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Spotted Galaxias (Galaxias truttaceus)

The Spotted Galaxias is a small galaxiid fish of coastal streams, lakes and slow flowing rivers in southern Australia. The Western Australian population, recognised in the supplied sources as the subspecies Galaxias truttaceus hesperius, is restricted to the Goodga and Angove River systems near Albany and is highly sensitive to barriers, introduced fish, salinity, sedimentation and increased water temperature. Stream works, crossings, clearing and altered runoff can affect breeding migration, cover and water quality.

Conservation status

Commonwealth, EPBC Act 1999: Endangered.

Western Australia, Biodiversity Conservation Act 2016: Endangered.

Breeding season

The calendar below combines the Western Australian breeding information with the better documented general and Tasmanian life cycle. Timing can vary between coastal and landlocked populations, so local records should guide survey and construction timing.

Month values are January to December. A value of 0 means not typical, 1 means occurs, and 2 means peak or highest expected activity. Timing is best confirmed from local surveys, particularly in Western Australia.

  • Breeding and spawning: Spawning is reported in autumn and early winter for the Western Trout Minnow, and from autumn to winter for coastal populations generally. Adults move downstream and deposit adhesive eggs in freshwater on submerged vegetation, twigs or leaves.
  • Eggs and early larvae: The Tasmanian account reports hatching after up to about four weeks. Larvae are carried downstream and then use marine or connected lacustrine nursery habitat.
  • Larval and juvenile movement: In the Tasmanian life cycle, larvae spend about three to four months at sea and juveniles return to freshwater as whitebait in late spring. The Western Australian survey guidance also identifies estuarine or lacustrine stages for larvae and young juveniles.
  • Freshwater growth and feeding: Juveniles and adults remain in freshwater habitat, feeding around logs, boulders, aquatic vegetation and pool margins. The Western Australian taxon has negligible growth during warmer months.
  • Highest clearing risk: The highest direct risk is during autumn and early winter spawning, when adults move through streams and eggs are attached to freshwater cover. Disturbance can also affect larvae and juveniles during downstream or return movements from late autumn through spring, so instream isolation and sediment-producing works should be avoided across this wider period where occupied habitat is present.

Identification

Confirm identification from body shape, colour pattern, habitat and locality. Records from Western Australia require particular care because the threatened Western Trout Minnow occurs with other small galaxiids.

The Spotted Galaxias is a small, stout fish with a long head and a large mouth extending back to below the front of the eyes. The back is brown to deep olive, the sides are brownish grey and the belly is silvery.

Large, round purplish spots with pale halos occur on the sides and upper back. The fins are brown to orange and the tail is slightly forked. The fish is scaleless.

Typical adult length: 120 to 140 mm

Maximum recorded size in the general species accounts: About 200 mm

Western Australian maximum stated in the listing advice: 12 to 14 cm

Identification: Similar galaxiids

In south-western Western Australia, the Western Trout Minnow may occur in the same broad region as the Common Galaxias, Galaxias maculatus, and the Western Galaxias, Galaxias occidentalis. The supplied survey guidance states that its distinctive colour pattern allows separation, but field records should still be confirmed by an experienced freshwater fish ecologist.

Do not rely on a photograph of a single small or poorly marked fish where a threatened Western Australian population may be present. Record the locality, waterbody, fish length, markings, habitat and identification features, and retain voucher material only under the relevant permit and animal ethics requirements.

Identification: Field signs and handling

There are no reported tracks, scats, calls, nests, sloughs or eyeshine signs for this fish. Presence is normally demonstrated by capture or direct observation in suitable freshwater habitat.

Fish may shelter beneath logs and boulders, among submerged aquatic vegetation and beside bank overhangs. During breeding movements, fish may collect in lower stream sections when low flows prevent further downstream movement.

  • Treat shallow coastal streams, pool margins, undercut banks and in-stream cover as potential habitat even when fish are not seen during a daytime inspection.
  • Use non-destructive methods where practicable, including small scoop nets, visual observation and appropriately managed electrofishing by qualified personnel.
  • Minimise handling time and return captured fish to the same waterbody after identification and recording.

Distribution: National range

Galaxias truttaceus occurs in southern Australia, including coastal parts of Victoria, Tasmania, South Australia and south-western Western Australia. The Western Australian taxon has a much smaller distribution than the species as a whole.

The species is recorded from Western Australia, South Australia, Victoria and Tasmania, and from King Island, Flinders Island and Clarke Island in Bass Strait. The Tasmanian account describes it as widespread and abundant on the Tasman Peninsula, where it occurred in both slow and fast flowing streams.

In Victoria, the supplied field guide describes the natural range as coastal streams. It also notes a suspected introduced population in the upper Campaspe and Loddon rivers and a single whitebait record from the lower Murray River near Wentworth.

States and territories with records in the supplied sources: Western Australia, South Australia, Victoria and Tasmania

Bass Strait islands listed: King Island, Flinders Island and Clarke Island

Relevant broad bioregional settings: Coastal streams of southern Australia, including the Albany area, Tasmanian coastal catchments and coastal Victorian catchments

Distribution: Western Australian strongholds

The Western Australian population is restricted to the Goodga River system in and immediately outside Two Peoples Bay Nature Reserve, and to a 2 km section of the Angove River within Two Peoples Bay Nature Reserve and adjacent Crown reserve.

Historical records included the King and Kalgan rivers and streams west of Albany. Recent surveys did not locate the taxon in the King or Kalgan rivers, and records from the Pallinup and Fitzgerald rivers were considered to be misidentified Common Galaxias.

Current Western Australian locations: Goodga River system and a 2 km section of the Angove River

Combined stream length used in the area estimate: About 6 km

Estimated area of occupancy: About 0.012 km²

Estimated former range represented by the remaining 6 km: About 2 percent of the former Western Australian range, based on the listing advice

  • Treat the Goodga River and Angove River catchments near Albany as high priority habitat for survey and impact assessment.
  • Check downstream habitat and connected reaches when assessing works, because larvae and juveniles use estuarine or lacustrine environments and adults move within stream systems.

Distribution: Population status

The Western Australian taxon has undergone a major range contraction. The larger remaining population is in the Goodga River, while the viability of the Angove River population was uncertain in the listing advice because it was known from only six specimens in 2004 and had not been repeatedly surveyed.

A study cited in the listing advice estimated 1,000 to 2,500 mature Western Trout Minnow, with mature fish comprising about half of the total population. The listing advice also records that a fish ladder at a Goodga River weir doubled the available Goodga habitat from about 2 km to about 4 km.

Estimated mature Western Australian population: 1,000 to 2,500 individuals

Angove River record noted in the listing advice: Six specimens captured in 2004

Goodga habitat before the fish ladder: About 2 km below the weir

Goodga habitat after the fish ladder: About 4 km

Habitat: Waterbodies and stream form

Spotted Galaxias uses freshwater streams, rivers and lakes, especially where the margins contain dense cover. Coastal and lower elevation waters are important for the species, while the Western Australian taxon is confined to cool, acidic and non-saline streams near Albany.

The species occurs in still or flowing rivers, streams and lakes. In the eastern Australian habitat account, streams are generally shallow, less than 1.5 m deep, and narrow, between 0.5 and 5 m wide. Tasmanian study streams were short, generally less than 5 km long, and rarely exceeded 1 m deep except during peak flows.

The species is most common in lower elevation habitats close to the coast. It can occur in clear or turbid water, although the Tasmanian account reported the greatest numbers in clear water.

Typical stream depth in the eastern Australian account: Less than 1.5 m

Typical stream width in the eastern Australian account: 0.5 to 5 m

Tasmanian study stream length: Less than 5 km

Tasmanian study stream depth: Usually less than 1 m, except at peak flow

Habitat: Western Australian conditions

The Western Trout Minnow is known from the Goodga and Angove rivers near Albany. The Goodga River water is described as acidic and non-saline, with mean temperatures from 11.7 degrees Celsius in July to 20 to 23 degrees Celsius between November and March.

The taxon is confined to cooler climatic regions and has negligible growth during warmer months. Its upper lethal temperature tolerance is reported as 30 degrees Celsius.

Goodga River minimum mean water temperature: 11.7 degrees Celsius in July

Goodga River maximum mean water temperature: 20 to 23 degrees Celsius from November to March

Reported upper lethal temperature tolerance: 30 degrees Celsius

  • Protect cool water inputs, shaded stream reaches, connected pools and natural low flow refuges.
  • Prevent sediment, warm stormwater, saline drainage and other construction runoff from entering occupied or connected stream habitat.

Habitat: Vegetation and structure

Important habitat features include aquatic vegetation, submerged logs, boulders, bank overhangs, riparian canopy and pool margins. The Tasmanian streams used by the species were shaded by dense riparian vegetation including Eucalyptus, Banksia and Acacia.

Fish were recorded beneath logs and boulders, among submerged aquatic vegetation and around the edges of pools. These features provide cover for adults and juveniles and should be retained through stream crossings and bank works.

  • Map and retain logs, boulders, aquatic vegetation, undercut banks and riparian shade within the project area and downstream impact area.
  • Avoid de-snagging, channel straightening, unnecessary bank grading and removal of submerged or marginal vegetation.

Foraging habitat: Diet and feeding areas

Adults feed in streams and lakes, using structurally complex margins and the water surface. The diet includes aquatic insect larvae, other aquatic invertebrates and terrestrial insects that fall from riparian vegetation.

Larval fish in lake nursery areas feed exclusively on surface plankton before migrating back to the river system. Juveniles and adults feed predominantly on terrestrial insects falling onto the water surface, as well as aquatic insect larvae and other aquatic invertebrates.

The species forages around logs, boulders, aquatic vegetation, bank overhangs and pool margins. Dense riparian vegetation can provide a continuing supply of terrestrial insects to the water.

Larval food in lake nursery areas: Surface plankton

Adult and juvenile food: Aquatic insect larvae, aquatic invertebrates and terrestrial insects falling onto the water

Reported foraging structure: Logs, boulders, aquatic vegetation, bank overhangs and pool margins

  • Retain overhanging riparian vegetation and undisturbed pool margins where insects enter the water.
  • Prevent fine sediment and excessive turbidity from covering aquatic vegetation, boulder habitat and shallow feeding areas.
  • Assess connected lakes, lagoons and estuarine reaches where larvae or young fish may occur.

Foraging habitat: Foraging range and connectivity

No home range or daily foraging distance is given in the supplied documents. The fish remains associated with freshwater habitat but moves between stream sections during its life cycle, including downstream movement for spawning and movement of larvae or young fish through estuarine or lacustrine environments.

Barriers can concentrate fish below structures and restrict access to upstream habitat. A Goodga River fish ladder was used by 100 to 200 fish per day, with up to 300 recorded on some days, showing that movement corridors can carry substantial numbers of fish.

Goodga fish ladder use: Usually 100 to 200 fish per day, with up to 300 recorded on some days

  • Treat culverts, weirs, temporary dams, ford crossings and dewatered work areas as potential movement barriers.
  • Maintain fish passage during construction and provide a suitable bypass or staged works method where a barrier cannot be avoided.

Breeding habitat: Breeding biology

Spotted Galaxias breeds in freshwater, generally above tidal influence, but its early life stages may use estuarine or marine habitat. Adults need connected stream reaches, suitable spawning cover and enough flow for downstream transport of larvae.

The species has a Type 3b life cycle in Tasmania. Adults spawn in freshwater, larvae are carried downstream and spend about three to four months at sea, and juveniles return to freshwater as whitebait. The Western Trout Minnow is reported to spawn in autumn and early winter, while the general species account describes coastal populations breeding from autumn to winter.

Spawning occurs on submerged vegetation or dead twigs and leaves. Eggs are adhesive and hatch after about four weeks in the Tasmanian account. The Western Australian listing advice states that the breeding population is generally restricted to fish aged two years or more.

Breeding season: Autumn to winter, with the Western Australian taxon reported to spawn in autumn and early winter

Egg number: About 1,000 to 16,000 eggs in the general species account

Egg size: About 1.0 to 1.3 mm in diameter

Incubation: Up to about four weeks in the Tasmanian account

Age at maturity: About two years in the Tasmanian account; the Western Australian breeding population is generally fish aged two years or more

Larval marine period: About three to four months in the Tasmanian life cycle account

Lifespan: No lifespan estimate is provided for the general species in the supplied documents. Fish over 180 mm in Tasmania were considered to be about eight years old.

Breeding habitat: Breeding habitat features

Breeding habitat includes freshwater reaches above tidal limits with submerged vegetation, dead twigs, leaves, logs, boulders, shallow pools and intact riparian cover. Adults move downstream during the breeding period and may be held up in lower pools when low flows prevent movement.

Successful recruitment depends on maintaining passage between spawning reaches, downstream nursery areas and the coast or connected lakes. Weirs and other barriers can restrict spawning migration and reduce the available breeding area.

  • Avoid instream works, bed disturbance and bank clearing during autumn and early winter where occupied habitat is present.
  • Retain submerged vegetation, woody material and natural shallow pool margins that may carry adhesive eggs.
  • Keep downstream flow paths open during spawning and larval drift periods.
  • Include estuarine, lagoon and lake nursery habitat in the impact assessment where the stream connects to these environments.

Sheltering habitat: Recorded refuges

The species shelters in aquatic and marginal cover rather than in terrestrial refuges. Structural complexity is important for adults and juveniles, particularly in shallow streams and pool margins.

Fish are commonly found beneath logs and boulders, among submerged aquatic vegetation and beside bank overhangs on the edges of pools. Dense riparian canopy shades the water and contributes woody debris and terrestrial insects.

The supplied sources do not provide a required log diameter, boulder size, refuge density or minimum riparian buffer width. These features should therefore be mapped and retained on a site by site basis rather than reduced to a generic offset.

Stream depth associated with general habitat: Usually less than 1.5 m in the eastern Australian habitat account

Stream width associated with general habitat: About 0.5 to 5 m in the eastern Australian habitat account

  • Retain in-stream logs, boulders, aquatic plants, undercut banks and pool edge cover.
  • Do not place spoil, rock, sediment or construction materials in pools, undercut banks or shallow margins.
  • Use temporary exclusion fencing to keep plant, machinery and pedestrian access away from occupied stream margins.

Sheltering habitat: Nursery and refuge connectivity

Larvae and young juveniles use estuarine or lacustrine environments before returning to freshwater. Adults and juveniles can shelter in shallow pools and around cover, while low flows may concentrate fish in lower reaches.

Temporary isolation caused by dewatering, cofferdams, culverts or sediment dams can remove access to shelter and strand fish. Fish rescue and relocation should be planned with the relevant authority before any instream isolation.

  • Survey upstream and downstream of proposed crossings, not only the construction footprint.
  • Maintain connected wetted habitat or implement an approved fish rescue method before dewatering.
  • Inspect pools below weirs and temporary barriers because fish may accumulate there.

Threats: Clearing and construction

The main risks are loss of connected stream habitat, barriers to movement, introduced fish, warmer or more saline water, sedimentation and loss of riparian and in-stream cover. These risks are particularly serious for the restricted Western Australian taxon.

Clearing riparian vegetation can increase water temperature, reduce terrestrial insect inputs, remove bank cover and increase erosion. Stream channelisation, de-snagging and siltation have been associated with reduced fish numbers, reduced species diversity or degraded native fish habitat in the supplied studies.

Road construction, crossings, trenching, bank works and stormwater discharge can introduce sediment, alter flow paths or create temporary barriers. These effects may extend downstream beyond the cleared area.

  • Keep machinery, spoil, concrete washout, fuels and sediment controls out of the channel and flood-prone margins.
  • Stage works to maintain downstream flow and fish passage.
  • Use erosion and sediment controls that remain effective during rainfall and protect shallow pools and spawning substrates.
  • Avoid removing riparian canopy, bank overhangs, logs, boulders and aquatic vegetation unless an approved impact assessment demonstrates that removal is unavoidable.

Threats: Barriers and hydrology change

Weirs can restrict upstream spawning migration and can concentrate fish below the structure, increasing exposure to bird predation. The Goodga River fish ladder increased available habitat from about 2 km to about 4 km.

Dams, impoundments, altered seasonal flows and flow reversal can interrupt movement, change spawning access and reduce the shallow flowing habitat used by the species. Increased salinity in the King and Kalgan rivers was identified as a possible cause of local loss.

  • Assess fish passage at every culvert, weir, ford, temporary crossing and water control structure.
  • Do not assume that a structure is passable because water is flowing through it.
  • Maintain natural seasonal flow cues during spawning and downstream larval movement where practicable.
  • Assess salinity, temperature, turbidity and dissolved oxygen before, during and after works where the taxon may occur.

Threats: Introduced fish, predators and disease

Rainbow Trout, Brown Trout, Redfin Perch and Mosquitofish are identified threats through predation, aggression or competition. Mosquitofish occur in private property dams within the Goodga catchment and could reach occupied streams during flooding or accidental release.

The cestode Ligula intestinalis has been recorded in the Western Trout Minnow. It can cause gonadal retardation, deformities and reduced swimming ability. About 7 percent of juvenile fish were infected in one study, increasing vulnerability to bird predation.

Juvenile infection rate reported for Ligula intestinalis: About 7 percent in one study

Introduced fish identified as threats: Rainbow Trout, Brown Trout, Redfin Perch and Mosquitofish

  • Prevent transfer of live fish, water, mud and aquatic equipment between catchments.
  • Clean and disinfect sampling and construction equipment before moving between waterbodies.
  • Report suspected introduced fish or diseased native fish through the relevant state agency.
  • Do not stock farm dams or connected waters with fish without approval from the relevant fisheries authority.

Threats: Fire, roads and fragmentation

The supplied documents do not identify a direct fire response or a fire-specific refuge for Spotted Galaxias. Fire can still affect occupied habitat indirectly where it removes riparian shade, increases post-fire erosion or changes runoff and water temperature.

Roads and infrastructure can fragment stream habitat through culverts, crossings, sediment delivery and altered drainage. The risk is greatest where a project affects one of the few connected reaches available to the Western Australian taxon.

  • Plan firebreaks, access tracks and post-fire stabilisation to avoid direct disturbance to stream banks and riparian canopy.
  • Inspect road crossings for perched outlets, scour, blocked culverts and sediment pulses after rainfall or fire.
  • Treat the Goodga and Angove river systems as highly sensitive to fragmentation because the remaining populations are isolated.

Survey methodology: 1. Define the survey area and habitat

Confirm the taxon before surveying. The western Western Australian population is treated in the supplied government material as Galaxias truttaceus hesperius, Western Trout Minnow, whereas the broader species is Galaxias truttaceus, Spotted Galaxias. The methods below apply to projects that may affect the Western Australian population or suitable habitat for the species.

Map the project footprint and all areas that could be affected indirectly, including downstream reaches, wetlands, lakes, estuaries and access tracks.

Identify shallow, narrow streams, pools, lake margins and connected downstream habitat. The Western Australian population is known from the Goodga and Angove river systems, while the species more broadly uses coastal streams, lakes and still or slow-flowing water.

Record habitat features including logs, rocks, submerged vegetation, bank overhangs, riparian canopy, barriers, weirs, culverts and areas of suitable stream connectivity.

Known Western Australian range of the subspecies: Goodga River system and a 2 kilometre section of the Angove River, in and near Two Peoples Bay Nature Reserve

Recorded Western Australian stream length in the listing advice: Approximately 6 kilometres combined across the Goodga and Angove rivers

Estimated area of occupancy in the listing advice: 0.012 square kilometres

  • Inspect the project area and downstream receiving habitat before selecting survey sites.
  • Treat habitat as potentially suitable where water is shallow, generally less than 1.5 metres deep, and the channel is narrow, generally 0.5 to 5 metres wide, with cover along the margins.
  • Check whether the site connects to estuarine or lacustrine habitat because larvae and young juveniles use those environments in the Western Australian population.

Survey methodology: 2. Daytime stream and margin sampling

Use small scoop nets, seine nets, sweep nets, funnel traps and, where authorised, electrofishing to sample streams, pools, lake margins and connected shallow water.

The survey guideline reports that the Western Trout Minnow is most common during the day, although larger individuals were taken at night. Sample both open water and cover around logs, rocks, vegetation and bank margins.

Reported seine net lengths: 1, 5, 10 and 26 metres

Reported seine net fishing depth: Up to 1.5 metres, except where site conditions require less

Reported larval tow net: Conical net with an 800 millimetre diameter and 500 micrometre mesh

Spawning period reported for the Western Trout Minnow: Autumn and early winter

  • Use seine nets with fine mesh where water depth and access allow; methods reported for this taxon used 3 millimetre mesh nets, with the largest net having 6 millimetre mesh wings.
  • Use sweep nets in shallow margins and around cover, taking care not to damage eggs, larvae or habitat.
  • Use funnel traps only where permitted and where the method is suitable for the site, because catch rates can be low for small plastic traps generally.
  • Use electrofishing only under an approved method, by trained operators, and at the lowest effective setting to minimise harm.

Survey methodology: 3. Larval, juvenile and night detection

Include larval tow sampling where connected estuarine or lacustrine habitat may be affected. The species has larvae and young juveniles in estuarine or lacustrine environments.

Add night sampling where the daytime survey does not provide adequate coverage or where larger fish may be missed. The survey guideline records larger individuals at night, although the species was most common during the day.

  • Sample the water column and shallow margins separately so that larval, juvenile and adult detections can be distinguished.
  • Repeat sampling across representative habitat units rather than relying on one point or one capture method.
  • Release captured fish promptly at the capture location unless an authorised handler is required to retain a specimen for identification or veterinary assessment.
  • Have an experienced fish ecologist confirm identification because the taxon can occur with Common Galaxias and Western Galaxias in south western Western Australia.

Survey methodology: Minimum effort and reporting

Set survey effort from the size and condition of the affected habitat, the potential for downstream impacts and the likelihood that fish use different habitats during their life cycle. The supplied documents do not prescribe a fixed number of nights, hours, trap nights or transect lengths for this taxon.

  • Use more than one appropriate method where habitat includes streams, pools, lake margins or estuarine connections.
  • Record survey dates, start and finish times, weather, water level, water temperature where measured, water quality observations, effort by method, net dimensions, electrofishing settings, habitat sampled and all captures or non-detections.
  • Photograph representative habitat and any fish that cannot be identified in the field without unnecessarily retaining the animal.
  • Submit verified records, including zero records where appropriate, to the relevant Western Australian wildlife database and the Australian Government threatened species records system.
  • Report suspected Western Trout Minnow records promptly to the project ecologist and the relevant state wildlife authority before works continue in the affected habitat.
  • Retain permits, ethics approvals, calibration records and the fauna handling log with the project environmental records.

Before habitat disturbance: Avoid and minimise habitat loss

Treat occupied streams and connected shallow-water habitat as sensitive before clearing, earthworks, crossings, dewatering or waterway modification. Confirm whether the project affects the broader Spotted Galaxias or the Western Australian subspecies, because their distributions and conservation listings differ.

Keep works out of occupied or suitable stream habitat wherever practicable. The Western Trout Minnow has a very restricted distribution and two isolated remaining populations in the Goodga and Angove rivers.

Retain shallow pools, stream margins, riparian cover, logs, rocks, submerged vegetation and bank overhangs used for shelter and feeding.

Maintain movement between freshwater, downstream reaches and estuarine or lacustrine habitat where the local population requires those connections.

Known remaining Western Australian populations in the listing advice: Goodga River and Angove River

Threats identified in the listing advice: Introduced fish, barriers to upstream spawning migration, salinity, sedimentation, elevated water temperature, parasites and bird predation

  • Do not place temporary crossings, spoil, sediment controls or stockpiles in the active channel or on fish shelter features unless no practicable alternative exists.
  • Avoid new barriers and design crossings to preserve upstream and downstream fish passage.
  • Prevent changes that increase salinity, sedimentation or summer water temperature, as these are identified threats to the Western Trout Minnow.
  • Use the smallest practicable disturbance footprint and retain the natural channel form and riparian shade.

Before habitat disturbance: Approvals and work planning

Check the EPBC Act status for the taxon and obtain project-specific advice before work starts. The supplied material identifies the Western Australian taxon as EPBC critically endangered, while the project brief identifies the species as EPBC endangered, so the taxonomic and listing position must be verified.

Check Western Australian wildlife, fish, waterway and threatened fauna permit requirements before capture, handling, relocation, electrofishing, dewatering or habitat disturbance.

Prepare a fauna management plan that identifies survey results, exclusion areas, approved methods, competent personnel, stop-work triggers, emergency contacts and reporting requirements.

  • Refer the action under the EPBC Act if the proposed action may have a significant impact on the nationally listed taxon.
  • Obtain any state approval required for work in a waterway, reserve, riparian area or fish habitat.
  • Stage works to keep a connected refuge and flow path available while other sections are treated.
  • Schedule in-channel work outside autumn and early winter where practicable, because that is the reported spawning period for the Western Trout Minnow.

Before habitat disturbance: Pre-clearance preparation

Complete a pre-clearance inspection immediately before works, including the channel, pools, wet margins, downstream refuge areas and any temporary access route.

Mark no-go habitat, retained riparian vegetation, fish passage routes, exclusion zones and all approved machinery access points on plans and on the ground.

  • Install exclusion fencing where it can keep machinery, people, spoil and sediment out of retained fish habitat.
  • Brief the fauna spotter catcher, operators and supervisors on the habitat map, approved work limits, fish identification and stop-work procedure.
  • Prepare clean equipment and prevent transfer of mud, water, fish, eggs and aquatic plants between catchments or waterbodies.
  • Plan dewatering so fish are not stranded and water quality, flow and downstream refuge are maintained.

During habitat disturbance: Daily controls and machinery coordination

Use active supervision wherever works could affect water, stream banks, riparian cover or fish passage. The fauna spotter catcher must have authority to pause work when fish, habitat or water quality controls are at risk.

Inspect exclusion fencing, sediment controls, flow bypasses, access points and retained habitat before the shift starts and after heavy rain or any incident.

Keep machinery, refuelling, concrete, chemicals, spoil and washdown water out of the channel and retained wet habitat.

Use a spotter catcher to maintain visual coverage of the work face and communicate directly with the plant operator and supervisor.

  • Stop or pause machinery before entering any area where a fish, stranded animal, damaged bank, failed sediment control or unexpected water connection is detected.
  • Work progressively in small sections so that fish can be detected and moved from the next work area before disturbance begins.
  • Do not discharge turbid, saline, contaminated or unusually warm water to occupied or connected habitat.
  • Maintain upstream and downstream passage during temporary works unless an approved fish rescue and dewatering procedure is in place.

During habitat disturbance: Handling fish and habitat features

Only trained and authorised personnel should capture, identify, handle or relocate fish. Use methods approved in the fauna management plan and relevant permits.

Keep handling time short and minimise air exposure, crowding, heat and physical contact. Release healthy fish into nearby retained habitat with suitable flow and cover, unless the permit or expert advice requires another destination.

  • Inspect shallow margins, pools, logs, rocks, aquatic vegetation, bank overhangs and isolated puddles before they are disturbed or dewatered.
  • Move logs and rocks only where authorised, and replace them in nearby retained habitat if they must be temporarily removed.
  • Do not disturb eggs, larvae or juvenile fish unnecessarily, particularly during the autumn and early winter spawning period.
  • If dewatering is unavoidable, use the approved fish rescue method, check isolated pools repeatedly and prevent fish from being trapped in pumps, sumps or low points.
  • Do not translocate fish between catchments or waterbodies without written authorisation.

During habitat disturbance: Animal finds, injury and stop-work triggers

If a suspected Spotted Galaxias or Western Trout Minnow is found, stop the relevant activity, protect the location from further disturbance and notify the fauna spotter catcher and project ecologist.

Have an experienced fish ecologist confirm identification where possible. The Western Trout Minnow can be confused with Common Galaxias and Western Galaxias in south western Western Australia.

  • Keep the animal in suitable water and handle it only under the approved permit and fauna management procedure.
  • Relocate a healthy animal only to nearby retained habitat that has suitable water quality, flow, depth, cover and connectivity, and only where authorised.
  • Send an injured animal to an appropriately qualified aquatic wildlife veterinarian or wildlife carer through the approved authority pathway.
  • Stop work if fish are found in the disturbance footprint, fish passage is blocked, fish are stranded, water quality deteriorates, a control fails, or the approved work limits are exceeded.
  • Resume work only after the fauna spotter catcher, project ecologist and site supervisor have documented the response and confirmed that controls are effective.

During habitat disturbance: Records and incident reporting

Record every capture, observation, rescue, relocation, injury, mortality, non-compliance, stop-work event and restart decision on the day it occurs.

  • Record the date, time, precise location, habitat, method, fish measurements where taken, photographs, identification confidence, handler, action taken and release location.
  • Record water level, visible turbidity, flow interruption, unusual temperature, salinity indicators and any introduced fish observed.
  • Notify the relevant state wildlife authority and the Australian Government regulator where a listed fish is injured, killed, relocated outside the approved area or affected by an unapproved action.
  • Update the project fauna register and submit verified records to the relevant state wildlife database.

After habitat disturbance: Post-clearance checks

Do not treat completion of earthworks as the end of the fauna obligation. Check the disturbed reach, retained habitat and downstream refuge, then verify that controls and fish passage continue to work.

Inspect the completed work area, upstream and downstream reaches, bypasses, culverts, banks and retained pools after each work stage and after the first substantial rainfall or flow event.

Search for stranded fish, blocked passage, sediment deposits, scour, bank collapse, loss of shade, damaged logs or rocks and new isolated pools.

  • Remove temporary barriers, pumps, pipes, spoil and access structures when no longer required, unless an approved design requires them to remain.
  • Repair failed erosion and sediment controls immediately and prevent contaminated or turbid water from entering retained habitat.
  • Complete a final fauna inspection before demobilisation and document any residual risk to fish movement or habitat.

After habitat disturbance: Monitoring and compliance reporting

Monitor occupied or potentially occupied habitat where the project changes flow, water quality, stream structure, riparian cover or fish passage.

Use the same survey methods and effort categories during follow-up monitoring where comparison with the pre-work survey is required.

  • Set monitoring dates and triggers in the fauna management plan, including checks during and after the autumn to early winter spawning period where relevant.
  • Compare detections, habitat condition, water quality observations and passage condition with the pre-work record.
  • Report listed fish records, injuries, deaths, unplanned impacts, corrective actions and monitoring results to the relevant state authority and under any EPBC approval conditions.
  • Maintain exclusion fencing, sediment controls, shade and fish passage measures until the site is stable and the project ecologist signs them off.
  • Apply approved offsets or other compensatory measures if residual impacts remain and an approval requires them.

Rehabilitation actions: Restore stream habitat and connectivity

Rehabilitation should restore connected, shaded freshwater habitat with cover and stable water quality. It should support movement between stream, pool and downstream environments rather than creating isolated wet areas.

Reinstate a natural channel profile, stable banks, shallow margins and pool habitat where works have altered the bed or banks.

Replace suitable logs, rocks and submerged woody cover in or beside the channel where they were removed and where their placement will not create an unsafe obstruction or new barrier.

Restore riparian canopy and bank vegetation to provide shade, bank stability and cover. The species uses logs, boulders, vegetation and bank overhangs for shelter.

  • Use local native riparian species suited to the site rather than planting vegetation that changes the channel or blocks fish passage.
  • Remove temporary barriers and confirm that culverts, crossings and fishways allow movement in both directions under the range of expected flows.
  • Do not construct isolated ponds as a substitute for connected stream habitat unless they form part of an approved habitat design and retain suitable fish passage.
  • Protect restored areas from stock, machinery, trampling, weed invasion and sediment delivery until vegetation and banks are stable.

Rehabilitation actions: Water quality, predators and introduced fish

Control sediment, salinity, chemical contamination and excessive warming because increased salinity, sedimentation and elevated water temperatures are identified risks to the Western Trout Minnow.

Prevent introduced fish from entering restored habitat. Rainbow Trout, Brown Trout, Redfin Perch and Mosquitofish are identified threats, and nearby dams may provide a pathway during flooding.

  • Use shade and riparian revegetation to reduce direct heating of shallow water.
  • Inspect restored habitat for introduced fish and report suspected introductions through the approved state pathway rather than moving or attempting to remove fish without authorisation.
  • Control weeds and maintain ground cover so that runoff does not fill pools or smother stream habitat.
  • Manage fire, access and fuels in accordance with the approved site plan so that riparian vegetation and stream banks are not repeatedly damaged.

Rehabilitation actions: Monitoring and success measures

Monitor restored reaches for fish presence, passage, pool persistence, water quality, riparian cover, bank stability, sediment accumulation and introduced fish.

Use the pre-disturbance habitat map and survey records as the baseline for judging whether the site is recovering.

Reported adult size of the broader Spotted Galaxias: Usually 120 to 140 millimetres, with a maximum of about 200 millimetres

Reported age at maturity in the Tasmanian study: About two years

Habitat cover recorded in the Tasmanian study: Logs, boulders and submerged aquatic vegetation

  • Confirm that retained and restored reaches remain connected during the periods when fish move upstream or downstream to breed.
  • Record whether logs, rocks, vegetation and bank overhangs remain available as cover.
  • Use repeat fish surveys by approved methods, with effort and timing recorded so that results can be compared between monitoring events.
  • Investigate a failure if fish are absent where they were previously recorded, fish passage is blocked, water quality declines, or restored habitat becomes dry, saline, highly turbid or overheated.
  • Continue monitoring for the period specified by the approval or fauna management plan and submit results to the relevant state wildlife database and regulator.

Sources