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Stocky Galaxias (Galaxias tantangara)

The Stocky Galaxias is a small, non-migratory freshwater fish restricted to cold, clear, fast-flowing alpine creeks in the Snowy Mountains of New South Wales. It is listed as Critically Endangered under the EPBC Act, so works that disturb headwater streams, riparian vegetation, stream beds or water quality require strong controls and species-specific advice.

Conservation status

Commonwealth, EPBC Act 1999: Critically endangered.

Breeding season

The pattern below describes the known annual cycle for Stocky Galaxias. Timing is based on observations from its alpine New South Wales habitat and may vary between streams and years.

The species remains present year-round in its resident alpine streams. Project timing does not remove the need for aquatic biosecurity, sediment control, riparian protection and specialist advice.

  • Breeding: Males mature earlier in the year, females mature by about October, and spawning occurs mainly in mid-November. Eggs are attached beneath cobbles at riffle heads.
  • Young: Larvae have been detected in December. Eggs are reported to hatch after about 35 to 40 days, so egg and larval development extends from late spring into summer.
  • Movement and home range: The species is non-migratory and has a very limited home range, up to 5.5 m for 50% of fish and 16 m for 75% of fish. Winter snow cover is common in its habitat.
  • Highest clearing risk: Clearing, stream access and instream disturbance are most likely to harm the species from October to December, when reproductive development, spawning, eggs and newly developing larvae may be present. Sediment and flow impacts can affect habitat at any time.

Identification

Stocky Galaxias is a small, stocky fish with a blunt head, rounded snout and dark spotting across the head and body. Identification is most reliable in clear, shallow streams where the whole fish can be examined.

The back and upper sides are dark olive-brown to brown, becoming lighter brown to cream underneath. Dark brown to almost black spots and flecks vary in size and may form irregular bands or blotches. The spots extend over the top of the head, cheeks and jaws. The eyes are described as gold, the gill covers are translucent and the fins are translucent with a dusky grey colour. The tail is truncate or slightly forked and is about the same length as, or slightly longer than, the caudal peduncle.

Typical length: 65 to 90 mm length to caudal fork

Commonly observed length: 75 to 85 mm

Maximum recorded length: 103 to 113 mm length to caudal fork

Maximum recorded weight: 13 to 14.3 g

Identification: Separating similar galaxias

Stocky Galaxias may be confused with Mountain Galaxias and other small galaxids. The extension of dark spotting onto the top of the head, cheeks and jaws is a useful feature separating it from Mountain Galaxias. The species also has a blunt, moderately deep and slightly bulbous head, a wide mouth reaching to below the middle of the eyes, and an anal fin that is longer than the dorsal fin.

  • Do not rely on colour alone, because colour and blotch pattern may vary between individuals and stream conditions.
  • Seek an appropriately qualified fish ecologist where identification is uncertain, particularly because Mountain Galaxias occurs in the same stream as Stocky Galaxias at Sallys Flat Creek.

Identification: Field detection

There are no reliable terrestrial field signs such as tracks, scats, calls, nests, sloughs or eyeshine. Detection depends on finding live fish in suitable cold, clear streams and confirming the diagnostic body pattern and fin characters. The species is most likely to be encountered in shallow riffles, glides and pools in the small headwater creeks where it is known to occur.

  • Treat any small galaxias found in or near the known range as potentially significant until identified by a suitably experienced person.
  • Avoid handling, relocating or retaining fish during project surveys unless the work is authorised and undertaken under the relevant fish handling and biosecurity procedures.

Distribution: National range

The Stocky Galaxias is known only from a very small area of the Snowy Mountains in New South Wales. No records are reported from other Australian states or territories.

The species is known only from New South Wales, in the upper Murrumbidgee catchment and nearby headwaters of the Goodradigbee River. Known sites are within or associated with Kosciuszko National Park and occur at about 1,330 to 1,463 m above sea level.

State range: New South Wales only

Bioregional setting: Snowy Mountains alpine headwaters, including the upper Murrumbidgee and nearby Goodradigbee catchment headwaters

Known elevation: About 1,330 to 1,463 m above sea level

  • Known streams are Tantangara Creek, upstream of Tantangara Reservoir, and Sallys Flat Creek, above a waterfall in the Goodradigbee River headwaters.
  • The species is not known from outside New South Wales.

Distribution: Known populations and strongholds

Until 2021, Stocky Galaxias was known from about 3 km of Tantangara Creek. A second occurrence was then found in about 2.5 km of Sallys Flat Creek, above a waterfall that provides protection from trout. A refuge population has also been rehabilitated at Eucumbene Borrows within Kosciuszko National Park.

Tantangara Creek occurrence: About 3 km of stream historically known

Sallys Flat Creek occurrence: About 2.5 km of stream above a waterfall

Known refuge site: Eucumbene Borrows, within Kosciuszko National Park

  • Tantangara Creek is the principal known stronghold described in the available material.
  • Sallys Flat Creek is a separate known occurrence and supports Stocky Galaxias with Mountain Galaxias, without evidence of hybridisation.
  • Waterfalls and other substantial barriers are important because they prevent trout incursions.

Distribution: Population size and trend

The total wild population size is not provided. The species has an extremely restricted distribution and has been described as a single small wild population in some conservation planning material, although more recent accounts also report Sallys Flat Creek and the Eucumbene Borrows refuge. Population monitoring and genetic assessment are needed to clarify the number and condition of populations.

Estimated total population: Unknown

2019 to 2020 fire rescue: 142 fish rescued from Tantangara Creek

Trend: Declining or at high risk of decline; a quantitative population trend is not provided

  • A total of 142 Stocky Galaxias were rescued from Tantangara Creek during the 2019 to 2020 fires; this is a rescue count, not an estimate of total population size.
  • The species is considered threatened by its very limited distribution and exposure to stochastic events such as fire, drought and predator invasion.

Habitat: Stream and catchment setting

Stocky Galaxias occupies very small, cold, clear and fast-flowing sub-alpine creeks. It depends on clean, well-oxygenated water, intact instream structure and barriers that exclude introduced trout.

Known habitat consists of narrow alpine creeks averaging about 0.5 to 0.8 m wide and 0.1 to 0.3 m deep. Streams may flow through open eucalypt forest with low shrubs and tussock grass, or through open tussock grassland. Snow cover is common during winter.

Average stream width: About 0.5 to 0.8 m

Average stream depth: About 0.1 to 0.3 m

Known elevation: About 1,330 to 1,463 m above sea level

Water conditions: Cold, clear, flowing and well oxygenated

  • Expect suitable habitat in cold headwater creeks rather than broad rivers, reservoirs or warm lowland streams.
  • The species is associated with riffles, glides and connected shallow pools.
  • Water should be clear, flowing and well oxygenated, with low sediment loads.

Habitat: Key habitat structure

Instream cover includes bedrock, boulders, cobbles, rocks, undercut banks, aquatic vegetation and overhanging vegetation. At Tantangara Creek, surrounding vegetation includes eucalypts, low shrubs and tussock grass. At Sallys Flat Creek, open tussock grassland is prominent.

  • Retain stream banks, overhanging vegetation and aquatic plants.
  • Prevent sediment from entering riffles, pools and cobble beds.
  • Maintain natural flow, water temperature, dissolved oxygen and connectivity between pools.
  • Protect waterfalls and other barriers that exclude trout and other introduced fish.

Foraging habitat: Diet and feeding areas

The diet of Stocky Galaxias has not been directly described, but it is expected to resemble other members of the Mountain Galaxias complex. Feeding habitat is therefore likely to be concentrated in clean flowing water with access to aquatic invertebrates and riparian insect fall.

The likely diet consists of drifting and benthic aquatic invertebrates. Insect fall from fringing riparian vegetation may also contribute, as it does for the closely related Mountain Galaxias. The fish is expected to feed within its small home range rather than making long movements between feeding areas.

Likely prey: Drifting and benthic aquatic invertebrates, with possible input from insects falling from riparian vegetation

Home range: Up to 5.5 m for 50% of fish and 16 m for 75% of fish

Foraging range: Very limited; the species is non-migratory

  • Retain riparian vegetation that supplies terrestrial insects to the stream.
  • Protect riffles, glides, pools, cobble beds and undercut margins that support aquatic invertebrates.
  • Prevent ash, fine sediment, pollutants and excessive algal or organic loading from reducing invertebrate habitat and water quality.

Breeding habitat: Breeding biology

Breeding occurs in cold, flowing headwater habitat, with eggs attached beneath small cobbles at the head of riffles. Breeding sites are sensitive to sedimentation, altered flow, poor oxygen levels and direct disturbance of the stream bed.

Spawning has been observed in mid-November when mean daily water temperature was about 10 degrees Celsius. Males mature earlier than females, and females may use more than one spawning site. The only spawning site described was beneath a small cobble at the head of a riffle, where an egg mass of about 50 eggs was attached.

Spawning season: Mainly mid-November, with reproductive development beginning earlier in the year

Spawning temperature: Mean daily water temperature about 10 degrees Celsius at the observed spawning event

Egg production: About 210 eggs in a 76 mm fish to 810 eggs in a 100 mm fish

Observed egg mass: About 50 eggs attached beneath a small cobble

Egg diameter: 1.7 to 2.2 mm before spawning

Hatching or incubation: About 35 to 40 days

Larvae: Detected in December; newly hatched larvae are about 9.4 to 10.1 mm long

Age at maturity: Males may mature in their second year; females in their second or third year

Lifespan: Not provided

  • Avoid disturbing cobbles, riffle heads and shallow spawning habitat from late October through December.
  • Keep fine sediment, ash and construction runoff out of riffles during the breeding and egg development period.
  • Maintain cold, clear, flowing and well-oxygenated water around spawning habitat.

Breeding habitat: Breeding habitat features

The known spawning microhabitat is a cobble at the head of a riffle in a small, shallow, fast-flowing creek. Flow across the egg surface is likely to help keep eggs oxygenated and free of deposited sediment, so even small increases in sediment input can reduce breeding habitat quality.

  • Retain natural riffle structure and stable cobbles.
  • Prevent machinery, vehicle crossings and temporary access works from disturbing the stream bed.
  • Use effective sediment and runoff controls before ground disturbance begins, especially upstream of known or potential breeding habitat.

Sheltering habitat: Instream refuge

Stocky Galaxias uses small-stream cover rather than terrestrial shelters. Important refuges include rock and cobble structure, undercut banks, aquatic vegetation and overhanging riparian vegetation, with waterfalls providing refuge from trout.

Recorded cover includes rocks, undercut banks and overhanging vegetation at Tantangara Creek, and aquatic vegetation and undercuts at Sallys Flat Creek. The species also occurs upstream of substantial waterfalls that restrict access by introduced trout.

Known refuge structures: Rock, cobble, bedrock, boulders, undercut banks, aquatic vegetation and overhanging vegetation

Natural predator barrier: Substantial waterfalls that exclude trout

Stream scale: About 0.5 to 0.8 m average width and 0.1 to 0.3 m average depth

  • Retain undercut banks, cobbles, boulders, bedrock, aquatic plants and overhanging vegetation.
  • Do not infill, armour, straighten or otherwise simplify small pools, riffles or stream margins without species-specific approval.
  • Keep temporary crossings and waterway access points away from known habitat where possible.

Sheltering habitat: Fire and drought refuges

The species has a very restricted range, so unburnt stream sections and reaches with reliable flow may be important during fire and drought. Fire can increase ash and sediment inputs, while drought can dry streams and remove available refuge habitat.

  • Protect unburnt reaches and any persistent pools during fire response and post-fire works.
  • Avoid concentrating runoff into occupied streams after vegetation clearing, roadworks or fire-related ground disturbance.
  • Treat any emergency fish rescue or relocation as specialist conservation work requiring authorisation and biosecurity controls.

Threats: Introduced fish and biosecurity

The main risks are introduced predatory fish, the species' extremely small range, fire and drought, sedimentation, riparian damage and changes to stream flow or water quality. Construction and infrastructure projects can increase these risks through stream crossings, clearing, runoff, barriers and accidental fish transfers.

Rainbow Trout and Brown Trout are the major threat because they prey on and compete with native galaxiids. The species is now largely confined to reaches above barriers that exclude trout. The proposed or potential movement of non-native Climbing Galaxias through the Snowy 2.0 system is also identified as a risk, because waterfalls would not necessarily exclude it. Oriental Weatherloach may threaten eggs, and illegal live-bait use could spread the species.

  • Do not transfer water, fish, aquatic plants, sediment or equipment between catchments without approved aquatic biosecurity procedures.
  • Prevent trout access to occupied streams and maintain the integrity of natural or constructed barriers.
  • Treat all project waterway equipment as potentially contaminated until cleaned, disinfected and dried under the relevant protocol.
  • Report suspected introduced fish, fish kills or barrier damage promptly to the relevant authority.

Threats: Fire, drought and climate

Bushfire can heat small streams and deliver ash and sediment during subsequent rainfall. Severe drought can dry streams, increase water temperature and reduce refuge habitat. Climate change is expected to increase the frequency or severity of drought, fire, storms and floods and alter snowmelt and stream flow patterns.

  • Keep post-fire runoff, ash and eroded soil out of occupied streams.
  • Protect riparian shading and ground cover to reduce heating, erosion and sediment delivery.
  • Plan water extraction, dewatering and instream works around low-flow and drought conditions, when available habitat is reduced.
  • Retain and protect unburnt or hydrologically persistent stream sections.

Threats: Clearing, earthworks and hydrology

Loss of riparian vegetation, overgrazing, feral horse damage and sedimentation can alter stream width, depth, substrate, shading and organic inputs. Road crossings, construction access, trenching, spoil placement, dewatering and altered drainage can create the same pressures. The species' short occupied reaches mean that a local impact may affect a substantial part of a population.

  • Before clearing or construction, survey all potentially connected cold headwater streams within the project area and downstream receiving reaches using appropriately qualified freshwater fish specialists.
  • Maintain riparian vegetation and avoid placing spoil, sediment controls, fuels or concrete washout where runoff can reach a stream.
  • Design crossings and drainage so they do not create trout access, block fish habitat or cause scour and fine sediment deposition.
  • Do not pump from, dewater or divert occupied streams without project-specific approval and a fish rescue plan.
  • Inspect stream barriers after floods and major works, because barrier failure may allow trout or other invasive fish to move upstream.

Threats: Development and infrastructure risk

The Snowy 2.0 pumped hydro scheme is specifically identified as having potential to introduce non-native Galaxias between catchments. More generally, any project that connects waterways, moves aquatic materials or changes flow paths can increase invasion and disease risks.

  • Keep catchments and water supply systems separate unless an approved design and biosecurity plan prevents fish, eggs, pathogens and contaminated water from moving between them.
  • Use isolated, secure water treatment and discharge systems for construction compounds and hatchery or rescue facilities.
  • Include Stocky Galaxias in environmental incident response plans for pollution, fish kills, wildfire, drought, barrier failure and uncontrolled dewatering.

Survey methodology: 1. Define the aquatic survey area

Stocky Galaxias is a very restricted, non-migratory freshwater fish of small, cold, clear and fast-flowing alpine creeks. No species-specific survey guideline is provided in the supplied documents, so survey design should be prepared by a qualified freshwater fish ecologist and agreed with the relevant state agency before works begin.

Map all small streams, headwaters, riffles, glides, pools, waterfalls and upstream refuge areas within and downstream of the proposed works.

Extend the assessment beyond the construction footprint where sediment, altered flows, barriers or introduced fish could affect habitat.

Inspect tributaries and nearby headwater streams because the species is known from only short sections of Tantangara Creek and Sallys Flat Creek, and a refuge population has been established at Eucumbene Borrows.

Known stream occupancy: About 3 km of Tantangara Creek and about 2.5 km of Sallys Flat Creek, with records from the upper Murrumbidgee catchment

Typical habitat: Small creeks averaging about 0.5 to 0.8 m wide and 0.1 to 0.3 m deep, with cold, clear, fast-flowing water

Known elevation: About 1,330 to 1,463 m above sea level

Survey methodology: 2. Backpack electrofishing and netting

Use appropriately authorised backpack electrofishing, supported by seine or hand-net sampling where safe and suitable, as the primary field method for this freshwater fish.

Survey riffles, glides, shallow pools, undercut banks, instream cover and areas upstream of barriers such as waterfalls.

Use an experienced operator, an approved animal ethics and fish handling procedure, and the lowest effective electrical settings for the water conductivity and fish size.

Record effort, including the length of stream surveyed, electrofishing time, number of passes, netting effort, water conditions and all fish captured or observed.

Release Stocky Galaxias at the capture location unless an approved rescue, translocation or captive management action is in place.

Survey methodology: 3. Habitat and barrier inspection

Complete a detailed habitat assessment even where fish are not detected, because the species is patchily distributed and may occupy only short sections of suitable headwater stream.

Record substrate, flow, depth, water temperature, dissolved oxygen, turbidity, riparian cover, overhanging vegetation, undercut banks, rocks and aquatic vegetation.

Map waterfalls, culverts, crossings and other barriers that may exclude trout or affect movement between occupied and retained habitat.

Inspect for trout and other introduced fish in the same catchment, including downstream of known Stocky Galaxias habitat.

Important cover: Rock, undercut banks, overhanging vegetation and aquatic vegetation

Spawning habitat: The only recorded spawning site was beneath a small cobble at the head of a riffle

Movement: The species is non-migratory and has a very limited home range, up to 5.5 m for 50% of fish and 16 m for 75% of fish

Survey methodology: 4. Timing and repeat surveys

Survey during suitable low to moderate flow conditions when water is clear enough for safe sampling and fish detection, and avoid sampling during high flows, flood conditions or immediately after sediment-laden runoff.

Include late October to mid-November surveys where possible, because spawning occurs during this period and adults, eggs or larvae may be present near riffles.

Use repeat visits when a single survey could be affected by drought, fire runoff, poor water clarity or low flow.

Treat a non-detection as inconclusive unless the survey covered suitable habitat with documented, adequate effort agreed by the project ecologist and relevant agency.

Spawning period: Mid-November, with spawning observations in late November and larvae detected in December

Water temperature associated with spawning: About 10 degrees Celsius mean daily water temperature

Survey limitation: The species has a very limited distribution and may occur in short, isolated stream sections

Survey methodology: Minimum effort and reporting

  • Prepare a site-specific survey plan before access, including stream lengths, survey methods, repeat visits, water conditions, fish welfare controls and stop-work criteria.
  • Have a qualified freshwater fish ecologist set the number of passes, survey length and repeat visits because no species-specific effort guideline is supplied in the available documents.
  • Record precise locations, date, time, observers, equipment, effort, water quality, habitat condition, photographs and all captures or non-detections.
  • Report any Stocky Galaxias record, suspected record, mortality or emergency rescue promptly to the relevant state wildlife or fisheries authority.
  • Submit verified occurrence records to the relevant state wildlife database and the national biodiversity records system where required by the approval or permit.
  • Report introduced trout, Oriental weatherloach, suspected Climbing Galaxias, fish disease and barriers that could affect the species through the relevant state reporting pathway.
  • Retain raw field sheets, photographs, spatial data and chain-of-custody information with the project environmental records.

Before habitat disturbance: Avoid and minimise

Treat any suitable alpine headwater creek as potentially important habitat until a competent survey shows otherwise. The species has an extremely limited distribution, is listed as Critically Endangered under the EPBC Act, and can be affected by a single fire, sediment event, drought or predator incursion.

  • Avoid direct disturbance to small cold, clear and fast-flowing creeks, especially riffles, glides, shallow pools, undercut banks, cobble beds and areas upstream of trout-excluding waterfalls.
  • Retain riparian vegetation, overhanging vegetation, aquatic plants, undercut banks, rocks, cobbles and stable stream margins.
  • Keep construction plant, spoil, fuels, concrete washout, chemicals and stockpiles out of the drainage line and its contributing catchment.
  • Maintain natural stream flow, water temperature, dissolved oxygen, substrate and shading during and after the works.
  • Retain connected upstream and downstream habitat and do not remove, lower or bypass barriers that currently exclude trout or other introduced fish.
  • Do not create new access crossings or alter existing crossings without assessing sediment, fish passage and predator-incursion risks.

Before habitat disturbance: Approvals and project planning

National status: Critically Endangered under the EPBC Act

NSW status: Critically Endangered according to NSW Department of Primary Industries

Known protective feature: All known populations are currently protected by barriers that prevent trout incursions

  • Check whether the action requires referral or approval under the EPBC Act because Stocky Galaxias is nationally listed as Critically Endangered.
  • Check state threatened species, fisheries, national park, waterway, fish collection, translocation and animal ethics requirements before survey, capture, relocation or construction.
  • Engage the relevant state fisheries or conservation agency early where works may affect known or potential habitat.
  • Prepare a species-specific fauna management plan covering survey, exclusion, water quality, fish rescue, biosecurity, emergency extraction, incident reporting and rehabilitation.
  • Stage works to keep occupied or potential habitat isolated from active work areas and to allow fish rescue before dewatering or in-stream works.
  • Avoid works during late October to December where practicable, when spawning and larvae may be present, unless the agency-approved method specifically manages that risk.

Before habitat disturbance: Site preparation

  • Complete the approved pre-clearance aquatic fish survey before vegetation removal, earthworks, dewatering, access construction or disturbance of the bed and banks.
  • Mark no-go areas around occupied or suitable stream habitat, riparian vegetation, riffles, undercut banks, cobble beds, barriers and retained refuge reaches.
  • Install exclusion fencing or other clearly visible controls where these can prevent plant, vehicles, people, sediment and materials entering the stream.
  • Confirm that erosion and sediment controls are installed, maintained and able to contain runoff during rainfall.
  • Inspect machinery, pumps, hoses, nets, buckets and footwear and disinfect them between waterways to prevent transfer of fish, eggs, pathogens and aquatic weeds.
  • Prepare clean, aerated holding containers and approved transport equipment before any authorised capture or rescue.

During habitat disturbance: Daily controls and machinery coordination

The fauna spotter catcher must work as part of the construction team, not as a substitute for aquatic impact controls. Stop the activity before a fish, sudden water-quality change or uncontrolled sediment movement causes harm.

  • Hold a daily pre-start briefing with the site supervisor, machinery operators, aquatic ecologist and fauna spotter catcher.
  • Walk the exclusion boundary and inspect fencing, sediment controls, stream flow, water clarity, fuel storage, crossings, pumps and discharge points before work starts.
  • Keep machinery outside the stream and riparian exclusion area unless the approved method specifically permits entry.
  • Use a spotter to maintain direct communication with operators during any work near water, banks, crossings or retained habitat.
  • Stop work during intense rainfall, rising flows, uncontrolled runoff, loss of sediment containment, fuel or chemical spills, or any change that could carry ash, soil or concrete into the creek.
  • Do not pump, divert or discharge water into Stocky Galaxias habitat until the water quality, flow rate and discharge method have been checked and approved.

During habitat disturbance: Fish rescue and handling

  • Use only personnel authorised under the relevant permit and approved fauna management plan to capture, handle, transport or release Stocky Galaxias.
  • Before dewatering or isolating a work area, conduct an approved fish rescue using qualified freshwater fish personnel and suitable electrofishing or netting methods.
  • Keep captured fish in clean, temperature-appropriate, oxygenated water and minimise handling, crowding, noise, transport time and changes in water temperature.
  • Release fish into nearby retained habitat only where the release location is approved, free of introduced predators and suitable for the species.
  • Do not relocate fish across a catchment, barrier or project boundary without written approval and a documented translocation plan.
  • If a fish is injured, stressed, dead or suspected to be Stocky Galaxias, stop handling beyond what is needed for welfare, photograph and record it, and contact the responsible state agency and an approved aquatic wildlife veterinarian or wildlife carer.
  • Do not release any captured fish if disease, contamination or an introduced species is suspected until the authorised aquatic ecologist gives direction.

During habitat disturbance: Habitat features and stop-work triggers

Spawning substrate: The recorded egg mass was attached to the underside of a small cobble at the head of a riffle

Downstream sediment risk: Post-fire sedimentation can affect waterways 50 to 80 km downstream of burnt areas

Main introduced predator threat: Rainbow Trout and Brown Trout

  • Protect riffles, cobbles, bedrock, boulders, undercut banks, overhanging vegetation and aquatic plants from machinery, sediment deposition and unnecessary removal.
  • Treat an egg mass beneath a cobble, larvae, a live Stocky Galaxias, a dead fish, trout, Oriental weatherloach or suspected Climbing Galaxias as an immediate environmental incident.
  • Stop the affected activity if a Stocky Galaxias is found outside the approved impact area, if fish are stranded, or if sediment, ash, fuel or other contaminants enter the water.
  • Stop work if a barrier protecting habitat is damaged, bypassed or made passable to trout or other introduced fish.
  • Prevent sediment from smothering stream substrate because post-fire sediment and ash can alter water chemistry, riparian shading and organic inputs, and can affect waterways well downstream of the burnt area.
  • Notify the project environmental officer and relevant agency before restarting work after a stop-work trigger.

During habitat disturbance: Records and incident reporting

  • Record the date, time, exact location, activity, personnel, machinery, weather, flow, water quality, fish observations, captures, mortalities, relocations and control failures each day.
  • Photograph fish, habitat damage, sediment movement, barriers, discharge points and any incident without delaying welfare actions.
  • Record the identification method and retain voucher photographs or other evidence for any suspected Stocky Galaxias record.
  • Report breaches, injured or dead fish, uncontrolled discharges, introduced predators and failed exclusion controls under the approval and fauna management plan.
  • Update the site risk assessment after each incident and revise the work method before recommencing.

After habitat disturbance: Post-clearance and reinstatement checks

Completion of construction does not end the risk. Check the retained creek and downstream habitat after works, during the first rainfall events and through the agreed monitoring period.

  • Inspect the full work area, stream bed, banks, riparian zone, crossings, culverts, discharge points and downstream reach after clearance and before demobilisation.
  • Confirm that no fish, eggs, larvae, pools, riffles, undercut banks, cobbles or other retained habitat features were stranded, buried, blocked or removed.
  • Remove temporary pumps, hoses, silt fences, access pads, spoil, waste and other materials that could obstruct flow or provide a pathway for predator entry.
  • Check that stream flow, bank stability, water clarity, substrate, shading and instream cover are consistent with the approved design.
  • Keep exclusion fencing and sediment controls in place until exposed soil is stabilised and the environmental officer confirms that removal will not increase risk.

After habitat disturbance: Monitoring and adaptive management

  • Monitor occupied and retained habitat using the same methods, locations and effort recorded during baseline surveys so changes can be compared.
  • Include checks after substantial rainfall, high-flow events, accidental discharges, fire, drought or any damage to a trout-excluding barrier.
  • Track fish detections, water temperature, dissolved oxygen, turbidity, flow, substrate condition, riparian cover, sediment deposition and introduced fish observations.
  • Increase survey or control effort if fish abundance declines, habitat is smothered, water quality changes, or trout or other invasive fish are detected.
  • Escalate unexpected impacts to the approval authority and relevant state fisheries agency rather than waiting for the scheduled monitoring report.

After habitat disturbance: Reporting and offsets

  • Submit completion, incident, rescue, mortality, monitoring and rehabilitation reports required by the EPBC approval, state permit and fauna management plan.
  • Provide verified species records to the relevant state wildlife database and national biodiversity records system where required.
  • Document whether the action avoided direct impact, retained habitat, maintained barriers, controlled sediment and achieved the approved rehabilitation outcomes.
  • Apply any approved offset, compensatory habitat protection or conservation payment only in accordance with the EPBC decision, state approval and agency direction.
  • Do not treat an offset as a substitute for avoiding disturbance to occupied habitat or preventing impacts during construction.

Rehabilitation actions: Stream and riparian restoration

Rehabilitation should recreate the cold, clear, shaded and structurally complex headwater creek conditions used by Stocky Galaxias. Focus first on preventing sediment and predator entry, then restore riparian cover, stream structure and connected refuge habitat.

Typical habitat setting: Open eucalypt forest, low shrubs and tussock grass, or open tussock grassland

Typical substrate: Bedrock, boulder and cobble with smaller amounts of pebble, gravel and silt

Important cover: Undercut banks, overhanging vegetation, rocks and aquatic vegetation

  • Stabilise disturbed banks and drainage paths with locally appropriate native alpine and riparian species selected by the land manager and relevant agency.
  • Restore overhanging vegetation, low shrubs, tussock cover and eucalypt woodland structure where those communities occur around the creek.
  • Reinstate stable bedrock, boulders, cobbles, gravel and small areas of silt in a way that maintains riffles, glides, shallow pools and undercut margins.
  • Replace removed instream cover only under an approved aquatic habitat design, and do not place loose material where it could move downstream or block fish habitat.
  • Prevent stock, feral horses, vehicles and pest animals from damaging banks, crossings, riparian vegetation or stream substrate.
  • Control weeds and prevent soil exposure from delivering sediment to the creek.

Rehabilitation actions: Barriers, predators and biosecurity

  • Retain and protect waterfalls or other approved barriers that currently prevent trout incursions.
  • Do not build a crossing, culvert, channel or outlet that allows Rainbow Trout, Brown Trout or another introduced fish to reach Stocky Galaxias habitat.
  • Inspect retained barriers after floods, major rainfall and construction because scour or altered flow may create a new predator pathway.
  • Control trout where authorised and report any trout, Oriental weatherloach or suspected Climbing Galaxias immediately to the relevant state agency.
  • Keep rehabilitated habitat and all equipment free of introduced fish, disease, pathogens and aquatic weeds through approved cleaning and quarantine procedures.

Rehabilitation actions: Fire, drought and extreme weather planning

Thermal tolerance information: The mountain galaxias complex has an anticipated upper thermal tolerance of about 33 degrees Celsius, with tolerance reduced by low dissolved oxygen and ash or sediment exposure

Emergency response example: 142 Stocky Galaxias were rescued from Tantangara Creek as the catchment began to burn in the 2019 to 2020 fires

  • Maintain riparian shade and stable banks to reduce exposure to high water temperatures and sediment delivery during drought, storms and fire-related runoff.
  • Prepare post-fire protection measures for occupied and restored reaches, including rapid inspection, sediment containment and assessment of ash and runoff risks before rainfall where practicable.
  • Use emergency extraction or captive management only under an agency-approved risk assessment when fire, drought, pollution or another event threatens fish survival.
  • Do not assume that a restored reach is safe for release until water quality, flow, predator exclusion and habitat condition have been checked.

Rehabilitation actions: Monitoring and success measures

  • Monitor restored reaches for fish presence, habitat condition, water temperature, dissolved oxygen, turbidity, flow, sediment deposition, riparian cover and barrier integrity.
  • Use baseline and reference reaches where available, and repeat the same survey methods and effort so trends can be assessed.
  • Set success measures that include stable riffles and pools, retained or recovered instream cover, functioning riparian vegetation, no uncontrolled sediment input and no predator incursion.
  • Record whether Stocky Galaxias uses restored habitat, but do not use a single non-detection to declare failure because the species is patchily distributed and may occupy short stream sections.
  • Continue monitoring for the period required by the approval and extend it after fire, drought, flood, major maintenance or detection of an invasive fish.

Sources