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Dalhousie Hardyhead (Craterocephalus dalhousiensis)

The Dalhousie Hardyhead is a small freshwater fish found only in the Dalhousie Springs complex in northern South Australia. Its very small range and dependence on artesian spring flows make it a high-priority species for clearing, construction and water management projects. It is listed as Critically Endangered under Commonwealth conservation arrangements and occurs within an Endangered Ecological Community under the EPBC Act 1999.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Breeding season

Wild breeding timing for the Dalhousie Hardyhead has not been established. For planning in northern South Australia, assume adults, eggs and young may be present in spring pools and outflows at any time, and use targeted fish surveys before disturbance.

Breeding mode: Sticky eggs are scattered over aquatic vegetation or the substratum in aquaria. The wild breeding site is not recorded.

Breeding season: Not recorded.

Egg number: A few eggs per day were recorded in aquaria when water temperatures were above 24°C. Total wild egg production is not recorded.

Incubation period: Not recorded.

Larval and juvenile development: Not recorded.

Age at maturity: Not recorded.

Timing may vary with spring temperature, flow and local conditions, and the absence of recorded seasonal data means risk should be managed consistently between years and across the Dalhousie Springs complex.

  • Potential breeding in warm spring habitat: No wild seasonal pattern is known, so breeding should be treated as possible throughout the year where suitable warm water persists.
  • Eggs and early life stages: Eggs may be attached to vegetation or the substratum, but the timing and duration of this stage are not recorded.
  • Adult presence in spring pools and outflows: Treat the species as present year round in occupied springs, including deeper habitat, unless current survey results demonstrate otherwise.
  • Highest clearing risk: For this Commonwealth critically endangered species, avoid assuming a low risk season, survey occupied or potentially suitable springs with a qualified freshwater fish ecologist, and protect spring flows, water quality, vegetation and aquatic habitat before works begin.

Identification: Appearance and size

The Dalhousie Hardyhead is a small, streamlined fish. Identification can be difficult because it closely resembles Glover’s Hardyhead, and species boundaries between the two forms require further investigation.

The body is brownish, with a distinctive greenish or dark mid-lateral stripe. There is usually one band of spots above the stripe and three bands below it.

Adults grow to about 80 mm. Like the other endemic fishes of Dalhousie Springs, it is a small fish and should be handled carefully during any authorised aquatic survey.

Body form: Streamlined

Maximum recorded size: About 80 mm

Distinctive markings: Dark or greenish mid-lateral stripe, usually with one band of spots above and three bands below

Identification: Sex differences

Mature males and females can show different body profiles. A mature female has a sloping, concave profile from the snout to the first dorsal fin and a flat underside from the gills to the pelvic fins.

A mature male has an almost straight dorsal profile and a gently arched underside. These features are most useful for mature fish and should not be used alone for field identification.

Identification: Similar species

Glover’s Hardyhead is morphologically similar and can be difficult to distinguish from the Dalhousie Hardyhead. The two species occur together in one spring system, so location alone may not confirm identification.

Use an experienced freshwater fish ecologist or suitable taxonomic specialist where identification affects a development decision. Retain photographic and measurement records and follow permit conditions for any capture or handling.

  • Do not assume every hardyhead in a warm Dalhousie spring is a Dalhousie Hardyhead.
  • Record the spring, pool or outflow where each fish was detected.
  • Treat uncertain hardyhead records as potentially significant until confirmed.

Identification: Calls and field signs

This species has no known field call or echolocation feature used for detection. It leaves no reliable terrestrial signs such as droppings, nests, whitewash or odour.

Detection is based on direct observation or authorised aquatic sampling. Fish may be associated with deeper parts of the spring system, so shallow-edge observations alone may underestimate their presence.

Distribution: Australian range

The Dalhousie Hardyhead is endemic to the Dalhousie Springs complex in northern South Australia. Its distribution is exceptionally restricted, so a small area of works can affect a substantial part of the known range.

The species is known only from the Dalhousie Springs complex in South Australia. Dalhousie Springs covers about 70 km² and contains approximately 80 active springs, occurring as isolated springs or small groups.

A 1985 study recorded the species from seven springs. Later surveys did not always identify hardyheads to species level, so historical site counts should be interpreted carefully.

  • State: South Australia.
  • Region: Dalhousie Springs, in the northern South Australian desert.
  • Known distribution: Approximately seven springs in the Dalhousie Springs complex.

Distribution: Overseas range

The Dalhousie Hardyhead is an Australian endemic. There is no overseas range.

Distribution: Site planning implications

A spring, outflow or connected wet area within the Dalhousie Springs complex should be treated as potential habitat. This applies even where fish have not been recorded recently or where a survey has identified hardyheads only to genus level.

Map spring sources, pools, outflows, connecting channels and access routes before finalising clearing or construction footprints. Keep works, vehicle movements and stock access away from aquatic habitat unless they have been specifically assessed and approved.

  • Confirm the location of each proposed activity against the spring complex and protected-area boundaries.
  • Check whether works could alter groundwater pressure, spring flow, water temperature or water quality.
  • Escalate any proposed disturbance near occupied or potentially occupied springs for species and ecological-community assessment.

Habitat: Spring features to look for

The species depends on permanent or persistent groundwater-fed spring habitat in an otherwise dry landscape. It appears to favour deeper habitat in moderate to large warm springs, including both pools and flowing sections.

Look for spring sources, warm pools and outflows fed by Great Artesian Basin groundwater. The species uses habitats where water provides an isolated refuge from the surrounding desert.

Potential habitat may include deeper pools and sections of outflow where water remains above 20°C. Spring-source temperatures are reported at about 35 to 40°C.

  • Moderate to large spring pools.
  • Warm spring outflows.
  • Deeper aquatic areas.
  • Persistent groundwater discharge.
  • Vegetated aquatic margins and submerged vegetation, particularly where spawning habitat may occur.

Habitat: Surrounding landform and vegetation

Dalhousie Springs is a restricted spring ecosystem surrounded by arid country. Vegetation dynamics can alter aquatic habitat, especially where Common Reed or Date Palms expand into spring channels and shallow areas.

Assess the whole spring unit, not just the proposed work pad. Include the source, pool, outflow, margins, access tracks and any areas where runoff, sediment or altered drainage could enter the water.

Habitat: Habitat condition

Good habitat has stable groundwater discharge, suitable water temperature, adequate depth and intact aquatic vegetation. Habitat can be degraded by trampling, pollution, excavation, excessive reed growth or changes in spring flow.

Avoid disturbing the spring bed or margins. Prevent sediment, fuel, concrete washout, nutrients and other contaminants from entering pools or outflows.

Foraging habitat: Feeding areas

Dalhousie Hardyheads feed in spring pools and outflows. Their diet includes green filamentous algae and small aquatic invertebrates, so water quality and aquatic plant structure should be retained.

Inspect deeper pools, warm outflows and vegetated edges for potential feeding habitat. Green filamentous algae and small aquatic invertebrates may occur on submerged surfaces and among aquatic vegetation.

The species may forage across both still and flowing parts of a spring. Avoid assuming that a bare or shallow margin is the only relevant area.

  • Submerged vegetation.
  • Algal growth on aquatic surfaces.
  • Warm spring pools.
  • Flowing channels and outflows.
  • Deeper water containing aquatic invertebrates.

Foraging habitat: Development risks to feeding habitat

Clearing aquatic vegetation, infilling pools, diverting flow or increasing turbidity can reduce feeding habitat. Changes to groundwater discharge can also remove the warm, permanent conditions on which the species depends.

Use contained work areas and prevent machinery, spoil, dust, sediment and chemical products from entering the spring system. Keep vehicle access on established routes where access is permitted.

  • Do not excavate or deepen spring channels without a specific approval and ecological assessment.
  • Do not remove aquatic vegetation unless authorised and supported by a management plan.
  • Control runoff and prevent polluted water from reaching pools or outflows.

Breeding habitat: Spawning features

Wild breeding sites and breeding seasons are poorly understood. Hardyheads scatter sticky eggs over vegetation, so submerged plants and stable aquatic habitat should be protected throughout the year.

In aquaria, eggs are scattered over vegetation or the substrate rather than placed in a nest. Similar vegetation or substrate use may occur in the wild, but the natural breeding site has not been confirmed.

Treat submerged vegetation, shallow margins and stable substrate within occupied springs as potential breeding habitat. Do not disturb these features during routine works.

  • Submerged or emergent aquatic vegetation.
  • Vegetated spring margins.
  • Stable substrate in pools and outflows.
  • Warm water with persistent flow or depth.

Breeding habitat: Breeding timing

The timing of wild spawning is not established. Do not rely on a seasonal clearance window to avoid breeding impacts.

Plan work on the assumption that breeding habitat may be in use at any time. If fish are detected, stop work that could affect the water or spring margin and seek advice from the project ecologist and relevant authorities.

Breeding habitat: Protection during works

Avoid clearing, dredging, trampling or placing materials in aquatic habitat. Maintain water quality and spring flow while works are underway.

Any capture, handling, relocation or disturbance of fish must be undertaken only by appropriately authorised personnel and under the relevant permits and approvals.

  • Fence or otherwise control access to sensitive spring margins where authorised.
  • Keep spoil, fuels and construction materials outside the spring drainage area.
  • Inspect aquatic equipment and use appropriate decontamination procedures to reduce disease and pest transfer.

Sheltering habitat: Likely refuge areas

The species uses isolated spring refuges and appears to be associated with deeper habitat. Specific shelter structures and group sizes are not established, so all connected aquatic habitat should be treated cautiously.

Potential refuge areas include deeper pools, spring-source channels and sections of warm outflow with stable water levels. Aquatic vegetation and changes in depth may provide cover.

Spangled Perch, the only other fish recorded at Dalhousie Springs, occupies larger and deeper springs and may influence the distribution of the endemic fishes.

  • Deep pools and channels.
  • Spring sources and warm outflows.
  • Vegetated aquatic margins.
  • Areas protected from trampling and rapid flow changes.

Sheltering habitat: Site controls

Keep people, machinery, stock and vehicles out of aquatic habitat wherever practicable. Use designated access points and avoid crossing spring channels.

Do not pump, drain, divert or obstruct spring water without prior assessment and approval. A minor change in flow or water level can affect a highly localised population.

  • Mark no-go areas around pools and outflows before works begin.
  • Use aquatic biosecurity procedures for nets, boots, pumps and other equipment.
  • Report fish mortality, sudden turbidity, reduced flow or unexpected drying immediately.

Threats: Groundwater drawdown and spring drying

The species is highly exposed to local impacts because its entire known range is concentrated in a small number of springs. Development and land management should focus on protecting groundwater discharge, water quality, aquatic vegetation and the absence of introduced fish.

Reduced artesian pressure and groundwater extraction can reduce spring flows or cause springs to dry. Water allocation, bore use, pumping and construction activities that affect groundwater require careful assessment.

Avoid activities that could lower groundwater pressure or redirect spring discharge. Include the spring ecosystem in groundwater and cumulative-impact assessments.

  • Assess changes to groundwater levels and artesian pressure.
  • Protect natural spring discharge and flow paths.
  • Monitor for reduced flow, shrinking pools or drying margins.

Threats: Physical disturbance and water pollution

Trampling by livestock, feral animals, workers or vehicles can damage spring margins and shallow aquatic habitat. Excavation, stock access and pollution from faeces, nutrients, ammonia, sediment or construction materials can also degrade habitat.

Use exclusion areas, controlled access and spill prevention. Do not excavate springs or improve stock access through aquatic habitat without specific approval.

  • Keep machinery and stock away from pools and outflows.
  • Prevent sediment, fuel, chemicals and concrete washout entering water.
  • Repair or isolate damaged access points promptly under ecological advice.

Threats: Vegetation change

Common Reed can expand after changes in grazing management and reduce shallow aquatic habitat. Date Palms and other vegetation changes can also alter spring structure, flow and available fish habitat.

Vegetation control should be planned with a freshwater ecologist. Do not clear aquatic plants or remove woody or palm vegetation from a spring margin without assessing effects on fish and the broader spring community.

  • Map reed and palm expansion before treatment.
  • Retain aquatic vegetation that may support feeding or spawning.
  • Use targeted, monitored control rather than broad unplanned clearing.

Threats: Introduced fish, disease and visitation

Introduced fish, particularly Gambusia, could compete with hardyheads, behave aggressively or introduce disease. Dalhousie Springs is reported to remain free of exotic fish, so prevention is preferable to eradication.

Tourism and unmanaged visitation can damage spring margins and water quality. Use clean equipment, control access and report any suspected exotic fish immediately.

  • Do not release or move fish between springs.
  • Decontaminate nets, footwear, waders and other aquatic equipment.
  • Manage visitor and contractor access to prevent trampling and accidental introductions.
  • Escalate any suspected Gambusia or unusual fish mortality without delay.

Survey methodology: 1. Desktop assessment

Survey this species as a small freshwater fish confined to the Dalhousie Springs complex in northern South Australia. Identification can be difficult, especially where Glover’s Hardyhead occurs, so use experienced aquatic ecologists and confirm uncertain records with a recognised fish taxonomist.

Map all springs, pools and warm outflows that could be affected by the proposal. Check records for Dalhousie Hardyhead and Glover’s Hardyhead, spring discharge, water extraction, grazing, reed growth, access tracks and previous disturbance.

Treat every connected spring and outflow as potentially important habitat. The species has been recorded from about seven springs and may occupy deeper water in moderate to large springs with warm outflows.

  • Obtain current threatened-species records from South Australian authorities and the relevant land manager.
  • Review the proposal for changes to groundwater, spring flow, drainage, water quality, vegetation, access and visitor use.
  • Engage the approval authority early if works could affect a spring, its outflow or Great Artesian Basin groundwater.

Survey methodology: 2. Aquatic detection survey

Use non-destructive visual searches, underwater observation and appropriately permitted fine-mesh nets or seines where these can be used without damaging spring habitat. Sample pools and outflows, including deeper areas and warm water above 20°C where safe and suitable.

Avoid disturbing vegetation, substrates and spring vents. Do not remove fish, eggs or aquatic plants unless the survey team holds the required authority and the method has been approved.

Use eDNA or other environmental sampling as a supplementary method where suitable. Treat a negative result as inconclusive unless the method, sampling design and seasonal conditions support that conclusion.

  • Survey in clear, stable conditions when water levels and access allow safe observation.
  • Repeat surveys where detection is uncertain, habitat is turbid or the species cannot be separated confidently from Glover’s Hardyhead.
  • Have a species identification expert review photographs or records where the two hardyheads may be confused.

Survey methodology: 3. Timing and effort

Wild breeding timing and seasonal movements are poorly known. There is no confirmed migration period or reliable breeding calendar, so do not assume that a spring is free of breeding fish outside a particular season.

Set survey effort according to the number and isolation of springs, habitat complexity, water clarity and the potential consequence of disturbance. Survey every spring and outflow that could be directly or indirectly affected, rather than relying on a nearby representative site.

  • Use more than one visit where the first survey may have missed fish or where works could affect a high-value spring.
  • Coordinate aquatic surveys with the works program so results remain current when clearing, excavation, pumping or construction begins.
  • Stop and reassess if water temperature, flow, clarity or access conditions change substantially between survey and construction.

Survey methodology: 4. Field records

Record the exact spring, pool or outflow location and map the area surveyed. Record observed fish numbers or abundance categories, water depth, temperature, flow, clarity, vegetation, substrate and the presence of other fish, including Spangled Perch and Gambusia.

Photograph habitat and representative fish where this can be done without handling them. Record the method, equipment, time, weather, surveyors, survey duration and any limitations.

  • Record all signs of eggs, larvae, spawning activity, injured fish, dead fish, exotic fish and habitat damage.
  • Keep records for each spring separately. Do not combine observations across isolated springs.
  • Submit records promptly to the project ecologist and relevant authorities, with sensitive locations handled in accordance with data-sharing requirements.

Before habitat disturbance: 1. Avoidance and approvals

Avoid spring habitat wherever practicable. The species is restricted to northern South Australia, and small local changes can affect an isolated population, so project design should protect the spring, its outflow and the groundwater conditions that sustain it.

Redesign works to avoid springs, pools, outflows, aquatic vegetation and areas that could alter groundwater discharge. Keep vehicles, stockpiles, fuels, concrete washout, sediment and wastewater away from aquatic habitat.

Assess direct and indirect impacts under the Environment Protection and Biodiversity Conservation Act 1999. Seek an EPBC referral where the action may have a significant impact on the listed species or the groundwater-dependent ecological community.

Confirm South Australian approvals before survey, collection, handling, pumping, construction or disturbance. The species occurs in Witjira National Park, where collection requires appropriate permits.

  • Confirm land tenure, park approvals, access permissions and any National Parks and Wildlife Act 1972 requirements.
  • Obtain approval for any fish capture, handling, transport, tissue collection, marking or relocation before work starts.
  • Do not rely on a general fauna handling licence if a separate aquatic, park or threatened-species authority is required.

Before habitat disturbance: 2. Site-specific exclusion controls

Establish a clearly marked no-go area around each affected spring, pool and outflow. Set the boundary with the aquatic ecologist and approval authority because no standard species-specific buffer is established for this fish.

Protect the full area needed to maintain spring flow, water quality, aquatic vegetation and deeper refuge habitat. Include indirect pathways such as groundwater drawdown, altered drainage, sediment entry, trampling and changes to grazing.

  • Fence or barricade exclusion areas before machinery arrives.
  • Use designated access routes and washdown areas outside the catchment of the spring and outflow.
  • Prohibit groundwater pumping, dewatering, water diversion and excavation near the spring unless specifically assessed and approved.
  • Install sediment and spill controls before earthworks and inspect them after rain.

Before habitat disturbance: 3. Pre-clearance aquatic check

Complete a final aquatic inspection immediately before disturbance of any spring or outflow. Confirm that the approved footprint, exclusion controls and emergency contacts are in place.

If fish, eggs, larvae or suitable habitat are found outside the approved footprint, stop the relevant activity and obtain advice from the aquatic ecologist before proceeding.

  • Check water flow, pool depth, water quality, aquatic vegetation and access conditions.
  • Use the approved survey method to confirm whether Dalhousie Hardyhead or Glover’s Hardyhead is present.
  • Do not drain, isolate, fill or disturb a waterbody to make the inspection easier.

Before habitat disturbance: 4. Breeding and crew induction

Hardyheads scatter sticky eggs over vegetation or the substratum in captivity, but wild breeding places and timing are poorly known. Treat vegetated shallow margins, submerged vegetation and suitable substrates as potential breeding habitat throughout the works period.

There is no confirmed migration season. Plan works to avoid any period of spawning or juvenile presence identified by the survey team or approval conditions.

  • Induct every worker on the species, its restricted distribution, the exclusion areas and the stop-work process.
  • Show workers photographs or identification guidance for both Dalhousie Hardyhead and Glover’s Hardyhead.
  • Require workers to report fish, eggs, larvae, dead fish, spills, sediment entry and damaged fencing immediately.
  • Disinfect and dry aquatic equipment between waterbodies under the project biosecurity procedure.

During habitat disturbance: 1. Sequential works

Use a staged, low-disturbance approach. A qualified aquatic fauna spotter catcher or other authorised person must control fish handling and have clear authority to stop work.

Work from the least sensitive areas towards the approved footprint. Complete protection measures and inspect each stage before starting the next.

Keep spring flows running unless an approved method specifically allows temporary change. Avoid sudden changes in water level, flow, temperature, clarity or oxygen conditions.

Do not enter aquatic habitat with machinery unless the approval explicitly allows it and the aquatic ecologist has confirmed the method.

  • Clear terrestrial vegetation first and keep all debris out of the water.
  • Use hand tools near spring edges where practicable.
  • Maintain spill kits, sediment controls and clean equipment at the work front.
  • Stop pumping or excavation immediately if spring discharge changes or cloudy water enters habitat.

During habitat disturbance: 2. Spotter catcher authority

The aquatic spotter catcher must inspect each work area before disturbance and remain available while activities could affect fish or aquatic habitat. The person must have authority to stop work without waiting for routine supervisory approval.

Only authorised and trained personnel may capture, handle, identify, contain or relocate fish. Minimise handling time and keep fish in clean, aerated water at a temperature appropriate to the source habitat.

  • Stop work for any fish, egg, larva, unexpected spring discharge, damaged exclusion control or pollution event within or near the work area.
  • Do not move fish between springs unless this is specifically approved and directed by the relevant authority.
  • Do not release fish into a different spring, pool or outflow as an informal rescue action.
  • Use clean, dedicated equipment and prevent contact with chemicals, sediment and untreated water.

During habitat disturbance: 3. Breeding places and concentrations

If eggs, larvae, spawning fish or a concentrated group of fish are found, stop work in the affected area. Protect the habitat and seek direction from the project ecologist and approval authority.

The species has no known colony, nest or roost structure. For this fish, treat the spring, pool, aquatic vegetation and substratum containing eggs as the breeding place and protect it from disturbance.

  • Mark the location without entering the water or disturbing vegetation.
  • Establish or extend the exclusion area as directed by the aquatic ecologist.
  • Do not remove eggs or vegetation containing eggs unless an approved rescue or research procedure is in place.
  • Resume work only after the authorised ecologist confirms that controls meet approval conditions.

During habitat disturbance: 4. Injured or dead animals

If an injured fish is found, stop nearby work and contact the authorised aquatic fauna handler. Keep the fish in the source water only if the handler directs this and suitable clean equipment is available.

Do not attempt treatment or release without authority. Report dead fish, unusual mortality, disease signs or exotic fish immediately.

  • Record the location, time, condition, photographs and likely cause without delaying required notification.
  • Follow the project wildlife incident pathway and any instructions from South Australian authorities or the park manager.
  • Contain contaminated equipment and suspend aquatic work if disease or exotic fish are suspected.

During habitat disturbance: 5. Daily records

Keep a daily record of inspections, fish observations, captures, releases, incidents, water conditions, exclusion breaches and stop-work events. Link every record to a mapped spring or work area.

  • Record the names and authorities of all people handling fish.
  • Record the number and apparent condition of animals handled, the source and release location, and any mortality.
  • Report incidents and permit breaches to the project manager and relevant authority within the time required by the approval.

After habitat disturbance: 1. Post-clearance checks

Complete a careful post-clearance inspection before demobilising aquatic controls. Continue checking the springs where works could have changed habitat, water quality or fish movement.

Inspect the entire approved footprint and all adjoining exclusion areas for stranded fish, eggs, larvae, dead fish, sediment, spills, rubbish, damaged vegetation and altered flow.

Check spring vents, pools and outflows after pumping, excavation, heavy rain or any event that could change water conditions.

  • Use the aquatic fauna handler for any live fish or egg response.
  • Remove debris and repair controls without entering sensitive habitat unless authorised.
  • Leave exclusion fencing in place until the aquatic ecologist confirms that the risk has ended.

After habitat disturbance: 2. Relocated animals

Where relocation was approved, check the release location and confirm that fish were released only into the authorised source or destination habitat. Do not assume that a relocated fish has survived or established.

Record follow-up observations and any mortality. Report failed releases or unexpected movements to the approval authority.

  • Use the approved release method and location exactly as specified.
  • Do not supplement or restock a spring with captive-bred or transferred fish without a separate approved conservation program.
  • Include relocation outcomes in the completion report.

After habitat disturbance: 3. Monitoring

Set monitoring around the risk of the action. Monitor flow, water quality, aquatic vegetation and fish presence where construction may have affected a spring, outflow or groundwater condition.

Because the species is confined to isolated springs and its breeding and movement patterns are poorly known, use repeat monitoring designed by an aquatic ecologist rather than a single visual check.

  • Compare results with pre-work records from the same spring and survey locations.
  • Increase monitoring if abundance declines, habitat dries, reed growth expands, exotic fish appear or water conditions change.
  • Continue monitoring for the period required by the approval, management plan or adaptive monitoring trigger.

After habitat disturbance: 4. Reporting and incident review

Prepare a completion report covering methods, effort, locations, fish records, breeding observations, incidents, controls, water conditions, rehabilitation and any permit conditions.

Review every stop-work event, mortality, spill, exclusion breach and unexpected habitat change before the next work stage or project phase.

  • Map all impact areas and retained habitat.
  • Document corrective actions, responsible people and completion dates.
  • Update the site environmental management plan and induction material where controls were ineffective.
  • Notify the relevant authority of significant impacts or incidents as required.

Rehabilitation actions: 1. Restore aquatic habitat

Restore spring function first, then restore vegetation and access controls. Rehabilitation must protect the groundwater discharge, warm outflows, deeper refuge habitat and aquatic vegetation used for feeding and spawning.

Remove temporary structures, sediment, rubbish and contaminated material without disturbing the spring or outflow. Reinstate natural flow paths and pool connections where works have altered them.

Use locally appropriate aquatic and riparian plants only where planting is approved and will not change spring flow or introduce disease. Protect planted areas from trampling and grazing until established.

  • Prevent erosion and sediment entry from tracks, batters and drainage lines.
  • Do not deepen, excavate or reshape a spring to improve stock or machinery access.
  • Do not introduce fish, plants, water or substrate from another spring.
  • Use clean equipment and approved materials in all rehabilitation works.

Rehabilitation actions: 2. Vegetation and weeds

Control Common Reed, Date Palms and other invasive or overabundant vegetation where they reduce shallow aquatic habitat or alter spring function. Plan control with the land manager and aquatic ecologist.

Retain native aquatic vegetation and submerged structure that may provide feeding and spawning habitat. Avoid broad vegetation removal during control works.

  • Use manual or targeted methods near water where practicable.
  • Prevent herbicide, cut vegetation and soil from entering the spring.
  • Inspect treated areas for regrowth and unintended loss of aquatic cover.
  • Coordinate weed management with grazing and visitor management.

Rehabilitation actions: 3. Exclusion, water and lighting

Maintain fencing, gates and designated access routes that prevent livestock, feral animals, vehicles and visitors from trampling spring margins. Manage stock access so it does not cause faecal pollution, nutrient input or bank damage.

Avoid lighting directed at springs and outflows. Use only the minimum lighting needed for safety, shield it from water and switch it off when not required.

  • Keep fuel, chemicals, waste and washdown areas outside the spring drainage area.
  • Do not allow construction water, stormwater or groundwater with altered quality to enter habitat.
  • Inspect fences and drainage controls after rain and repair them promptly.

Rehabilitation actions: 4. Replacement breeding structures

Nest boxes, bat boxes, artificial nests and roost structures do not suit this fish and should not be installed. The species scatters eggs on vegetation or the substratum, so the appropriate replacement is functioning natural aquatic habitat, not a structure.

Any artificial spawning substrate, captive breeding, supplementation or translocation should be designed and approved as a specialist conservation or research action.

  • Prioritise clean, flowing spring habitat with suitable aquatic vegetation and substratum.
  • Do not place artificial materials in a spring without approval and a disease and habitat-risk assessment.
  • Remove experimental structures if they trap fish, collect debris or alter flow.

Rehabilitation actions: 5. Long-term management

Monitor restored springs for fish presence, water flow, water quality, aquatic vegetation, reed growth, grazing pressure and exotic fish. Use the results to adjust access, weed control, water management and visitor controls.

Keep rehabilitation records with the spring location, treatment, date, responsible contractor, monitoring results and corrective actions.

  • Maintain habitat protections for the life of the project and any approval period.
  • Investigate any reduction in artesian pressure, spring flow or water quality promptly.
  • Report new populations, suspected range changes, mortality and exotic fish to the relevant South Australian authority.
  • Review the management plan after each monitoring period and after any extreme dry period or major disturbance.

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