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Southern Purple-spotted Gudgeon (Mogurnda adspersa)

The southern purple-spotted gudgeon is a small, non-migratory freshwater fish of slow-flowing or still waters, including wetlands, billabongs, backwaters, creeks and weedy pools. It is listed as Endangered under the EPBC Act and is highly sensitive to loss of aquatic vegetation, altered water levels, sedimentation, poor water quality and introduced fish, so construction near wetlands and waterways requires careful habitat protection.

Conservation status

Commonwealth, EPBC Act 1999: Endangered.

Victoria, Flora and Fauna Guarantee Act 1988: Critically endangered.

Breeding season

The documents describe breeding from spring into summer, with regional differences in the reported season. The species is non-migratory, but local movement between connected pools, wetlands and backwaters is possible habitat-wise and should not be assumed to occur over long distances.

Month values are ordered January to December. Seasonal timing varies between regions, and water temperature and inundation appear to influence spawning.

  • Breeding: South Australian information places breeding in spring when water exceeds 20°C. NSW and Victorian information describes spawning in summer, also above 20°C. The combined period is approximately October to February, with the strongest evidence for warmer months.
  • Young: Eggs hatch after about 3 to 9 days. The male guards and fans the eggs, and early recruitment occurs in vegetated, low-flow habitat with suitable spawning surfaces. The documents do not define the full period of parental dependence.
  • Highest clearing risk: Clearing or disturbance is most likely to harm the species from approximately October to February, when spawning, egg guarding, hatching and early recruitment may occur. Habitat loss or dewatering can also harm adults at any time, especially in permanent refuge pools.

Identification

This is a small, robust gudgeon with a rounded head, small mouth and rounded tail. It is demersal and cryptic, and may be difficult to detect because it often remains close to cover on the bottom of slow or still water.

Adults are generally dark brown or chocolate on the back, fading to pale brown, fawn, cream or yellowish brown on the belly. The body has white and red spots, dark patches and a blue to bluish-purple wash on the flanks, which becomes brighter during breeding. The fins are yellow, darkening towards the edges, and the dorsal and anal fins may have yellow marginal bars.

Body form: Rounded head, relatively small mouth, rounded tail and two dorsal fins, with the first shorter and lower than the second.

Typical length: 6 to 12 cm in South Australia; around 15 cm maximum reported in NSW.

Identification: Separating it from similar gudgeons

In NSW, three red-maroon bars on the cheek help distinguish this species from similarly shaped Cox's gudgeon, striped gudgeon and flathead gudgeon, including at small sizes. The blue wash on the flanks and the combination of red and white spots are also useful features, although colours brighten during breeding and may vary with condition and light.

Identification: Field signs and handling

There are no documented tracks, scats, calls, nests, sloughs or other terrestrial field signs for this fish. A live fish, a photograph or a confirmed capture is the relevant field evidence, but the species is demersal, cryptic and difficult to catch. Do not remove native fish from the water or retain wild-caught individuals without the required approval.

  • Treat an unidentified small gudgeon from suitable habitat as potentially significant until it has been identified by a suitably experienced person.
  • Record the waterbody, location, date, habitat, photographs and any capture details, and follow the relevant state reporting and permit requirements.
  • Avoid moving, handling or relocating fish unless this forms part of an approved survey, rescue or recovery program.

Distribution: State and catchment range

The species occurs in eastern and southern Australia, with distinct eastern and western populations documented in NSW and remnant or reintroduced populations in the Murray-Darling Basin. Records and status differ between states, and the available documents do not provide a complete national bioregional range or a current Queensland distribution.

In NSW, an eastern population is recorded from coastal catchments north of the Clarence River, with extant populations reported in the Richmond catchment and Hunter Valley. A western population occurs in the Murray-Darling Basin, with remnant populations in the Macquarie, Gwydir and Border Rivers catchments and a self-sustaining captive-bred population in the Castlereagh Catchment.

In Victoria, historical records include Benalla, near Bendigo, Dinner Creek near Stawell and Wangaratta. The species was considered regionally extinct after the Cardross Lakes population died out, but two fish were found at Third Reedy Lake near Kerang in October 2019. In South Australia, it was historically widespread and common in patches throughout the Lower Murray, but is now rarely found in the wild.

Distribution: Subpopulations and trend

The western NSW populations are small, isolated and disconnected, with limited gene flow. The eastern NSW population has few recent records, despite targeted sampling. In Victoria, the known population is concentrated at one site and remains at high risk of returning to regional extinction without an active recovery program.

South Australian fish were rescued from a drying River Murray wetland in 2007 after rediscovery in 2004. Captive breeding and releases have been used at Piawalla Wetland near Murray Bridge and in surrogate wetlands and farm dams.

Victorian extent of occurrence: Estimated at 4 km².

Victorian area of occupancy: Estimated at 4 km².

Victorian known locations: One location, centred on the Third Reedy Lake population.

Estimated mature individuals in Victoria: 8 to 40 individuals in the 2021 assessment.

Victorian population trend: Projected to continue declining without successful active recovery.

Distribution: Bioregional context

The documents identify the Lower Murray and the Murray-Darling Basin as the main southern inland areas relevant to this species. They do not provide a complete list of Australian bioregions or enough information to assign every record to a formal IBRA bioregion.

Habitat: Waterbodies and flow

Southern purple-spotted gudgeons use permanent or semi-permanent freshwater with slow flow, low turbidity and substantial cover. They are most often associated with vegetated margins, backwaters, billabongs, wetlands and small to medium streams rather than fast-flowing exposed channels.

Documented habitats include slow-flowing streams, small streams, rivers, creeks, billabongs, backwaters beside rivers, wetlands, dune lake systems and slow-flowing weedy pools. In the Lower Murray, the species is associated with still or low-flowing water over mud, coarse sand or gravel.

  • Protect permanent pools, wetland depressions, backwaters and low-flow channels connected to or adjacent to occupied waterways.
  • Maintain water levels and seasonal inundation patterns that support aquatic vegetation, spawning substrates and recruitment.

Habitat: Cover and substrate

Dense submerged plants, emergent reeds, overhanging bank vegetation, undercut banks, leaf litter, rocks, timber debris and snags provide cover. Aquatic plants are used for living, feeding and breeding, while firm rocks, timber and broad-leaved plants provide egg-laying surfaces.

  • Retain aquatic plants, emergent reeds, overhanging vegetation, snags, rocks and undercut banks within and beside waterways.
  • Prevent sediment entering occupied or suitable habitat, because increased turbidity and siltation can reduce habitat quality and smother eggs.

Habitat: Physical limits

The documents do not provide an elevation limit or a defined climatic envelope. They do show that breeding is associated with water temperatures above 20°C and that populations occur in both coastal catchments and inland Murray-Darling Basin wetlands and streams.

Breeding water temperature: Above 20°C.

Typical water condition: Still or slow-moving water with low turbidity.

Foraging habitat: Diet

This benthic fish waits near the bottom and ambushes prey that comes within reach. It feeds in vegetated, sheltered parts of wetlands, streams, billabongs and backwaters.

The diet includes aquatic macroinvertebrates such as insect larvae, terrestrial insects and their larvae, worms, glass shrimp, small fish, tadpoles and small yabbies. Some plant matter is also eaten.

Feeding type: Carnivorous, with some plant matter recorded in the diet.

Main prey: Insects and larvae, worms, small fish, tadpoles, glass shrimp and small yabbies.

Foraging habitat: Foraging places and method

The species spends much of its time lying on the bottom and ambushing prey. Suitable foraging areas include dense aquatic vegetation, low-flow wetland margins, backwaters, sheltered stream edges and areas with leaf litter, rocks, snags or overhanging vegetation.

Foraging range: No home-range or movement distance is reported in the documents.

  • Retain structural cover and aquatic plants during waterway and wetland works.
  • Use erosion and sediment controls to maintain clear water and protect benthic prey habitat.
  • Avoid draining or isolating low-flow pools that provide feeding habitat.

Breeding habitat: Breeding biology

Breeding occurs in warm water, with eggs attached to firm surfaces or broad-leaved plants. The male guards and fans the eggs until they hatch, so loss of spawning surfaces, aquatic vegetation or suitable water levels can affect recruitment.

Males perform an elaborate courtship display. Females may lay several batches in a season, and the eggs are deposited in clusters on rocks, wood, logs or broad-leaved aquatic plants. The male guards and fans the eggs, preventing sediment from accumulating over them.

Breeding season: Spring in South Australia and summer in NSW and Victoria, when water temperatures are above 20°C.

Egg batches: Females may lay several batches per season; the Victorian assessment describes 7 to 10 successive broods in one season.

Egg number: 30 to 1,300 eggs per batch in NSW; 284 to 1,300 in the Murray-Darling Basin source cited by the Victorian assessment.

Egg size: About 2 to 4 mm long, elongated, sticky and transparent.

Incubation: About 3 to 9 days, depending on water temperature.

Age or size at maturity: Males mature at about 4.5 cm and females at about 5 cm; an age at maturity is not reported.

Lifespan: Possibly up to 9 years.

Breeding habitat: Breeding habitat features

Spawning habitat includes aquatic vegetation, rocks, timber debris, logs and other firm surfaces in still or slow-flowing water. Recruitment also depends on suitable water levels and inundation of wetland habitat. Turbidity and sediment can smother eggs, while carp can disturb sediment and damage spawning habitat.

  • Retain broad-leaved aquatic plants, rocks, timber debris and logs in suitable breeding habitat.
  • Prevent sediment release during clearing, bank works, excavation, dredging and construction near occupied or potential habitat.
  • Maintain water levels and seasonal inundation that allow spawning sites to remain wet through egg development and early recruitment.

Sheltering habitat: Aquatic cover

The species shelters close to the bottom among dense aquatic plants and physical cover. It does not use dens, hollows, burrows or roosts, and no shelter dimensions are reported.

Important cover includes submerged plants such as water ribbon and foxtail, emergent reeds such as club rushes, overhanging grasses, undercut banks, leaf litter, rocks, snags and timber debris. Fish are commonly collected close to cover over mud, sand, gravel or coarse sand.

Shelter type: Aquatic vegetation, bank vegetation, undercut banks, leaf litter, rocks, snags and timber debris.

Shelter dimensions: No dimensions are reported.

  • Do not clear aquatic or edge vegetation unless authorised and assessed for threatened fish impacts.
  • Retain snags, rocks, timber debris, leaf litter and undercut banks where they do not create an unavoidable safety or flood risk.
  • Keep machinery, spoil, fuels and concrete washout away from the wetted channel and vegetated margins.

Sheltering habitat: Drought and refuge sites

Permanent water is important in South Australia, where drying wetlands led to an emergency rescue in 2007. Surrogate refuges in wetlands and farm dams have been used for captive-bred fish, but the documents do not define refuge dimensions or minimum water depth.

  • Treat permanent pools, wetland refuges and connected backwaters as potential refuges during dry periods and construction planning.
  • Do not dewater a wetland, pool or backwater without an approved assessment, rescue procedure and appropriate authorisations.

Threats: Clearing and construction impacts

The main risks are loss or degradation of shallow, vegetated freshwater habitat, altered hydrology, sediment and poor water quality, and introduced fish. Small isolated populations can be lost from a single severe event and may not recolonise because the species does not disperse long distances.

Clearing aquatic plants, emergent reeds, riparian vegetation, snags, rocks, timber debris or undercut banks can remove shelter, feeding areas and spawning surfaces. Bank disturbance, dredging, barriers and sediment-producing works can damage habitat, increase turbidity, smother eggs and restrict fish passage.

  • Map occupied and potential habitat before works, including wetland margins, backwaters, low-flow pools, aquatic vegetation and connected channels.
  • Avoid clearing or disturbing aquatic and riparian vegetation wherever practicable, and stage any approved works outside the breeding and dependent early-life period.
  • Install and maintain effective erosion and sediment controls before ground disturbance, and inspect them after rainfall.
  • Prevent construction barriers from blocking fish passage or isolating wetland and backwater habitat.
  • Do not remove large woody debris, rocks or snags without assessing their habitat function and obtaining the required approvals.

Threats: Hydrology and water quality

Reduced flows, river regulation, fluctuating water levels, loss of wetland inundation, salinity, agricultural runoff, siltation, livestock access and thermal pollution degrade habitat and can reduce reproduction and recruitment. At Third Reedy Lake, proposed reduction from permanent water to inundation about one year in five was identified as a severe risk.

Third Reedy Lake hydrology risk: The Victorian assessment identified a proposed change from a permanently wet system to one wetted about one year in five.

  • Maintain environmental flows, water levels and wetland inundation needed for aquatic vegetation and spawning habitat.
  • Keep sediment, nutrients, contaminants and heated water out of waterways and wetlands.
  • Restrict livestock access to vulnerable stream banks where it causes turbidity or bank damage.

Threats: Introduced fish and isolation

Eastern gambusia, redfin perch and common carp threaten the species through predation, competition or habitat disturbance. Carp can stir sediments and smother eggs. Small isolated populations have limited gene flow and may not be naturally recolonised after local extinction.

  • Prevent the spread of introduced fish between waterways and follow state rules for pest fish control.
  • Do not release aquarium, bait or translocated fish into natural waterways.
  • Maintain habitat connectivity where it can be achieved without moving fish between genetically distinct populations or breaching an approved recovery plan.

Threats: Other threats

The supplied documents do not identify a species-specific disease threat, fire response, road mortality pattern or road-crossing behaviour. These risks should still be considered where roads, culverts, crossings, fire management or contaminated water could affect the species' freshwater habitat, but site assessment is needed before assigning significance.

  • Inspect proposed crossings, culverts, drains and temporary water diversions for effects on flow, fish passage, turbidity and aquatic vegetation.
  • Include waterway protection and fish rescue procedures in incident and emergency planning where works could isolate or dewater habitat.

Survey methodology: 1. Habitat inspection

Survey the species as a small, non-migratory, demersal fish of permanent or persistent freshwater habitat. It is cryptic and difficult to catch, so survey planning must cover suitable habitat and allow for imperfect detection.

Inspect all slow-moving or still water within and downstream of the work area, including wetlands, billabongs, backwaters, low-flow pools and small to medium streams.

Map dense aquatic vegetation, overhanging bank vegetation, leaf litter, rocks, timber debris, undercut banks, mud, sand and gravel because these features provide cover or spawning substrate.

Give particular attention to permanent water and weedy pools where water temperature can exceed 20 degrees Celsius during the breeding period.

Survey methodology: 2. Targeted fish sampling

Use an appropriately authorised freshwater fish survey team to sample suitable habitat identified during the inspection, including vegetated margins, cover and low-flow areas.

Select capture methods that can safely sample small demersal fish while limiting damage to aquatic plants, banks and retained habitat. Follow the relevant state fisheries permit and animal ethics requirements.

Plan sampling for warmer water conditions, when the species commonly spawns. The documents describe spawning in spring or summer when water temperatures are above 20 degrees Celsius.

Survey methodology: 3. Repeat coverage and identification

Repeat targeted sampling where the first visit produces no fish but suitable habitat is present, because the species is cryptic, demersal and difficult to catch.

Record the location, date, waterbody, water conditions, method, sampling duration, number of people, equipment, capture results and photographs of any suspected fish.

Confirm identification using photographs and an appropriately qualified fish ecologist. Useful features include the rounded head and tail, two dorsal fins, red and white body spots, blue or purple colouration, and, in New South Wales, three red-maroon cheek bars.

Survey methodology: Minimum effort and reporting

Breeding period: Spring or summer, with spawning when water temperature is above 20 degrees Celsius.

Known Victorian mature population estimate: 8 to 40 mature individuals at the assessment date, with exact abundance unknown.

  • Use a risk-based survey design that covers every suitable waterbody and all aquatic habitat proposed for disturbance, because the supplied documents do not prescribe a standard number of nights, hours, trap nights, transects or sampling area for this species.
  • Increase repeat effort where habitat is suitable, populations may be small or isolated, or a negative result would affect the project approval decision.
  • Do not treat a single negative survey as proof of absence where suitable habitat remains, because the species is difficult to detect and Victorian sampling found only eight fish after extensive effort.
  • Submit confirmed records and negative targeted survey results to the relevant state wildlife or biodiversity database, and report sightings through the relevant state threatened species reporting system.
  • Retain survey data, photographs, permits, animal handling records, environmental conditions and the names and qualifications of survey personnel in the project file.

Before habitat disturbance: Avoid and minimise

Avoid disturbing occupied water and retain the physical features that support shelter, feeding and spawning. Treat any suitable wetland, backwater, slow-flowing pool or vegetated stream as potential habitat until a qualified survey and approvals process show otherwise.

  • Keep permanent and slow-flowing water, wetland edges, aquatic plants, overhanging vegetation, undercut banks, rocks, leaf litter and timber debris outside the disturbance footprint wherever practicable.
  • Avoid changes to water levels, seasonal inundation, flow, turbidity, salinity and water quality, because these factors affect habitat, reproduction and recruitment.
  • Retain aquatic and riparian connectivity between occupied or suitable pools, wetlands and backwaters, because isolated populations have limited gene flow and the species cannot readily disperse long distances.
  • Do not place sediment, spoil, fuel, concrete washout or other pollutants where runoff can enter retained water.

Before habitat disturbance: Approvals and planning

  • Check whether the action requires an EPBC Act referral because the species is nationally listed as Endangered.
  • Check the applicable state threatened species, fisheries, scientific collection, animal ethics, waterway, vegetation clearing and relocation requirements before survey, capture or works begin.
  • Prepare a fauna management plan that identifies aquatic habitat, survey results, exclusion zones, water quality controls, stop-work triggers, authorised handlers, contingency habitat and reporting responsibilities.
  • Schedule works to avoid the warmer spring and summer breeding period where practicable, particularly where works could disturb spawning substrates, eggs or newly hatched fish.

Before habitat disturbance: Site preparation

  • Complete a pre-clearance aquatic habitat inspection and targeted fish survey before finalising the work footprint.
  • Mark retained waterways, wetland margins, aquatic vegetation, snags, rocks, undercut banks and no-go areas on plans and in the field.
  • Install exclusion fencing or other clearly visible controls where they can prevent machinery, vehicles, spoil and people entering retained aquatic habitat without diverting water or damaging banks.
  • Stage works so that habitat is disturbed only when the relevant authorised ecologist or fauna spotter catcher is present and the approved controls are operating.

During habitat disturbance: Daily controls and machinery interface

Use a stop, check and proceed system around every retained or disturbed waterbody. The fauna spotter catcher must work with the operator and aquatic ecologist, not as a substitute for fish survey or fisheries approvals.

  • Inspect exclusion fencing, sediment controls, water levels, flow paths and retained aquatic habitat before work starts each day and after heavy rain or an unexpected discharge.
  • Keep machinery, refuelling, washdown, spoil, concrete and stockpiles outside retained water and its agreed protection area.
  • Use a spotter catcher or aquatic fauna specialist to brief operators before each stage, define the exclusion zone and give a clear stop signal when fish, eggs, habitat damage or uncontrolled runoff is detected.
  • Progress from the least disturbing work to the most disturbing work, and stop machinery before entering any area that has not been checked.

During habitat disturbance: Habitat feature handling

  • Do not remove aquatic plants, snags, rocks, leaf litter or overhanging and undercut bank cover unless the approved method specifically requires it.
  • Do not dredge, fill, drain, isolate or rapidly dewater habitat without an approved aquatic fauna procedure and an authorised person present.
  • If rocks, timber or aquatic vegetation must be moved, inspect each item for fish, eggs and larvae, keep it wet, minimise handling and place it in retained or approved replacement habitat as soon as practicable.
  • Maintain low turbidity and prevent livestock, vehicles and works from damaging stream banks or adding sediment to the water.

During habitat disturbance: If the species is found

  • Stop work in the immediate area and keep machinery, people and silt-laden water away from the fish and its habitat.
  • Do not allow untrained workers to catch, retain, buy, sell, possess or move the fish.
  • Have only the person authorised under the relevant permit or approval assess, capture or relocate the fish, using the approved method and equipment.
  • Relocate a fish only where the approval and fauna management plan allow it, and use nearby retained habitat with suitable slow or still water, cover and aquatic vegetation.
  • Record the location, time, photographs, condition, identification, action taken and destination for every fish, egg mass or suspected record.
  • Send an injured fish to an appropriately authorised aquatic wildlife carer, veterinarian or government contact under the approved incident procedure.

During habitat disturbance: Stop-work triggers

  • Stop work if a southern purple-spotted gudgeon, eggs, larvae or an occupied suitable refuge is found in the disturbance area.
  • Stop work if water becomes turbid, polluted, saline, rapidly dewatered or disconnected from retained habitat, or if sediment controls fail.
  • Stop work if exclusion zones are breached, an unauthorised person handles fauna, or the approved capture, relocation or dewatering procedure cannot be followed.
  • Notify the project environmental officer and relevant regulator or permit holder, then obtain written or documented direction before restarting.

After habitat disturbance: Completion checks

Do not close out aquatic works when machinery leaves the site. Confirm that retained habitat remains functional, controls are stable and all fauna and water quality incidents have been resolved.

  • Inspect the work area, downstream habitat and any temporary isolation or dewatering zone for stranded fish, eggs, larvae, trapped water and damaged aquatic vegetation.
  • Remove temporary barriers, pumps, pipes and debris only after the authorised aquatic fauna specialist confirms that fish passage and safe water levels have been restored.
  • Check that retained pools, wetlands and backwaters have suitable cover, low-flow or still-water conditions and no new barriers to movement.
  • Repair bank damage, sediment controls and fencing before demobilisation.

After habitat disturbance: Monitoring and reporting

  • Monitor water quality, turbidity, water levels, flow, aquatic vegetation and fish passage at the frequency set by the approval or fauna management plan.
  • Undertake follow-up targeted fish surveys where habitat was altered, fish were captured or relocated, water levels changed, or an incident occurred.
  • Report confirmed records, mortalities, injuries, captures, relocations, habitat damage, permit breaches and corrective actions to the relevant regulator and state biodiversity database.
  • Keep monitoring records and photographs that show whether the retained or restored habitat is functioning.

After habitat disturbance: Ongoing controls and offsets

  • Maintain exclusion fencing, sediment controls, water quality controls and access restrictions until the environmental officer confirms that the site is stable.
  • Prevent new carp, redfin perch and eastern Gambusia from entering retained or restored habitat through uncontrolled water transfers or fish movement.
  • Where residual impacts cannot be avoided or minimised, obtain advice on any EPBC Act or state offset, compensation or recovery action required by the approval.

Rehabilitation actions: Wetland and bank restoration

Rehabilitation should recreate permanent or persistent freshwater habitat with dense cover, firm spawning surfaces and low-flow or still-water conditions. Design the works for this species rather than treating revegetation as a generic site finish.

  • Reinstate slow-flowing or still-water areas, wetland and backwater habitat where the approved hydrology allows, and avoid a design that leaves the site dry for long periods.
  • Plant or protect submerged aquatic vegetation such as water ribbon and foxtail, emergent reeds such as club rushes, and suitable overhanging edge grasses.
  • Retain or reinstate rocks, timber debris, snags, leaf litter and undercut bank cover, placing them where they provide refuge without blocking fish passage.
  • Use erosion and sediment controls until banks and aquatic plants are established, and prevent agricultural runoff, siltation and livestock access from degrading the restored water.

Rehabilitation actions: Predator and weed management

  • Remove or control introduced redfin perch, carp and eastern Gambusia under the relevant fisheries and biosecurity approvals.
  • Prevent carp from stirring sediment and smothering eggs, and prevent introduced predatory fish from occupying restored refuge areas.
  • Control weeds and protect planted aquatic vegetation without removing native cover used for feeding, shelter and breeding.
  • Do not release captured native fish or introduced fish unless the approved authority specifically directs the action.

Rehabilitation actions: Fire and physical protection

  • Protect permanent water, wetland margins, aquatic plants, snags and riparian cover from fire suppression works, vehicle access and unplanned burning.
  • Use a site-specific fire plan prepared with the relevant land manager because the supplied species documents do not prescribe a fire interval, season or intensity for this fish.
  • Keep firebreaks, access tracks and drainage works from isolating pools, removing riparian cover or increasing sediment delivery to the water.

Rehabilitation actions: Success measures

Breeding indicators: Sticky egg clusters on rocks, wood or broad-leafed plants, guarded and fanned by the male; eggs hatch in about 3 to 9 days depending on water temperature.

Habitat target: Permanent or persistent slow-flowing or still water with aquatic vegetation, cover and suitable firm substrates.

  • Monitor whether water remains present through the intended dry period, aquatic plants establish, cover and spawning substrates remain in place, and turbidity and water quality stay within approval limits.
  • Use repeat targeted fish surveys to assess occupancy, recruitment and persistence, recognising that absence from a single survey does not demonstrate absence.
  • Record fish size classes, breeding evidence, egg or larval observations, habitat condition, introduced fish detections and any barriers to movement.
  • Review the rehabilitation plan if monitoring shows loss of water, aquatic vegetation, spawning substrate, connectivity or native fish, and report outcomes to the relevant regulator and biodiversity database.

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