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Daintree Rainbowfish (Cairnsichthys bitaeniatus)

The Daintree rainbowfish is a small freshwater fish found only in the Wet Tropics of north eastern Queensland. It uses clear, shaded, permanently flowing rainforest streams and is highly vulnerable to changes in flow, water quality and stream habitat during clearing and construction. It is listed as Critically endangered under both the Commonwealth EPBC Act and Queensland legislation.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Queensland, Nature Conservation Act 1992: Critically endangered.

Breeding season

The Daintree rainbowfish is a resident freshwater fish of small, permanently flowing rainforest streams in the Daintree region. Some breeding may occur throughout the year, with likely peak spawning from August to November, before the wet season; this timing is inferred from related Wet Tropics rainbowfishes.

Breeding mode: Egg laying. Eggs are likely adhesive and attached to submerged vegetation or root masses, based on the closely related Cairns rainbowfish.

Clutch or litter size: Not recorded.

Incubation: Around 7 days, inferred from the Cairns rainbowfish.

Age at maturity: Likely before 1 year, inferred from the Cairns rainbowfish.

Breeding frequency: Some reproduction is likely to occur year round, with a probable peak from August to November.

Breeding sites: Likely submerged vegetation or root masses in permanently flowing streams. Confirmed Daintree rainbowfish breeding sites are not recorded.

Breeding timing may vary between streams and years with flow conditions, drought and the onset of the wet season.

  • Resident stream activity: The species is restricted to small, permanently flowing rainforest streams and should be treated as present year round where suitable habitat occurs.
  • Breeding and spawning: Breeding may occur year round, with likely peak spawning from August to November before the wet season.
  • Eggs and early young: Eggs and newly hatched young may be present throughout the year, with the greatest likelihood following the August to November spawning peak.
  • Targeted survey and habitat protection: Because the species is critically endangered, use targeted aquatic surveys across suitable permanent streams and protect flow, water quality, pools, submerged wood and streamside cover before clearing or construction.
  • Highest clearing risk: Avoid in-stream disturbance and habitat removal from August to November where practicable, and refer any proposed works in suitable habitat for specialist assessment and threatened species approvals.

Identification: Appearance and size

The Daintree rainbowfish is a moderate-sized, slender fish with a laterally compressed, rhombofusiform body. It can be confused with several other Wet Tropics rainbowfishes, so photographs and expert confirmation are recommended for unusual records.

Adults grow to around 66 mm standard length. The body is narrow and laterally compressed.

Useful distinguishing features include a flatter, straighter predorsal profile, a distinct yellow patch on the body, a short black stripe across the upper operculum and a prominent second dark stripe on the lower body.

Adult males usually have yellowish fins. Breeding males have yellow edging on the dorsal and anal fins.

Identification: Similar species

The closest potential confusion species is the Cairns rainbowfish, which was previously thought to include the northern population now recognised as the Daintree rainbowfish.

Other rainbowfishes that may occur in the broader region include the Eastern rainbowfish, Lake Eacham rainbowfish, Malanda rainbowfish and Utchee Creek rainbowfish.

  • Cairns rainbowfish, Cairnsichthys rhombosomoides.
  • Eastern rainbowfish, Melanotaenia splendida.
  • Lake Eacham rainbowfish, Melanotaenia eachamensis.
  • Malanda rainbowfish, Melanotaenia sp. nov. ‘Malanda’.
  • Utchee Creek rainbowfish, Melanotaenia utcheensis.

Identification: Calls and field signs

The species is not known to have a useful call for field detection. Echolocation is not relevant.

There are no distinctive nests, droppings, whitewash, odour or other terrestrial field signs to search for. Adults are most likely to be detected visually in clear pools and runs, or during targeted freshwater fish sampling.

  • Look for small fish near the surface to midwater in clear pools and higher-flow sections.
  • Pay particular attention to areas around large submerged wood.
  • Treat small rainbowfish records as uncertain until identified by a suitably experienced fish ecologist.

Identification: Handling records on site

Any suspected record should be photographed where practical and recorded with the exact waterway location, date, habitat description and disturbance context.

Avoid moving fish between waterways. Use clean equipment and follow the project’s aquatic fauna hygiene procedures.

Distribution: Australian range

The Daintree rainbowfish is endemic to Queensland and has an extremely restricted distribution in the Daintree region. It has no known range outside Australia.

The species is known from small tributaries of the Cooper Creek and Hutchinson Creek systems in the Daintree region of the Wet Tropics, north eastern Queensland.

The known inhabited area was reported as 12 km² of extent of occurrence and about 1200 m of stream length. Further surveys recorded the species in two additional tributaries.

  • State: Queensland only.
  • Region: Wet Tropics, Daintree area.
  • Catchments: Cooper Creek and Hutchinson Creek systems.

Distribution: What this means for project planning

A project near a permanent stream in the Daintree region should be treated as having potential habitat until a suitably designed aquatic fauna assessment shows otherwise.

The species may be missed if surveys are limited to large waterways or if they are conducted after flow has stopped. Check upstream and downstream habitats that could be affected by altered drainage, sediment or water extraction.

  • Map all permanent streams, tributaries, pools and flow paths within and downstream of the works area.
  • Review historical records and local knowledge before finalising clearing or construction controls.
  • Escalate any suspected record promptly because the known range is very small.

Habitat: Stream features

The Daintree rainbowfish is strongly associated with shaded, clear-water, permanently flowing lowland rainforest streams. Habitat can occur in both small shallow creeks and wider streams with deep pools.

Known habitat occurs at elevations of 20 to 40 m above sea level. Streams are generally shaded by lowland rainforest and have little or no aquatic vegetation.

One occupied creek was mostly shallow, with water less than 0.5 m deep, a wetted width of about 5 m and a sandy substrate. Other occupied creeks were about 10 m wide, generally deeper than 1 m, and included runs and pools up to 4 m deep.

  • Permanent baseflow.
  • Clear water and shaded banks.
  • Sand, cobble, runs and deeper pools.
  • High-flow areas and submerged wood.

Habitat: Features to check on a work site

Inspect permanent streams, small tributaries and connected pools, not only the main channel. Include areas that may receive runoff or altered drainage from the works.

Large submerged wood, deeper pools and shaded stream margins should be mapped before vegetation removal, access track construction, crossings or bank works.

  • Stream crossings and temporary waterway diversions.
  • Culvert inlets and outlets.
  • Sediment entry points and drainage lines.
  • Works near pools, submerged wood and high-flow runs.
  • Water extraction points and areas where flow may be reduced.

Habitat: Site assessment approach

Use a qualified aquatic ecologist to assess habitat condition and fish presence before works begin. Survey design should cover representative shallow sections, runs, pools and tributaries, with additional attention to permanent flow refuges.

Where the species may occur, plan works around maintaining stream continuity, natural flow and clear water. Confirm controls with the relevant Queensland environmental and fisheries authorities.

Foraging habitat: Feeding locations

The Daintree rainbowfish feeds in the water column and at the surface of flowing streams. Its feeding ecology is poorly known, but observations and comparison with the Cairns rainbowfish indicate reliance on aquatic and terrestrial invertebrate prey.

Fish have been observed feeding on terrestrial invertebrates at the water surface and on small prey carried in the current.

The species is usually found near the surface to midwater in deeper pools and areas of high flow.

  • Water surfaces beneath overhanging rainforest vegetation.
  • The upstream ends and margins of pools.
  • Runs and high-flow areas where prey is carried into the channel.
  • Areas around submerged wood.

Foraging habitat: Likely prey

The diet is expected to be similar to that of the Cairns rainbowfish. Reported comparison prey includes small benthic shrimp, aquatic Diptera, chironomid larvae, trichopteran larvae and ephemeropteran nymphs.

Foraging habitat: Construction risks to feeding habitat

Clearing overhanging vegetation can reduce terrestrial insect inputs and shade. Sediment, altered flow and loss of submerged wood can also reduce the quality of feeding areas.

Keep machinery, spoil and fuels away from the channel and flood-prone margins. Prevent turbid runoff from entering pools and runs.

  • Retain streamside shade where possible.
  • Keep natural flow paths connected.
  • Protect submerged wood unless removal is authorised and unavoidable.
  • Use effective sediment and erosion controls before earthworks start.

Breeding habitat: Likely spawning habitat

Breeding biology is not well documented for the Daintree rainbowfish. Comparisons with related Wet Tropics rainbowfishes suggest that spawning may occur through much of the year, with higher activity from August to November.

The species breeds in freshwater stream habitat. Related rainbowfish attach adhesive eggs to submerged vegetation and root masses, but this has not been confirmed specifically for the Daintree rainbowfish.

Potential spawning areas therefore include submerged roots, aquatic or marginal vegetation and sheltered structure in clear, permanently flowing sections.

  • Submerged root masses along shaded banks.
  • Vegetation or woody structure within the wetted channel.
  • Margins of pools and slow-flowing sections connected to permanent flow.

Breeding habitat: Breeding timing

Some reproduction may occur year-round. Peak spawning is inferred to occur from August to November, before the wet season.

The species is thought to be short-lived and highly fecund, but its confirmed maturity, egg numbers and early life stages are not established.

Likely peak spawning: August to November, based on comparison with related rainbowfish.

Related species lifespan: The Cairns rainbowfish comparison is 2 to 3 years.

Breeding habitat: Controls near potential breeding areas

Avoid disturbing submerged roots, marginal vegetation and woody structure in permanent streams. Do not isolate pools or leave fish stranded during temporary waterway works.

Where works cannot avoid occupied or potential breeding habitat, obtain project-specific advice from a qualified aquatic ecologist and the relevant regulator before disturbance.

  • Schedule in-channel works to minimise the period of habitat disturbance.
  • Maintain water depth, flow and fish passage through temporary works.
  • Use fish rescue or relocation only under an approved, species-appropriate procedure.
  • Inspect isolated pools and dewatered sections for fish before refilling, draining or backfilling.

Sheltering habitat: Refuge features

The Daintree rainbowfish uses deeper pools, high-flow areas and large submerged wood within shaded rainforest streams. These features should be treated as aquatic refuge habitat during site planning and construction.

The species is usually seen near the surface to midwater in deeper pools. Occupied streams include runs, pools and large submerged wood.

Shaded banks and connected permanent flow are likely to help maintain suitable temperature, cover and water quality.

  • Pools deeper than adjacent shallow stream sections.
  • Large submerged wood.
  • High-flow runs connected to pools.
  • Shaded rainforest margins and overhanging vegetation.

Sheltering habitat: Protection during works

Keep refuge pools connected to flowing water. Avoid placing temporary crossings, pumps, spoil or sediment barriers in pools or around submerged wood.

If a stream must be isolated or dewatered, stop work and use a qualified aquatic fauna team to assess and manage fish before the habitat is disturbed.

  • Maintain upstream and downstream fish passage.
  • Prevent sudden drops in water level.
  • Keep pumped discharge free of sediment and contaminants.
  • Retain shade and stable stream banks wherever practicable.

Threats: Flow reduction and water extraction

The Daintree rainbowfish is Critically endangered and has a very small range. Even short-term changes to flow, water quality or stream structure can affect a local subpopulation, so development controls should be conservative.

Loss of stream flow is a major threat. Drought, climate change and water extraction can reduce or remove suitable habitat, especially in small tributaries.

Construction water take, diversion, pumping and altered drainage can reduce flow or strand fish in isolated pools.

  • Obtain the required approvals before taking or diverting water.
  • Maintain natural inflows and downstream flows.
  • Monitor water levels and flow during works near permanent streams.
  • Stop or modify works if fish become stranded or flow is interrupted.

Threats: Sediment, pollution and water quality

Earthworks, bank disturbance and poorly managed runoff can cloud clear streams, smother habitat and affect aquatic invertebrate prey. Fuels, concrete washout and other contaminants can cause acute harm in small waterways.

Install and maintain erosion and sediment controls before clearing or soil disturbance. Keep clean water separate from work areas.

  • Protect stream banks and riparian vegetation.
  • Use staged clearing and stabilise exposed soil promptly.
  • Keep stockpiles, fuels and chemicals outside drainage paths.
  • Inspect controls after rainfall and repair failures immediately.

Threats: Loss of shade, wood and channel structure

Removing rainforest vegetation can increase water temperature and reduce terrestrial prey. Removing submerged wood or reshaping pools and runs can remove shelter and feeding habitat.

Avoid unnecessary clearing beside permanent streams and retain natural channel features.

  • Minimise the clearing footprint at stream crossings.
  • Retain overhanging vegetation and root structures where safe.
  • Do not remove submerged wood unless it is necessary for safety or approved works.
  • Restore disturbed banks with appropriate native Wet Tropics vegetation.

Threats: Catastrophic events and cumulative impacts

The species is confined to a small area, so a severe fire, drought, flood, pollution event or other catchment-scale disturbance could affect a large proportion of the remaining population.

Treat every known or potential site as part of a connected catchment. Record observations and report suspected impacts promptly.

  • Prepare spill, flood and emergency dewatering procedures before works start.
  • Use aquatic fauna incident reporting for fish deaths, stranding or major turbidity events.
  • Coordinate controls across the full drainage line, including upstream and downstream areas.
  • Seek specialist advice before any translocation, captive holding or release.

Survey methodology: 1. Desktop assessment

The Daintree rainbowfish is a small, critically endangered freshwater fish with a very restricted range. Surveys should focus on clear, permanently flowing rainforest streams and use more than one detection method, because water level, flow and turbidity can affect detectability.

Map all permanent and intermittently affected stream reaches within and downstream of the work area. Give particular attention to lowland rainforest streams at 20 to 40 m elevation, including shallow reaches, runs, pools and areas around submerged wood.

Check whether the site connects to the Cooper Creek or Hutchinson Creek systems and whether it could affect the three known subpopulation areas or the additional tributaries where the species has been recorded.

Review proposed changes to stream flow, water extraction, crossings, sediment discharge, clearing, drainage and lighting before field work begins.

Known distribution: Three small subpopulations occur in tributaries of the Cooper Creek and Hutchinson Creek systems in the Daintree region, with further records from two additional tributaries.

Known occupied area: About 12 km² of extent of occurrence and about 1200 m of stream length were reported.

  • Obtain current threatened species records and habitat mapping from the relevant Queensland authority.
  • Treat apparently suitable habitat as potentially occupied where records are old, imprecise or absent.
  • Engage a suitably experienced freshwater fish ecologist when identification from similar rainbowfishes may be difficult.

Survey methodology: 2. Stream and fish surveys

Survey the full range of suitable aquatic habitat, including pools, runs, shallow margins and areas beside large submerged wood. Look for fish near the surface to midwater in deeper pools and high-flow areas.

Use a combination of visual observation, hand nets and seine nets where safe and permitted. Electrofishing may be used only by trained operators under the required animal ethics, wildlife and project approvals.

Use non-destructive methods first. Avoid methods that could injure fish, disturb spawning habitat or spread aquatic pathogens between catchments.

Habitat features to target: Permanently flowing, shaded, clear-water rainforest streams with pools, runs, sand or cobble beds and submerged wood.

  • Sample upstream and downstream of the proposed disturbance, and include an unaffected comparison reach where practical.
  • Use several survey visits rather than relying on one negative result.
  • Survey during daylight when water is clear enough for observation and netting, and record conditions that could reduce detection.
  • Do not survey during unsafe flows. Reassess after water levels and visibility return to suitable conditions.

Survey methodology: 3. Timing and survey conditions

Breeding biology is poorly known. Reproduction may occur throughout the year, with likely peak spawning from August to November based on related Wet Tropics rainbowfish. There is no known migration period that provides a clear survey window or a safe period for disturbance.

Plan surveys before the peak spawning period where practicable, then repeat them during or after that period if the project could affect aquatic habitat. Avoid surveys during high turbidity, extreme flows or conditions that could damage eggs or larvae.

Record the date, time, recent rainfall, water level, flow, visibility and turbidity for every visit.

Likely breeding period: Some reproduction may occur year-round, with peak spawning likely from August to November.

  • Record whether the stream is flowing continuously and whether pools, runs, shallow margins and submerged wood are present.
  • Record the length and location of each reach surveyed using a map or GPS.
  • Record all captured, observed or photographed fish and any uncertain identifications.
  • Photograph diagnostic features where handling is authorised, especially the yellow body patch and yellow fin edging of breeding males.
  • Record negative survey results as well as detections, with the area and conditions covered.

Survey methodology: 4. Identification and handling

Distinguish the Daintree rainbowfish from the Cairns rainbowfish and other Wet Tropics rainbowfishes before making a clearance decision. Identification can be difficult because the species was only formally described in 2018 and has subtle similarities to related fish.

Use photographs, field measurements and expert confirmation where identification is uncertain. Keep handling time short and maintain fish in clean, well-oxygenated water at the capture site unless an approved relocation plan applies.

  • Do not move fish between catchments or release them outside the approved receiving area.
  • Use clean equipment between sites to reduce disease and pest transfer.
  • Record the number of fish, life stage if known, location, habitat, method and fate of every handled individual.
  • Report suspected Daintree rainbowfish detections promptly to the project ecologist and relevant Queensland authority.

Before habitat disturbance: 1. Approvals and permits

Avoidance is the preferred control for this species. Because it is listed as critically endangered nationally and in Queensland, confirm the approval pathway before any work that may affect occupied stream habitat, flow, water quality or a breeding place.

Have the proponent’s environmental approvals reviewed by the project ecologist before design is finalised. A project that may have a significant impact on the Daintree rainbowfish may require referral or approval under the Environment Protection and Biodiversity Conservation Act 1999.

Confirm the Queensland requirements under the Nature Conservation Act 1992 and the Nature Conservation (Animals) Regulation 2020. The species is listed as critically endangered in Queensland.

Obtain any Queensland wildlife permits required for survey, capture, handling, relocation, salvage or scientific use. Do not rely on a general fauna spotter catcher authorisation unless it expressly covers this species and activity.

Where works may tamper with a breeding place, confirm whether a Queensland species management program is required and ensure all conditions are included in the work method.

Conservation status: Critically endangered under the EPBC Act and critically endangered in Queensland.

  • Keep copies of approvals, permit conditions, maps and the approved aquatic fauna management plan at the work front.
  • Nominate the person responsible for stopping work and contacting the regulator.
  • Do not begin clearing, dewatering, diversion or discharge until the approval conditions have been briefed to the crew.

Before habitat disturbance: 2. Avoidance and site design

Keep the stream, banks, pools, submerged wood and connected wet areas outside the construction footprint wherever possible. Avoid changing permanent flow, reducing pool depth, removing large submerged wood or increasing sediment and nutrient input.

Retain shaded rainforest cover over the channel and riparian zone. Design crossings and access routes to minimise in-stream entry, bank disturbance and the length of any temporary works.

Do not use a generic fauna buffer as a substitute for a site-specific aquatic habitat assessment. Set the no-go area from the habitat that must be retained and the conditions of the relevant approval.

  • Locate stockpiles, refuelling areas, wash-down areas and spoil away from the stream and drainage lines.
  • Maintain downstream flow during works and provide a stable bypass only where approved by the project ecologist and regulator.
  • Use sediment and erosion controls before ground disturbance starts.
  • Prevent concrete, hydrocarbons, chemicals, chlorinated water and turbid water from entering the stream.
  • Protect pools, runs, shallow margins, root masses and submerged wood from plant access.

Before habitat disturbance: 3. Pre-clearance survey and work planning

Complete the aquatic pre-clearance survey shortly before disturbance, after the final design and before vegetation, bank or bed disturbance. Survey all areas that may be dewatered, isolated, crossed or exposed to sediment.

Confirm whether the work area contains suitable habitat even if fish are not detected. A negative result does not remove the need for controls because the known range is small and detection varies with conditions.

Prepare a staged aquatic fauna management plan that covers capture, temporary holding, relocation, dewatering, water quality, rescue and incident response.

  • Mark the approved work area and aquatic exclusion zones on the ground and on construction plans.
  • Identify upstream and downstream refuge areas that are not affected by works.
  • Schedule high-risk in-stream works outside August to November where practicable, while recognising that breeding may occur throughout the year.
  • Allow time for repeat surveys, permit conditions and regulator notification before the start date.
  • Use a weather and flow trigger that postpones work when heavy rain, flooding or severe turbidity prevents safe fish rescue.

Before habitat disturbance: 4. Crew induction and exclusion

Give every worker a short site induction before entering the work area. Explain the species’ appearance, habitat, legal protection, no-go areas and the stop-work process.

Only authorised and suitably trained people may capture, handle, transport or release fish. All other workers must leave aquatic fauna undisturbed and report sightings immediately.

  • Display a photograph and identification summary at the site office and work front.
  • Mark aquatic exclusion zones with visible signs and barriers.
  • Keep plant, vehicles, materials and people out of the stream unless the approved method allows access.
  • Provide clean, disinfected nets, buckets and footwear for aquatic fauna work.
  • Nominate a fauna spotter catcher with authority to stop work without seeking supervisor approval.

During habitat disturbance: 1. Sequential clearing and aquatic protection

Use a slow, staged approach and keep the stream flowing wherever possible. The fauna spotter catcher must have clear authority to stop work when fish, eggs, a suspected breeding place or an unexpected change in water quality is found.

Clear from the least sensitive area towards the retained habitat. Complete terrestrial clearing and sediment controls before entering the aquatic work zone.

Isolate only the smallest area needed for the task, and only under the approved method. Check isolated water for fish before pumping or draining.

Keep pumps screened and set above the bed. Prevent fish, eggs, sediment and debris from being drawn into pumps or discharged downstream.

  • Inspect the work area before each shift and after rainfall or changes in flow.
  • Maintain downstream passage and avoid trapping fish against barriers.
  • Remove temporary barriers progressively and check both sides before opening the area.
  • Keep plant out of pools and away from submerged wood unless removal is specifically approved.
  • Stop work if water becomes visibly turbid, flow is interrupted, fish are stranded or a control fails.

During habitat disturbance: 2. Capture, handling and relocation

Capture fish only under the approved permit and relocation method. Use the least stressful technique available, keep fish in clean, shaded, oxygenated water and minimise handling time.

Release relocated fish only at the approved receiving site within the same connected system, unless an approval expressly authorises another arrangement. Do not transfer fish between catchments.

The receiving site must have suitable flowing water, adequate depth and cover, and must not be affected by the same works or water quality incident.

  • Record the capture location, time, method, number of fish, condition, holding time and release location.
  • Use separate clean equipment for each site or disinfect it between sites.
  • Do not retain fish for identification, photography or transport unless the relevant authorisation allows it.
  • Release fish promptly when the site is safe and conditions are suitable.
  • Report mortalities, unusual behaviour or repeated failed captures to the project ecologist.

During habitat disturbance: 3. Unexpected breeding places or concentrations

Stop work immediately if fish are concentrated in a pool, eggs are suspected, or a breeding place is found in or beside the work area. Protect the location from people, plant, pumps, sediment and changes in flow.

The species’ breeding place is not well defined. Related rainbowfish may attach eggs to submerged vegetation or root masses, so treat submerged vegetation, root masses and sheltered stream margins as potentially sensitive.

The fauna spotter catcher must contact the project ecologist and follow the approval and species management program before work resumes.

  • Set a visible exclusion zone around the location without entering the water unnecessarily.
  • Do not remove vegetation, roots, wood or substrate from the area.
  • Do not relocate eggs, larvae or adults unless the approved method specifically allows it.
  • Record photographs, location, habitat, water conditions and the action taken.
  • Notify the relevant authority where required by the approval, permit or species management program.

During habitat disturbance: 4. Injured or dead animals

Stop nearby work and keep people and plant clear of an injured Daintree rainbowfish. Do not return an injured fish to the stream without advice from the authorised aquatic fauna handler or a qualified aquatic veterinarian.

Use the project’s approved wildlife care pathway. The pathway should identify the permitted carer, aquatic veterinarian, transport method, holding facility and notification requirements before work begins.

  • Record the location, apparent cause, condition and photographs where this can be done without further harm.
  • Keep the fish in suitable clean water and shade only if directed by the authorised handler.
  • Do not euthanise, preserve or dispose of the animal without professional advice and approval.
  • Treat any fish kill, spill, dewatering event or sediment release as an environmental incident and escalate immediately.

During habitat disturbance: 5. Daily records and stop-work control

Maintain a daily aquatic fauna record for every work shift. The record should support permit reporting and allow the team to identify repeated risks or areas where controls are failing.

The fauna spotter catcher should have direct communication with the supervisor and plant operators, and should record every stop-work direction and restart decision.

  • Record weather, rainfall, flow, turbidity, work area, equipment, survey effort, captures, relocations, injuries, mortalities and incidents.
  • Record the names and authorisations of people who handled fish.
  • Log all changes to the approved method and the person who authorised them.
  • Do not restart until the fauna spotter catcher and project ecologist agree that the approved controls are in place.

After habitat disturbance: 1. Immediate post-clearance checks

Post-clearance checks confirm that fish have not been stranded and that the stream remains connected, flowing and free of harmful discharges. Continue checks after construction because delayed sediment, flow and lighting effects can affect this species.

Inspect the entire disturbed reach after plant leaves and again after the first substantial rainfall or flow change. Check pools, shallow margins, isolated depressions, pump intakes, sediment controls and downstream areas.

Look for stranded fish, dead fish, damaged submerged wood, blocked flow, sediment plumes, bank collapse and loss of riparian shade.

  • Remove temporary barriers, hoses and equipment that could trap fish as soon as the approved work allows.
  • Confirm that water is flowing through the channel and that downstream passage is open.
  • Check that no fish remain in dewatered areas before backfilling, grading or removing isolation structures.
  • Escalate any mortality, fish distress or water quality breach immediately.

After habitat disturbance: 2. Monitoring and compliance reporting

Monitor the retained and rehabilitated stream reaches using the same methods and locations used for the pre-work assessment where practical. Compare fish detections, habitat condition, flow and water clarity over time.

Set monitoring duration and frequency through the approval, species management program and project risk assessment. Increase monitoring after major rainfall, spills, dewatering or unexpected fish observations.

  • Record fish observations, survey conditions, habitat, water quality observations, weed cover, bank stability and riparian condition.
  • Map any change to pools, runs, submerged wood, root masses or shaded cover.
  • Submit required records and incident reports within the timeframes set by approvals and permits.
  • Retain photographs, GPS data, field sheets and laboratory or expert identification records in the project file.

After habitat disturbance: 3. Relocated animals and release sites

Check approved release sites after relocation to confirm that flow, depth, cover and water quality remain suitable. Do not disturb relocated fish unnecessarily.

If fish are repeatedly found outside the approved receiving area, or are missing from a release site, notify the project ecologist and review the relocation method.

  • Record the number and condition of fish released at each site.
  • Inspect for dead or distressed fish where this can be done safely and without further disturbance.
  • Do not supplement or restock a site unless this is authorised under an approved recovery or translocation program.
  • Use the monitoring results to adjust barriers, sediment controls, flow management and rehabilitation.

After habitat disturbance: 4. Incident review and corrective action

Review every stop-work event, fish injury, mortality, spill, turbidity event and flow interruption. Include the fauna spotter catcher, construction supervisor and project ecologist in the review.

Focus on what failed, how quickly it was detected, whether approval conditions were met and what must change before similar work continues.

  • Update the work method, induction and risk assessment after each significant incident.
  • Repair failed erosion, sediment, flow or exclusion controls before restarting work.
  • Notify regulators and approval holders where required.
  • Use lessons from the review to refine future survey timing, site design and aquatic fauna procedures.

Rehabilitation actions: 1. Restore stream form and flow

Rehabilitation should restore a shaded, permanently flowing rainforest stream with stable banks, clean water, natural pools and runs, and submerged cover. The Daintree rainbowfish is a fish, so nest boxes, bat boxes and terrestrial artificial roost structures are not suitable replacement breeding structures.

Reinstate natural drainage and continuous flow as soon as practicable. Match the original channel form where this can be done without creating new erosion or flood risk.

Restore a mix of shallow areas, runs and deeper pools. Retain or replace natural submerged wood only where approved and where it will remain stable during flow events.

Do not create isolated ponds or artificial barriers that prevent movement between connected stream habitats.

  • Remove temporary crossings, bunds, pipes and diversion structures when no longer needed.
  • Stabilise banks with locally appropriate native vegetation and natural materials.
  • Keep bare soil, spoil and construction materials out of the channel.
  • Use clean local materials where substrate replacement is approved.
  • Protect restored areas from plant, vehicles, livestock and repeated trampling until stable.

Rehabilitation actions: 2. Restore shade, roots and breeding habitat

Re-establish rainforest canopy and riparian vegetation along disturbed banks and stream margins. Shading helps maintain suitable water conditions and supports the aquatic invertebrates that rainbowfish are expected to eat.

Related rainbowfish may attach eggs to submerged vegetation and root masses. Restore natural vegetation, root masses and stable submerged margins rather than installing generic artificial breeding structures.

Do not place nest boxes, bat boxes, artificial nest sites or roost structures in the stream. These structures are not relevant to the breeding biology of this fish.

  • Plant locally appropriate native rainforest species suited to wet stream margins.
  • Protect naturally regenerating seedlings and retained root systems.
  • Keep chemical fertilisers, herbicides and mulch out of the channel unless their use is specifically approved and controlled.
  • Use erosion control that does not smother pools, roots or submerged wood.
  • Monitor whether restored vegetation survives through dry periods and high flows.

Rehabilitation actions: 3. Control weeds and water quality risks

Remove environmental weeds from the riparian zone using methods that prevent herbicide, soil and plant material entering the stream. Prioritise weeds that shade out native regeneration, destabilise banks or obstruct flow.

Maintain sediment, nutrient and contaminant controls until ground cover and bank stability are established.

Prevent polluted runoff from roads, compounds, stockpiles and disturbed slopes entering the stream.

  • Use clean soil, rock, mulch and plant material that is free of declared weeds and aquatic pests.
  • Inspect erosion and sediment controls after rain and repair them promptly.
  • Keep fuels, oils, concrete washout and chemicals outside drainage pathways.
  • Treat weed infestations progressively and avoid large-scale simultaneous bank disturbance.
  • Record weed species, treatment areas and follow-up results.

Rehabilitation actions: 4. Lighting, access and long-term protection

Keep artificial lighting away from the stream and riparian corridor. Where lighting is necessary for safety, direct it only to the work area and avoid shining across pools or along the channel.

Prevent new access tracks, fencing, drains and utilities from fragmenting stream habitat or altering flow. Maintain a vegetated buffer appropriate to the site risk and approval conditions rather than relying on a standard distance.

  • Use the lowest practical light intensity and switch lights off when not required.
  • Shield lights and aim them away from water.
  • Keep vehicles and machinery out of restored stream margins.
  • Control unauthorised access to pools, banks and rehabilitation areas.
  • Include the restored reach in the site environmental management plan and handover documentation.

Rehabilitation actions: 5. Long-term monitoring and adaptive management

Continue monitoring until flow, banks, vegetation, water quality and aquatic habitat are stable and the project’s approval conditions are met. The species is poorly known, so monitoring should be able to detect unexpected effects and guide corrective action.

Use repeat fish surveys, habitat assessments and photographic points at the disturbed reach and a suitable comparison reach where practical.

  • Track fish detections, life stages where identifiable, habitat use, pool condition, submerged cover, shade and riparian regeneration.
  • Review results after dry periods, major floods, fires or other events that may affect the small known range.
  • Repair erosion, replace failed plantings and remove new weeds promptly.
  • Escalate declining habitat condition or repeated fish mortality to the project ecologist and relevant authority.
  • Keep monitoring records with the project’s threatened species compliance file.

Sources