreshore development, dredging, channel deepening and loss of mangroves have reduced or altered habitat in parts of the range. Disturbance to shallow muddy bays, bare sediment and tidal channels can remove feeding and resting areas.

Avoid aquatic habitat where practicable. Where avoidance is not possible, minimise the footprint, retain natural bed and banks, and restore temporary work areas to their original profile and habitat function.

  • Use the smallest practical clearing and dredging footprint.
  • Avoid unnecessary waterway crossings and permanent reclamation.
  • Prefer bridge or span solutions that maintain aquatic connectivity.
  • Map and protect connected habitat outside the immediate construction footprint.

Threats: Water quality, sediment and pollution

Turbidity, sedimentation, toxic runoff, acid sulfate soil discharges, industrial pollution, oil spills and agricultural chemicals can harm fish, prey and estuarine habitat. Poor water quality can also reduce spawning success and contribute to fish kills.

Prepare and maintain an erosion, sediment and pollution control plan. Include rainfall response, contaminated water containment, fuel storage, concrete washout and dewatering controls.

  • Keep clean water separate from dirty water.
  • Do not discharge turbid, acidic or contaminated water to connected waterways.
  • Inspect controls during and after rainfall.
  • Stop work and contain any spill or fish kill response area immediately.
  • Use gradual changes in noise and vibration where in-water works cannot be avoided.

Threats: Barriers, entrapment and altered flow

Causeways, floodgates, culverts, temporary dams, cofferdams and poorly designed crossings can restrict movement between marine, estuarine and freshwater habitat. Dewatering and sediment basins can trap rays and other aquatic fauna.

Design crossings to maintain fish passage and natural hydraulic function. During operation, inspect existing crossings for perched outlets, blockages and opportunities to improve passage.

  • Maintain low-flow channels and access between connected waterbodies.
  • Protect temporary instream structures from flood damage.
  • Check pumps, basins, trenches and isolated pools before and during dewatering.
  • Restore natural flow and bed profile when temporary works are removed.
  • Consider baffles, habitat restoration or other approved retrofits where existing culverts restrict passage.

Threats: Fishing, persecution and status response

The species is caught incidentally in some inshore prawn, tunnel net and recreational fisheries, and has been persecuted by some fishers and shellfish farmers. Habitat degradation and low resilience increase the consequence of local losses.

Queensland lists the Estuary Stingray as near threatened and includes it within the EVNT framework. Escalate records and incidents through the project ecologist, apply the relevant Queensland wildlife requirements, and obtain advice before disturbing suspected breeding habitat.

Queensland status: Near threatened and protected wildlife

Project implication: Tampering with a breeding place requires a species management program in Queensland

  • Brief all workers that rays must not be deliberately harmed or retained.
  • Use approved fauna handling and release procedures for any captured animal.
  • Prioritise avoidance for mangroves, shallow flats, tidal channels and connected estuarine habitat.
  • Increase survey and monitoring effort when works affect known habitat, repeated ray use or a suspected breeding place.
  • Document all records, mortalities, habitat disturbance and corrective actions.

Survey methodology: 1. Desktop assessment

The Estuary Stingray is poorly known and can be difficult to distinguish from similar rays. Survey design should focus on shallow estuaries, mangrove-lined rivers, tidal flats, bare substrates and lower river reaches, including areas that remain connected to the tide.

Map mangroves, tidal channels, mud and sand flats, seagrass, lower river reaches, estuary mouths and near-shore waters within and downstream of the work area.

Check museum records, local fisheries information, previous surveys, threatened species databases and records held by Traditional Owners or local land managers.

Treat records identified only as a generic stingray as unconfirmed until checked by a suitably experienced elasmobranch specialist.

Review the full tidal area that could be affected by noise, turbidity, sediment release, dredging, dewatering or changes to water movement.

Survey methodology: 2. Field detection

Use low disturbance methods first, such as visual searches from banks, bridges, vessels or elevated platforms during suitable tidal conditions.

Use baited remote underwater video where water clarity, depth and safety allow. Deploy cameras across mangrove edges, bare substrates, tidal channels, estuary mouths and other likely habitat.

Use drone imagery or aerial surveys to identify rays and feeding or resting pits in shallow, clear water. Avoid flights that could disturb animals or conflict with aviation, park or site requirements.

Use netting, trapping or capture surveys only under the relevant fisheries, wildlife and animal ethics approvals, with gear and handling supervised by an appropriately authorised person.

Survey methodology: 3. Timing and effort

Survey across the tidal cycle where practical, including periods when shallow flats and channels are accessible to rays. Record the tide, water depth, salinity, temperature, visibility and weather.

Repeat surveys when detection is likely to be reduced by turbidity, rainfall, high flow, vessel activity or strong wind. Use more than one survey method where the habitat is turbid or structurally complex.

No species specific breeding or migration season is established. Do not assume that a site is free of animals because a single survey finds none.

Scale survey effort to the footprint, duration and risk of the work. Increase effort where the project affects mangroves, tidal channels, shallow muddy or sandy habitat, or a known or suspected local population.

Survey methodology: 4. Records and identification

Record the date, time, location, tidal stage, coordinates, habitat, depth, salinity, water temperature, visibility, method and survey effort.

Record the number of animals, approximate disc width, behaviour, direction of movement, water depth and any signs of injury or capture.

Photograph animals only where this can be done safely and without handling or pursuing them. Include images of the dorsal surface, tail and any distinctive features needed for expert confirmation.

Submit uncertain records for review by a qualified ray taxonomist or the relevant state authority. Keep voucher photographs and survey data with the project environmental records.

Before habitat disturbance: 1. Approvals and permits

Avoidance is the preferred response for this near threatened species. The Estuary Stingray is an EVNT species in Queensland, where it is protected wildlife and interference with a breeding place requires a species management program.

Determine whether the action needs an EPBC Act referral. The Estuary Stingray is not listed under the EPBC Act in the cited action plan, but other listed matters or project impacts may still trigger referral requirements.

In Queensland, check the current EVNT requirements before clearing, dredging, bank works, dewatering or other activities that may affect the animal or its habitat. Obtain a species management program where works may tamper with a breeding place.

Obtain all relevant state permits and approvals for fauna survey, capture, handling, relocation, fisheries activities, dredging, waterway works and disturbance of protected wildlife. Confirm requirements separately for New South Wales, the Northern Territory and Queensland.

Use the most protective applicable approval condition where a project spans jurisdictions or affects connected estuarine habitat.

Before habitat disturbance: 2. Avoidance and site design

Avoid mangrove removal, tidal flats, bare sand or mud, tidal channels, estuary mouths and lower river habitat wherever practicable.

Keep crossings out of waterways where possible. Where a crossing is unavoidable, prefer a design that spans the waterway and retains the natural bed, banks, tidal exchange and fish passage.

Reduce the number of crossings, temporary instream structures, dredging areas, access tracks and work zones. Keep separate crossings as far apart as practical.

Design the work to prevent barriers to movement between marine, estuarine and freshwater areas. Protect water quality, sediment stability and natural tidal flows.

Before habitat disturbance: 3. Pre-clearance survey and exclusion

Complete a pre-clearance survey of all aquatic and intertidal habitat that may be affected, including areas downstream and within the likely zone of turbidity or altered flow.

Use an aquatic ecologist or authorised fauna professional to inspect work areas, temporary ponds, sediment basins, cofferdams, culverts and dewatering zones before they are isolated or disturbed.

Do not use a generic terrestrial fauna exclusion fence as a substitute for aquatic avoidance. Establish site-specific aquatic exclusion measures that maintain water movement and do not trap rays.

Set buffers around occupied habitat, feeding pits, resting areas or breeding places using advice from the project ecologist and the relevant authority. Do not apply an arbitrary fixed distance where tidal flow or water quality impacts extend beyond the visible work area.

Before habitat disturbance: 4. Timing and induction

No reliable breeding or migration period is established for this species. Schedule works for periods of low flow and low aquatic activity only where this reduces risk, and confirm the timing with the project ecologist and approval conditions.

Avoid starting works during conditions that increase turbidity, sediment movement, fish entrapment or loss of tidal connection.

Include the Estuary Stingray in the site environmental induction. Show workers how to recognise a ray, feeding pits and likely habitat.

Tell all workers that only authorised personnel may approach, capture, handle, release or relocate an animal. Give the fauna spotter catcher authority to stop work.

During habitat disturbance: 1. Sequential clearing and work controls

Use a slow, staged approach that keeps the animal in water and maintains an escape route. Stop work whenever an animal, possible breeding place or unexpected aquatic impact is identified.

Clear vegetation and disturb banks only where necessary and in small, sequential sections.

Complete aquatic works from the least disturbed area towards the remaining connected habitat, where the design allows animals to move away from the work front.

Maintain tidal exchange and fish passage during construction. Do not block channels, strand animals behind temporary barriers or allow water levels to fall rapidly during dewatering.

Install and maintain erosion and sediment controls before disturbance. Check them after rainfall, high flow and flood events.

During habitat disturbance: 2. Spotter catcher authority and animal handling

The fauna spotter catcher must have authority to stop machinery, dredging, pumping, piling, vehicle movement or other work that could injure an animal or damage occupied habitat.

Only authorised and suitably trained personnel may capture, handle, release or relocate an Estuary Stingray. Do not lift a ray by the tail, disc or sting.

Keep the animal in clean, well oxygenated water of suitable temperature and salinity while awaiting direction. Minimise air exposure, crowding, noise and handling.

Do not relocate an animal unless the approval, management plan and an appropriately qualified aquatic fauna specialist support that action. Prefer release into nearby suitable connected habitat over transport.

During habitat disturbance: 3. Active breeding places and occupied habitat

Stop work and establish a no-entry area if a possible breeding place, aggregation, resting area or repeated use area is found.

Do not disturb, fill, drain, isolate, cover or alter the water flow through the area until the project ecologist and relevant authority determine the response.

Because species specific breeding places are poorly understood, treat repeated sightings of adults or juveniles, concentrated use of shallow habitat and unusual ray activity as triggers for assessment.

Record the location, habitat, water conditions, number and behaviour of animals. Recommence work only after the required approval, species management program or written ecological direction is in place.

During habitat disturbance: 4. Injured or stranded animals

Stop the activity that caused or may worsen the incident and keep people and machinery away from the animal.

Contact the project ecologist, fauna rescue provider and relevant state wildlife or fisheries authority immediately. Follow the approved incident and animal welfare pathway.

Do not attempt to remove a barb, treat wounds, feed the animal or release it without specialist direction.

Record photographs, location, time, apparent cause, water conditions, actions taken and the animal's condition at handover.

During habitat disturbance: 5. Daily records

Record all sightings, captures, mortalities, injuries, relocations, work stoppages, inspections and water quality incidents.

Record the work activity, equipment, location, tidal stage, weather, turbidity controls and personnel involved.

Report any breach of an approval, species management program or exclusion measure to the site environmental manager immediately.

Keep records in a form that supports comparison between work stages and later monitoring.

After habitat disturbance: 1. Post-clearance checks

Post-clearance checks should confirm that no animals have been trapped and that tidal habitat remains connected. Use the results to adjust work methods and to meet approval and incident reporting requirements.

Inspect the full work area, temporary barriers, cofferdams, culverts, sediment basins, pumps and isolated pools after each work stage and before barriers are removed or water is returned.

Search for live or dead rays, stranded animals, feeding pits, damaged mangroves, blocked channels, unusual turbidity and areas of low oxygen.

Check downstream and adjacent habitat where sediment or contaminated water may have moved.

Have an aquatic ecologist confirm that water depth, flow, tidal exchange and fish passage are functioning as designed.

After habitat disturbance: 2. Relocated animals

Record the release location, date, time, method, animal condition, estimated size, habitat, salinity, water temperature and any identification marks.

Where approved, use photographs or other low stress methods to document survival and short term site use.

Do not assume that a released ray has survived. Report delayed mortality or repeated return to the work area to the project ecologist.

Review relocation outcomes before authorising further captures or changes to the work sequence.

After habitat disturbance: 3. Monitoring and reporting

Complete any post-work monitoring required by the approval, species management program, rehabilitation plan or environmental management plan.

Compare sightings, habitat condition, water quality and movement pathways with the pre-work baseline. Continue monitoring where habitat has been altered or a local population is suspected.

Report incidents, mortalities, injuries, unapproved disturbance and unexpected breeding or aggregation activity to the relevant authority within the required timeframe.

Submit significant records to the relevant state database or custodian so future assessments can improve the species' poorly known distribution.

After habitat disturbance: 4. Incident review

Hold a site review after any injury, mortality, stranding, major turbidity event, fish passage failure or unplanned habitat disturbance.

Identify the immediate and contributing causes, including plant movement, pump operation, sediment controls, lighting, noise, barriers and supervision.

Update the job hazard analysis, induction, sequencing, exclusion measures and emergency contacts before the next work stage.

Escalate repeated incidents to the project manager, approval holder and relevant authority.

Rehabilitation actions: 1. Restore aquatic habitat

Rehabilitation should restore the shallow, connected estuarine habitats used by the Estuary Stingray. The aim is to recover natural substrate, mangroves, tidal exchange, water quality and movement pathways rather than install structures designed for terrestrial breeding animals.

Reinstate the natural bed and bank profile, tidal channels and shallow flats after works.

Remove temporary barriers, hardstand, spoil, debris and redundant instream structures as soon as they are no longer needed.

Restore mangrove margins and other native riparian vegetation with locally suitable species. Protect new plantings from scour, grazing, weeds and flood damage until established.

Do not place rock, fill or other material over bare sand or mud habitat unless required by the approved design.

Rehabilitation actions: 2. Water quality and flow

Maintain natural tidal exchange and fish passage through rehabilitated crossings and channels.

Prevent sediment, acid sulfate soil runoff, hydrocarbons, concrete washout, pesticides and other contaminants from entering the waterway.

Use stable, low erosion surfaces and maintain erosion and sediment controls until the site is fully stabilised.

Monitor turbidity, salinity, dissolved oxygen and other project-specific water quality measures where works may affect estuarine habitat.

Rehabilitation actions: 3. Structures and shelter

Do not install nest boxes, bat boxes, artificial nests or roost structures for this species. These structures do not suit a demersal ray that uses aquatic substrates.

Do not create isolated pools, pits or barriers that could trap rays as tides fall or during maintenance.

Where habitat enhancement is needed, use locally appropriate aquatic features that retain safe water depth, natural substrate, tidal connection and fish passage. Obtain advice from an aquatic ecologist before installation.

Remove habitat features that cause stranding, scour, low oxygen conditions or entrapment.

Rehabilitation actions: 4. Weeds, lighting and disturbance

Control weeds without allowing herbicide, sediment or plant waste to enter the estuary.

Keep night lighting away from shallow water, mangrove edges and tidal channels where practicable. Use shielded, downward directed lights and the lowest effective intensity.

Limit vessel movement, piling noise, vibration and recreational access through rehabilitated habitat during establishment.

Prevent new access tracks, informal launch points and stockpiles from fragmenting mangroves or muddy and sandy tidal habitat.

Rehabilitation actions: 5. Long term monitoring

Monitor survival of mangrove plantings, bank stability, substrate condition, tidal exchange, water quality and fish passage at a frequency suited to the project risk.

Use repeat visual surveys, remote video, drone imagery or feeding-pit surveys where they can be conducted without disturbing animals.

Track Estuary Stingray sightings, habitat use, injuries, mortalities and any evidence of successful use of the restored area.

Continue monitoring until rehabilitation objectives are met and trends are stable. Review the design if rays remain absent, become stranded or show repeated avoidance of the restored habitat.

Sources