Fauna Spotters logo

Tapered Galaxias (Galaxias lanceolatus)

The tapered galaxias is a small, non-migratory freshwater fish known from a single subpopulation in the headwaters of Stoney Creek, a Thomson River tributary in West Gippsland, Victoria. It is Critically Endangered under the EPBC Act and is highly sensitive to trout invasion, sedimentation, fire, drought and changes to shallow stream habitat, so works near waterways, tracks and drainage lines require careful controls.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

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

Breeding season

The annual pattern below applies to the known Victorian population. Breeding timing is inferred, and movement is limited because the species is non-migratory.

Months are January to December. Breeding months are indicative because species-specific spawning observations are limited.

  • Breeding, spawning and egg development: Spawning is undocumented but is thought to occur from late winter to spring. Related mountain galaxias attach sticky eggs beneath rocks in riffles, with hatching after about 20 to 30 days.
  • Adult gonad development: About 70 percent of fish collected in early May were at an advanced stage of gonad development, and some males were running ripe.
  • Larvae and young fish: The exact timing for tapered galaxias is unknown. Related mountain galaxias larvae hatch at about 9 mm after eggs develop for 20 to 30 days.
  • Highest clearing risk: Clearing and ground disturbance can affect habitat in every month through sediment, altered runoff and loss of riparian cover. Risk is highest from late winter to spring when spawning, eggs and early life stages may be present, and after fire or heavy rainfall when sediment delivery can increase.

Identification

The tapered galaxias is a small, elongate galaxiid of cool, shallow headwater streams. Identification should be confirmed by an appropriately experienced freshwater fish ecologist because it was previously included within the unresolved mountain galaxias complex.

The body is elongate, tubular and scaleless, with a lateral line and evenly arched dorsal and ventral profiles. The back and upper sides are brown to grey-brown, the lower sides are brown to tan, and the underside is light brown to cream. Diffuse brown blotches and narrow vertical to chevron bars overlay the body, with a faint band of gold flecks along the mid-side. Juveniles are paler.

The head and snout are small and flattened. The mouth is large, the eyes are copper coloured, and the rounded soft-rayed fins are translucent grey. The gill cover is translucent and has a small golden patch.

Typical length: 65 to 70 mm length to caudal fin.

Maximum recorded size: 84 mm length to caudal fin and 6 g.

Body: Elongate, tubular and scaleless, with an evenly arched dorsal and ventral profile.

Identification: Distinguishing features

Within the mountain galaxias complex, the tapered galaxias is distinguished by its comparatively flattened head and snout, elongate body and evenly arched dorsal and ventral profiles.

FishBase also describes a broadly flattened dorsal midline anteriorly, a flat head profile anterior to the nape, high and long caudal peduncle flanges, and no black bars along the lateral line. These features should be assessed by a trained fish specialist rather than used as a stand-alone identification in the field.

Dorsal soft rays: 9 to 11.

Anal soft rays: 10 to 12.

Vertebrae: 53 to 55.

Identification: Field detection

There are no reported terrestrial field signs such as tracks, scats, nests, calls, sloughs or eyeshine. Detection is by direct fish capture or observation in the stream, usually during targeted freshwater fish surveys, and may also use eDNA where validated methods are available.

Individuals have been captured mainly around or among cobble in shallow, gently flowing riffles and glides. They are almost absent from still water near banks and deep pools, so absence from those habitats does not by itself rule out the species.

  • Treat any small galaxiid from suitable Stoney Creek headwater habitat as potentially significant until identified by a qualified freshwater fish ecologist.
  • Do not move captured fish between waterways, equipment or sites without approved biosecurity and translocation procedures.

Distribution: National range

The species is endemic to Victoria and has an extremely restricted known distribution. No confirmed population is recorded outside the upper Stoney Creek system.

The tapered galaxias is known only from the headwaters of Stoney Creek, a tributary of the Thomson River in West Gippsland, Victoria. The occupied stream lies at approximately 340 to 545 m above sea level, within the Thomson River Basin and Mitchell Thomson River region.

The known site is in State Forest. The species has not been recorded elsewhere in the Thomson or La Trobe catchments, further downstream in Stoney Creek, or in Glenmaggie Creek, Mt Useful Creek or the surveyed tributaries listed in the conservation advice.

States recorded: Victoria only.

Bioregional setting: West Gippsland, Thomson River catchment, Thomson River Basin and Mitchell Thomson River region.

Elevation: Approximately 340 to 545 m above sea level.

Distribution: Known subpopulations and strongholds

One extant subpopulation is known in the upper reaches of Stoney Creek, extending for about 12 km from upstream of Stoney No. 5 Track to 2.5 km downstream of Stoney No. 4 Track. The fish has been collected from several sites between Stoney No. 4 Track and Stoney No. 5 Track.

A waterfall or other natural instream barrier separates the occupied headwaters from downstream reaches where brown trout occur. The barrier is therefore an important refuge boundary and must not be weakened, bypassed or drowned out by works, sediment or altered flows.

A Galaxias sp. specimen was reported from Glenmaggie Creek in 1988, but it was not retained and the identity remains unconfirmed. Two translocations to a trout-free reach of Glenmaggie Creek East Branch were unsuccessful, with no individuals surviving.

Distribution: Population size and trend

The population is small, isolated and declining. A structured expert assessment reported about 1,200 mature individuals and a decline of more than 90 percent over the preceding 10 years. The current conservation advice also records density declines after fire-related sedimentation and drought stress.

The single population structure means that a local incident can affect the entire known range. Further surveys of Thomson River headwaters are required to determine whether additional subpopulations remain.

Known subpopulations: One confirmed extant subpopulation.

Estimated mature individuals: Approximately 1,200, based on the available expert assessment.

Recent trend: More than 90 percent decline over 10 years reported in the structured assessment.

Estimated occupied reach: Approximately 12 km of stream.

Estimated area of occupancy: Approximately 0.02 km².

Habitat: Stream habitat

The tapered galaxias occupies small, cool, clear, slow-flowing headwater streams in forested catchments. Its habitat is narrow and shallow, and the local catchment that supplies surface and groundwater is part of the habitat needed for its survival.

Recorded habitat is a creek about 0.5 to 1.5 m wide and 0.1 to 0.5 m deep. The water is clear, cool and slow flowing, within a forested catchment.

The bed is predominantly cobble, with some gravel, bedrock and sand. Rock provides most of the instream cover, with smaller amounts of undercut bank, timber debris and overhanging vegetation.

Average stream width: 0.5 to 1.5 m.

Average stream depth: 0.1 to 0.5 m.

Recorded fish microhabitat: Usually shallow riffles or glides, about 0.15 to 0.20 m deep, with gently flowing water.

Main substrate: Cobble, with gravel, bedrock and sand.

Habitat: Catchment and physical limits

Habitat critical to survival includes the occupied stream, adjoining reaches with similar habitat, potential trout-free translocation sites and the local catchment supplying surface and groundwater.

The species is non-migratory and cannot readily recolonise after local loss. Maintain riparian vegetation and drainage-line protection across wet and dry channels, including headwater drainage lines, because sediment and altered runoff can affect habitat downstream.

  • Keep soil, spoil, ash, chemicals and sediment out of the entire drainage network connected to occupied or potentially suitable headwater habitat.
  • Protect cobble riffles, shallow glides, undercut banks, woody debris, overhanging vegetation and the natural trout barrier from disturbance.
  • Plan crossings and temporary access routes to avoid direct sediment delivery and changes to low flows.

Foraging habitat: Diet and feeding sites

The species is expected to feed within the stream bed and water column of shallow riffles and glides. Its diet has not been directly reported, so the following diet is inferred from other mountain galaxias and related galaxiids.

The tapered galaxias is likely to be macroinvertivorous. Expected prey includes benthic, drifting aquatic and terrestrial invertebrates such as insects, crustaceans, molluscs, worms and spiders.

The fish is most often associated with cobble on the stream bed in shallow, gently flowing riffles and glides. These areas provide likely access to benthic prey, drifting food and cover. Still water near banks and deep pools are not typical capture locations.

Known diet: Not directly reported.

Likely diet: Benthic, drifting aquatic and terrestrial invertebrates.

Likely prey groups: Insects, crustaceans, molluscs, worms and spiders.

Foraging habitat: Cobble beds in shallow, gently flowing riffles and glides.

Foraging habitat: Foraging range

No foraging range has been measured. The species is non-migratory and is known from a short headwater reach, so feeding is expected to occur within and near occupied stream sections rather than across a broad catchment.

Sedimentation can cover cobble and reduce benthic food availability, refuge and spawning habitat. Works should therefore protect both the occupied channel and upstream drainage sources that deliver water and sediment.

  • Avoid disturbing cobble riffles and glides, even where fish are not immediately visible.
  • Prevent fine sediment, concrete washout, hydrocarbons and other pollutants from entering the stream because they can reduce prey habitat and water quality.

Breeding habitat: Breeding biology

Breeding information for the tapered galaxias is limited. The timing is inferred from gonad condition and related mountain galaxias, while egg and larval details are based mainly on other members of the species complex.

Spawning is undocumented for the tapered galaxias but is thought to occur from late winter to spring. In early May, about 70 percent of sampled individuals were at an advanced stage of gonad development, and some males were running ripe.

Related mountain galaxias have low fecundity, with fewer than 400 eggs annually. Their sticky eggs are generally attached to the underside of rocks in riffles. The eggs are about 2 mm in diameter, spherical, demersal and adhesive, and hatch after about 20 to 30 days. Related larvae are about 9 mm long at hatching.

Spawning season: Undocumented for this species, but thought to be late winter to spring.

Egg number: Not recorded for this species. Related mountain galaxias produce fewer than 400 eggs annually.

Egg attachment: Likely attached to the underside of rocks in riffles, based on related mountain galaxias.

Egg size and incubation: About 2 mm diameter and 20 to 30 days to hatch in related mountain galaxias.

Larval size at hatching: About 9 mm in related mountain galaxias.

Age at maturity: Not recorded.

Lifespan: Not recorded.

Generation length: Likely 2 to 4 years, based on other mountain galaxias.

Breeding habitat: Breeding habitat and work controls

Potential breeding habitat includes shallow, gently flowing cobble riffles and glides, especially where rocks provide surfaces for adhesive eggs. Fine sediment can smother substrate and reduce spawning habitat.

The breeding stream is small and shallow, so works that increase turbidity, alter low flows, remove cobble, disturb banks or reduce riparian shading may affect eggs, larvae and adults. All life stages are vulnerable to post-fire water quality impacts because the species is non-migratory.

  • Avoid in-channel works and bed disturbance in occupied or potentially occupied riffles and glides.
  • Keep riparian vegetation and overhanging cover intact during clearing and construction.
  • Use sediment and erosion controls before works begin, and inspect them after rainfall and high-flow events.

Sheltering habitat: Known refuges

The species shelters among stream-bed cobble and in other small instream structures. No species-specific measurements are available for refuge dimensions.

Individuals were captured mainly around or among cobble on the stream bed. Rock, small amounts of undercut bank, timber debris and vegetation overhang provide recorded instream cover.

Galaxiid species may burrow into coarse substrate when surface water levels decline. This behaviour may provide temporary refuge during drought, but fine sediment can fill the spaces between cobbles and remove that refuge.

Primary refuge: Cobble on the stream bed.

Other cover: Rock, undercut banks, timber debris and vegetation overhang.

Refuge dimensions: Not recorded for this species.

Pool use: Individuals were almost absent from deep pools and still water near banks during reported sampling.

Sheltering habitat: Refuge protection

The natural waterfall barrier below the known population also functions as protection from brown trout. Sedimentation, high flows, drought or works that alter the channel may reduce its effectiveness and allow trout incursion.

Maintain coarse stream-bed material, natural banks, riparian shade, low-flow connectivity and the integrity of the barrier. Do not introduce artificial refuge structures or move fish without agency approval and a species-specific conservation plan.

  • Keep machinery, spoil, sediment and temporary crossings out of the channel and refuge areas.
  • Check that access tracks and crossings do not create pathways for trout movement or illegal fish release.
  • Use strict aquatic biosecurity for footwear, nets, electrofishing equipment, pumps and other equipment moved between waterways.

Threats: Introduced trout and other fish

The tapered galaxias has one small known population, so threats that affect a short section of headwater stream can affect the species nationally. Introduced trout are the highest priority threat, with sediment, fire, drought and catchment disturbance increasing the risk of habitat loss and trout invasion.

Brown trout occur downstream of the natural barrier below the known population. Brown and rainbow trout prey on galaxiids, and all size classes of tapered galaxias are within the reported optimal prey size range for brown trout, 3 to 97 mm.

Trout can also compete for food and shelter. High flows, fire-related sedimentation, barrier damage, illegal stocking and accidental or deliberate fish movement may allow trout to enter the occupied reach.

  • Do not stock, release or transfer non-native fish or untreated water into any connected waterway.
  • Maintain and inspect natural or artificial barriers and report any trout detection immediately to the relevant Victorian land and fisheries authorities.
  • Prevent vehicle, equipment and angler access arrangements from creating pathways for unauthorised fish movement.

Threats: Clearing, roads and sediment

Timber harvesting, road and track maintenance, stream crossings and unsealed access routes can mobilise sediment or pollutants into the drainage network. Sediment can smother cobble, reduce food, refuge and spawning habitat, and increase turbidity.

Tracks also provide access that may increase the risk of illegal trout introduction. The conservation advice recommends vegetated protection zones along the entire drainage network, including wet and dry channels and headwater drainage lines.

  • Avoid clearing or soil disturbance beside occupied streams, tributaries, drainage lines and wet or dry headwater channels.
  • Design crossings to prevent direct sediment input and maintain natural flow paths.
  • Keep spoil, slash, concrete washout, fuel, herbicide and other contaminants away from drainage lines.
  • Stabilise exposed soil promptly and inspect erosion controls after rainfall.

Threats: Fire, drought and hydrology change

Fire can increase water temperature and sediment, reduce dissolved oxygen, alter water chemistry and smother stream substrate. Fire and high rainfall can also drown out or weaken barriers, allowing trout to move upstream.

Drought and reduced rainfall can lower water levels, increase temperature, create new barriers and prevent movement between suitable patches. Extreme rainfall can erode banks, increase sedimentation and alter flows.

  • Provide fire planners and incident managers with the location of known and likely habitat before fuel reduction, fire response or post-fire works.
  • Do not allow fire retardants, ash-laden runoff or sediment slugs to enter occupied streams.
  • Avoid changing groundwater recharge, drainage concentration or low-flow pathways in the local catchment.
  • Treat post-fire repair, roadworks and debris removal as high-risk activities requiring aquatic habitat assessment.

Threats: Feral animals, disease and genetic risk

Feral pigs and deer can trample, wallow and root stream margins, increasing erosion, turbidity, nutrient enrichment and sedimentation. Parasitic metacercarial cysts have been recorded in related mountain galaxias, but prevalence and effects in tapered galaxias are unknown.

The single small population is exposed to genetic decline, loss of genetic diversity and inbreeding. Preliminary genetic information indicates substantial loss of genetic diversity and high inbreeding.

  • Control feral pigs and deer where they damage stream banks or deliver sediment to the catchment.
  • Do not move fish, water, substrate or aquatic equipment between sites without approved disease and biosecurity controls.
  • Report unusual fish mortality, lesions, cysts or parasite signs to the relevant authorities and retain evidence only under approved protocols.

Survey methodology: 1. Confirm habitat and survey extent

The tapered galaxias is a small, non migratory freshwater fish known from the headwaters of Stoney Creek in West Gippsland, Victoria. Project surveys should focus on shallow, clear, cool, slow flowing forest streams with cobble riffles and glides, and should be led by appropriately authorised freshwater fish ecologists.

Review the project footprint, upstream and downstream drainage, access tracks, crossings and any areas that could deliver sediment, pollutants or altered flows to headwater habitat.

Inspect and map shallow riffles and glides with cobble, gravel, bedrock, undercut banks, timber debris and vegetation overhang, because these features are associated with tapered galaxias habitat.

Extend the assessment beyond the immediate work area where the project could affect surface water or groundwater supporting the stream.

Search the upper Thomson River catchment and connected headwater reaches where suitable habitat occurs, because additional subpopulations have not been excluded.

Known distribution: A single known subpopulation in approximately 12 km of the upper Stoney Creek reach, from upstream of Stoney No. 5 Track to 2.5 km downstream of Stoney No. 4 Track.

Typical habitat: A clear, cool, slow flowing creek about 0.5 to 1.5 m wide and 0.1 to 0.5 m deep.

Capture microhabitat: Mainly among cobble in shallow water about 0.15 to 0.20 m deep, in gently flowing riffles or glides.

Survey methodology: 2. Undertake targeted fish surveys

Use backpack electrofishing at representative riffles and glides, including cobble margins, shallow runs and areas around instream cover, where the method is permitted and can be undertaken safely by trained and authorised operators.

Use a consistent, recorded survey design across all suitable reaches, including the length surveyed, start and end points, water depth, flow, conductivity, water temperature, turbidity and habitat type.

Inspect areas near natural barriers and downstream reaches for introduced brown trout, because the known tapered galaxias population persists upstream of a waterfall where trout occur below the barrier.

Use validated environmental DNA methods only where the method is available and approved for this species, and treat a negative result as requiring interpretation against detection conditions and survey coverage.

Known density range: Reported densities range from 0.01 to 0.9 fish per square metre.

Species size: Usually 65 to 70 mm length to caudal fin, with a reported maximum of 84 mm and 6 g.

Survey effort specified in the supplied documents: No species specific number of sites, transect length, electrofishing passes, trap nights or survey nights is specified.

  • Do not rely on visual observation alone, because the species is small and occurs among cobble in shallow flowing water.
  • Record all native fish and introduced salmonids captured or detected, including their location and abundance.
  • Have an aquatic fauna specialist identify captured fish before release, and retain voucher material only where authorised and necessary.

Survey methodology: 3. Record habitat condition and threats

Map the full stream reach assessed and photograph representative riffles, glides, pools, banks, crossings, barriers and sediment deposits.

Record cobble cover, embedded sediment, bank disturbance, riparian shade, water depth, flow, water quality, barriers and signs of drying or recent fire impacts.

Inspect for brown trout and rainbow trout, including evidence of fish passage over or around barriers, because salmonid predation is the highest ranked threat to this species.

Record feral pig and deer activity, road and track sediment sources, forestry disturbance, fire impacts, drought stress and any works that could change water flow or water quality.

  • Treat any confirmed tapered galaxias record, suspected salmonid incursion or substantial habitat deterioration as a reportable project issue under the fauna management plan.
  • Use photographs, coordinates and a reach identifier for every positive detection and every recorded threat.

Survey methodology: Minimum effort and reporting

  • Obtain advice from the Victorian wildlife and fisheries authorities before finalising the survey design, because the supplied documents do not prescribe a minimum survey effort for this species.
  • Survey every suitable reach within the impact area and all connected habitat that could receive sediment, altered flows, pollutants or introduced fish from the works.
  • Repeat surveys when the first survey is inconclusive, habitat conditions are unsuitable, or works could affect a new part of the drainage network.
  • Submit confirmed records, negative survey results where relevant, salmonid detections, habitat mapping and photographs to the relevant Victorian wildlife or biodiversity records database and provide the records to the project regulator.
  • Report the survey dates, personnel and licences, equipment, electrofishing settings, effort, reach length, environmental conditions, detections, handling and release details, and any eDNA laboratory information.

Before habitat disturbance: Avoid and minimise

Avoiding disturbance to the occupied headwater reach is the safest protection measure. The species has one known subpopulation, a very small distribution and limited ability to recolonise habitat after local loss.

Critical habitat setting: Upper Stoney Creek headwaters at approximately 340 to 545 m above sea level.

Known occupied area: Approximately 12 km of stream reach, with the proposed assessment document reporting approximately 0.02 km2 of occupied habitat.

  • Avoid works in the known upper Stoney Creek reach and in adjoining drainage lines wherever a practicable alternative exists.
  • Retain shallow cobble riffles and glides, natural banks, undercut banks, woody debris, overhanging vegetation, riparian shade and the local catchment that maintains surface and groundwater inputs.
  • Keep machinery, stockpiles, spoil, fuels, concrete washout, sediment basins and refuelling areas outside the stream and its drainage lines.
  • Prevent changes to flow, water temperature, dissolved oxygen, turbidity, sediment load and streambed structure.
  • Maintain natural or approved artificial barriers that prevent salmonid movement, and do not create access or work conditions that could allow trout to enter upstream habitat.

Before habitat disturbance: Approvals and work planning

  • Assess the action under the EPBC Act before works begin, because the tapered galaxias is listed as Critically Endangered and significant impacts may require referral and approval.
  • Obtain all Victorian permits, authorisations and approvals for threatened fish, fish handling, electrofishing, waterway works, salvage and translocation before mobilising.
  • Prepare a species specific aquatic fauna management plan covering survey, exclusion, sediment and water quality controls, fish rescue, incident response, communication and reporting.
  • Schedule instream disturbance outside the suspected late winter to spring spawning period where practicable, and obtain advice from the relevant Victorian authority where timing cannot be avoided.
  • Stage works so that an unaffected, connected refuge reach remains available and so that the duration of isolation, dewatering or turbidity is as short as practicable.

Before habitat disturbance: Prepare the site

  • Complete a pre clearance aquatic fauna survey immediately before works, using the approved method and checking for tapered galaxias, other native fish and introduced salmonids.
  • Mark the approved work limits, no go stream sections, riparian protection zones, access routes, refuelling areas, spoil areas and emergency fish refuge areas before machinery enters the site.
  • Install sediment, erosion and pollution controls before clearing or earthworks, and inspect them after rainfall and before each shift.
  • Use exclusion fencing or equivalent controls where they can prevent machinery, people, stock or materials entering retained stream habitat without blocking required fish passage.
  • Brief all operators on the species appearance, habitat, stop work triggers, spill response, fish handling limits and the location of retained habitat.

During habitat disturbance: Daily controls and machinery coordination

Works must be controlled as an aquatic habitat operation, not treated as ordinary terrestrial clearing. A fauna spotter catcher should work with the aquatic ecologist, supervisor and machinery operator under the approved management plan.

  • Hold a daily pre start inspection of stream condition, weather, flow, turbidity, sediment controls, exclusion fencing, barriers and approved work limits.
  • Keep machinery out of the channel unless the approval specifically allows entry and the aquatic ecologist has cleared the method.
  • Use the smallest practicable machinery and work from stable, designated access points to avoid crushing cobble, banks, woody debris and shallow riffles.
  • Stop or modify works if turbidity, sediment movement, fuel, concrete, chemical or other pollution enters the stream or if flows, barriers or water levels change unexpectedly.
  • Keep a competent fauna spotter or aquatic ecologist in communication with the operator during in channel work, dewatering, crossings, bank disturbance and removal of instream material.

During habitat disturbance: Habitat and fish handling

  • Treat cobble, gravel, bedrock, undercut banks, timber debris, overhanging vegetation and shallow riffles as potential fish habitat and move them only under the approved method.
  • Do not capture, handle, identify, hold, transport or release tapered galaxias unless the person is authorised under the relevant Victorian approval and trained in native fish handling.
  • If fish rescue is approved, isolate and inspect the affected reach progressively, use an authorised aquatic fish rescuer, maintain suitable water quality and release fish into nearby retained habitat selected in the management plan.
  • Do not relocate fish to another creek or establish a new population as an on site response, because translocation requires separate planning, approvals, predator exclusion and biosecurity.
  • Treat hollow trees, terrestrial logs, rocks and burrows as project fauna features only where they affect the waterway or riparian buffer; for this species, priority features are the streambed, flow, banks, riparian shade and water quality.

During habitat disturbance: If the species or a threat is found

  • Stop the relevant activity immediately if a tapered galaxias is found, if a fish cannot be identified safely, if salmonids are detected upstream of the known barrier, or if the work causes unexpected habitat damage.
  • Protect the location from machinery, people, sediment and altered flows while the aquatic ecologist and project environmental officer determine the approved response.
  • Notify the project manager, environmental officer and relevant Victorian authority in accordance with the approval and fauna management plan.
  • Send injured fish to an authorised aquatic wildlife carer, veterinarian or fish health professional as directed by the approval, and record the chain of custody.
  • Record the date, time, coordinates, reach, work activity, species identification, number and life stage if known, handling, release or injury outcome, photographs, personnel and corrective actions.

After habitat disturbance: Close out and inspect

Post work checks must confirm that the stream remains suitable for a small, shallow water galaxiid and that no new pathway has been created for trout or sediment movement.

  • Remove temporary machinery, crossings, pumps, pipes, spoil, waste, sediment controls and other materials that could obstruct flow or enter the stream, unless they are approved permanent structures.
  • Inspect the full affected reach and downstream receiving habitat for dead or stranded fish, sediment deposits, bank collapse, damaged cobble riffles, altered flow, pollution and damaged barriers.
  • Complete a post clearance aquatic fauna check where fish were rescued, water was diverted, habitat was dewatered, the channel was disturbed or an incident occurred.
  • Repair or escalate any failed erosion, sediment, pollution or fish exclusion control before demobilisation.

After habitat disturbance: Monitoring and reporting

  • Monitor water quality, flow, streambed condition, riparian cover, barriers, salmonid presence and habitat recovery at the frequency required by the approval and fauna management plan.
  • Repeat fish surveys or eDNA sampling using the same recorded reach and method where the project may have affected occupancy, abundance, recruitment or predator exclusion.
  • Compare post work results with pre work photographs, habitat measurements and fish records, rather than relying only on whether a fish was seen.
  • Report all incidents, corrective actions, fish handling, survey results and unexpected impacts to the regulator, approval holder and relevant Victorian wildlife database.

After habitat disturbance: Ongoing controls and offsets

  • Maintain riparian exclusion zones, sediment controls, access controls and barrier protection until the site is stable and the environmental officer signs them off.
  • Continue monitoring if the works changed flow, water quality, streambed structure, riparian vegetation or access to the catchment.
  • Apply any approved offset, conservation payment or compensatory action only in accordance with the EPBC Act decision, Victorian requirements and the approved management plan.
  • Do not treat an offset as a substitute for avoiding or minimising impacts to the known subpopulation.

Rehabilitation actions: Restore stream and riparian habitat

Rehabilitation should restore cool, clear, shallow flowing headwater habitat and reduce the chance of salmonid invasion. It should be designed with the Victorian aquatic ecologist, land manager and Traditional Owners where relevant.

Target stream setting: Clear, cool, slow flowing headwater creek, commonly 0.5 to 1.5 m wide and 0.1 to 0.5 m deep.

Target fish microhabitat: Shallow riffles and glides about 0.15 to 0.20 m deep with cobble cover.

  • Reinstate stable natural streambed material and retain or replace cobble, gravel and bedrock conditions needed for shallow riffles and glides.
  • Repair banks and drainage lines with locally appropriate native riparian vegetation that provides shade, bank stability, overhanging cover and protection from sediment delivery.
  • Remove or redesign road and track drainage, crossings and exposed soil that discharge sediment into the stream.
  • Retain suitable timber debris, undercut bank structure and rock cover where these can be placed without obstructing fish passage or causing erosion.
  • Do not install terrestrial nest boxes or artificial hollows as a substitute for aquatic habitat restoration, because these features are not identified as tapered galaxias habitat.

Rehabilitation actions: Control predators, weeds and fire impacts

  • Inspect and maintain natural or artificial barriers that exclude brown trout and rainbow trout, including after floods and high flow events.
  • Remove introduced salmonids using authorised methods where they are detected in tapered galaxias habitat, and prevent stocking, illegal release and access that could assist fish movement.
  • Control feral pigs and deer where they trample banks, wallow, root soil or increase sediment and turbidity.
  • Manage weeds and revegetation so that stream shade, bank stability and native riparian cover are restored without blocking the channel.
  • Prepare fire prevention, response and recovery measures that protect the stream from high water temperatures, ash, sediment, toxic suppression products and post fire erosion.

Rehabilitation actions: Monitor success

  • Monitor survival and establishment of riparian plants, bank stability, sediment deposition, cobble availability, riffle and glide condition, water quality and flow.
  • Monitor tapered galaxias abundance and size structure, and inspect for evidence of recruitment, using a consistent authorised fish survey method.
  • Monitor salmonid presence and abundance and inspect barriers annually or after high flow events.
  • Investigate any loss of the first four to five age classes as a possible indication that a predator is present, as specified in the conservation advice.
  • Set success measures in the approved plan, including stable or improving habitat condition, no salmonid incursion, functioning sediment controls and documented persistence or recovery of the fish population.

Sources