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White-winged Triller (Lalage tricolor)

The White-winged Triller is a small insect-eating passerine of open woodland, grassy woodland, scrub and tree-lined waterways across mainland Australia. It is an uncommon breeding summer migrant in the ACT and is listed as Vulnerable there, so clearing can remove nesting trees, fallen timber and insect-rich ground habitat.

Conservation status

Australian Capital Territory, Nature Conservation Act 2014: Vulnerable.

Breeding season

Timing varies across Australia. The table reflects the best documented pattern for southern Australia and the ACT, where the species is a summer breeding migrant. It is present in northern Australia throughout the year.

Month values are January to December: 0 means not typical, 1 means occurs, and 2 means peak or highest likelihood.

  • Movement and arrival in southern Australia: Southern birds return from the north from August, with most ACT birds arriving in October. The species is a breeding migrant to southern Australia from August to March.
  • Breeding: The general breeding season is September to December. ACT breeding records extended from November to February.
  • Young in nest or dependent: Nestlings remain in the nest for approximately 12 days. Dependent young may be present during and after the documented laying period, especially from October to February.
  • Departure from southern Australia: The species is among the first summer migrants to leave the ACT, departing from mid-summer through to late autumn. It may remain in northern Australia, where it is seen throughout the year.
  • Highest clearing risk: Risk is highest when birds are present in southern Australia and breeding or caring for young, particularly September to February. In northern Australia, birds may be present year round, so local habitat and breeding observations should guide timing.

Identification

The White-winged Triller is a compact bird with long wings, a relatively long rounded tail and a short, slender bill. It has an undulating flight and often shuffles or refolds its wings after landing.

Adults are 16 to 19 cm long. Breeding males are glossy black on the head, back, shoulders and wing coverts, with white underparts and a broad white shoulder bar. The wings show a distinctive black and white netted pattern.

Females are mainly pale brown above, with a dark line through the eye, a faint pale eyebrow and buff-washed underparts. Non-breeding males resemble females but retain black flight feathers and tail, and usually have a greyer rump. Immatures are similar to females.

Length: 16 to 18.5 cm in the ACT conservation advice; 17 to 19 cm in the Australian Museum account.

Weight: 25 to 25.4 g.

Identification: Similar species

Check the sex and plumage stage before identifying the bird. Breeding males are the easiest to recognise because of the black and white pattern and broad white shoulder bar, while females and non-breeding males are more easily confused with other brown trillers.

The supplied references identify Varied Triller, White-shouldered Triller, Pied Honeyeater, Long-tailed Triller, Biak Triller, Rufous-bellied Triller and Pied Triller as possible comparison species. The former name Lalage sueurii is no longer the accepted name for this species in the ACT advice and is now associated with White-shouldered Triller.

  • Use the broad white shoulder bar, black and white wing pattern and glossy black breeding plumage to separate a breeding male from brown trillers.
  • Treat a brown bird as potentially female, immature or non-breeding male until the tail, wing pattern and eye stripe have been checked.

Identification: Field signs

The call is a descending series described as ‘chiff-chiff-joey-joey-joey’. Males are particularly noisy during breeding and may sing while flying slowly over the territory with wings and tail spread.

The nest is a small, shallow, well-camouflaged cup made from bark, grass, rootlets, fine material and spider web. It is placed on a horizontal branch or in a fork, and the species sometimes uses an empty mud nest of a Magpie-lark. Several pairs may nest in one tree.

  • Listen for a loud, repeated trill or descending ‘chiff-chiff-joey-joey-joey’ sequence during the breeding period.
  • Inspect horizontal branches and forks in trees for small, frail or well-camouflaged cup nests.
  • Record repeated use of one tree by several pairs as potential semi-colonial breeding activity.

Distribution: Australian range

The White-winged Triller occurs across mainland Australia, with additional records from Indonesia and New Guinea. It is resident near water in northern Australia, seasonally migratory or nomadic through central and southern Australia, and a vagrant in northern Tasmania.

The species is found across the Australian mainland. It is more common in south-eastern Australia, the far north of the Northern Territory, the Kimberleys and western Western Australia. The supplied sources do not provide a finer state by state or named bioregion range.

In the ACT it is an uncommon breeding summer migrant. Birds generally begin returning from the north in August, with most arriving in October, and leave from mid-summer through to late autumn.

  • Expect year-round presence in northern Australia, particularly near water.
  • Expect seasonal presence in central and southern Australia, including the ACT.
  • Treat northern Tasmania records as casual or vagrant occurrences rather than a regular breeding range.

Distribution: Strongholds and trend

In the ACT region, historical records were widespread and included Hall, Mulligans Flat, Gooroo, the Pinnacle, Campbell Park and the Gigerline to Tharwa area. ACT records vary substantially between years.

The ACT conservation advice reports a 54 percent decline in reporting rate over the 20 years between two national atlases, compared with a 16 percent national decline. These figures are reporting rates rather than direct population estimates.

ACT reporting rate change: Declined by 54 percent over 20 years between atlases.

National reporting rate change: Declined by 16 percent over the same comparison.

ACT 2016 to 2017 records: 376 birds recorded, compared with 731 in 2015 to 2016.

ACT 2016 to 2017 reporting rate: 1.2 percent, compared with a 10 year and 30 year average of 3.5 percent.

ACT 2016 to 2017 breeding records: 14 records, compared with 25 in 2015 to 2016.

Habitat: Vegetation communities

White-winged Trillers use open, lightly timbered habitats with an open shrub layer and grassy ground cover. Habitat use spans wetter northern and drier southern parts of Australia.

Recorded habitats include open woodland and forest, eucalypt woodland, mallee, Acacia scrub, spinifex and tree-lined waterways in semi-arid regions. In the ACT, the species is mainly associated with grassy woodland, including Yellow Box to Red Gum, Apple Box, Candlebark and, less commonly, Snowgum woodland.

The species may also occur in nearby scrub where woodland and open ground are connected.

Habitat: Structure to retain

Important habitat features include large living and dead trees for perching, roosting, foraging and nesting, together with grass and fallen timber that support insects and other invertebrates.

An open shrub layer and grassy ground cover are consistent features of the described habitat. Avoid assessing a woodland only by canopy cover, because fallen timber and ground-layer condition also affect the species' feeding habitat.

  • Retain large mature living trees and dead standing trees.
  • Retain fallen timber, grassy ground cover and an open shrub layer.
  • Protect tree-lined waterways and adjacent open woodland where they occur together.

Habitat: Climate and elevation

The sources describe the species by climate and habitat region rather than by elevation. It occurs in wetter northern and drier southern regions, is resident near water in the north, and moves seasonally through central and southern Australia.

Foraging habitat: Diet

The White-winged Triller is primarily an insectivore that feeds across foliage, in the air and on or near the ground. Foraging habitat is closely linked to grassy ground cover, shrubs, fallen timber and flowering trees.

Food includes insects such as winged termites, ants, grasshoppers and caterpillars. The species also takes other invertebrates, fruit, seeds and occasional nectar.

  • Retain insect-producing grass cover and fallen timber.
  • Retain shrubs and flowering vegetation that provide insect prey and occasional nectar.

Foraging habitat: Foraging behaviour

The species forages busily on foliage in high trees and may hawk flying insects from a high perch. It also takes food on the ground, in shrubs and among fallen timber.

A feeding area may lie within the breeding territory or up to 1 km away. A nest tree therefore does not necessarily contain all habitat used by the breeding pair.

Reported feeding distance: Foraging may occur within the breeding territory or up to 1 km away.

  • Survey high foliage, elevated perches, shrubs, grassy ground and fallen timber.
  • Consider suitable foraging habitat up to 1 km from a nest or suspected breeding territory when assessing construction impacts.

Breeding habitat: Breeding biology

Breeding occurs in trees within open woodland and grassy woodland, usually where suitable branches, insect-rich ground habitat and nearby cover are available. Both parents incubate and brood the nestlings.

Pairs build small, shallow cup nests from bark, grass, rootlets, fine material and spider web. Nests are placed on horizontal branches or in forks. Breeding may be semi-colonial, with several pairs nesting in one tree while each pair retains its own foraging territory.

Breeding season: Generally September to December; ACT breeding records occurred from November to February.

Clutch size: Two to three eggs.

Incubation: Approximately 14 days.

Time in nest: Approximately 12 days.

Age at maturity: Approximately 1.3 years.

Lifespan: Average 2.6 years and maximum 5.139 years in the supplied reference.

Parental care: Both parents incubate and brood nestlings.

Breeding habitat: Breeding habitat features

Breeding habitat includes large living trees and dead standing trees with suitable horizontal branches or forks. Nearby grass, shrubs and fallen timber support the invertebrates needed by adults feeding themselves and their young.

  • Inspect all mature and dead trees in or near open woodland before clearing.
  • Retain trees containing active nests and avoid disturbing nest trees during the breeding period.
  • Maintain nearby grassy ground cover and fallen timber rather than isolating retained nest trees within cleared areas.

Sheltering habitat: Roosting and resting sites

The supplied sources do not describe specialised refuges such as dens, burrows or hollows. Shelter and resting opportunities are provided mainly by trees, branches, woodland cover and ground-layer structure.

Large living and dead trees are identified as important for perching and roosting. The species also uses high perches when hunting flying insects and occurs in open woodland, scrub and tree-lined waterways.

  • Retain large live trees, dead standing trees and connected woodland cover.
  • Include high branches and prominent perches in habitat retention and pre-clearing inspections.

Sheltering habitat: Ground cover and nest shelter

Grass, shrubs and fallen timber provide cover and support prey on or near the ground. Nests are small and well camouflaged, so they may be missed during rapid inspections.

  • Inspect horizontal branches and forks in trees for small cup nests before clearing or pruning.
  • Retain fallen timber, shrubs and grassy ground cover where practicable.
  • Do not assume that a cleared area is unused because no nest is visible; birds may forage up to 1 km from the breeding territory.

Threats: Clearing and fragmentation

The main documented threat is loss and degradation of woodland habitat. Project impacts can remove nest trees, foraging trees, fallen timber and the grassy ground layer used to support insect prey.

Clearing and degradation reduce the amount and quality of woodland habitat. Removal of live and dead timber reduces nesting, perching, roosting and foraging opportunities, while loss of grass and fallen timber reduces insect availability.

Fragmenting woodland can separate nest trees from foraging areas. This matters because feeding areas may extend up to 1 km from the breeding territory.

  • Avoid clearing suitable woodland, especially patches with mature trees, dead timber, grass and complex ground structure.
  • Map nest trees, mature trees, dead standing timber, fallen timber and nearby foraging habitat before works.
  • Retain habitat around nest trees rather than leaving isolated trees in a cleared work area.

Threats: Grazing, fire and timber removal

Overgrazing reduces ground-layer complexity and can lower the availability and quality of foraging habitat. Removal of fallen timber for firewood has the same documented effect.

The ACT conservation advice identifies adverse fire effects as a management issue and recommends minimising impacts of fire on woodland areas.

  • Control intensive grazing in retained habitat.
  • Do not remove fallen timber or dead standing trees unless required for an immediate safety reason and authorised by the relevant approval.
  • Plan fire management to retain woodland structure, grass cover and fallen timber.

Threats: Construction disturbance and seasonal risk

Construction, vegetation removal and pruning can disturb territorial males, active nests and dependent nestlings during the breeding season. The species is present in southern Australia during the warmer months, when breeding activity is most likely.

The supplied sources do not identify species-specific evidence for road mortality, introduced predators, disease or hydrology change. These issues should still be considered where a project removes woodland, alters waterways or increases access to habitat, but they are not documented as primary threats in the supplied material.

  • Complete targeted pre-clearing checks for adults, calls and small cup nests before works.
  • Avoid clearing or noisy works around active nests during the local breeding period where practicable.
  • Retain tree-lined waterways and adjacent woodland where works occur near water.

Survey methodology: 1. Habitat assessment and transects

Survey this diurnal bird in open woodland, grassy woodland, mallee, Acacia scrub, spinifex and tree-lined waterways. Give priority to areas with mature living and dead trees, grassy ground cover and fallen timber, because these features provide perches, nest sites and insect-rich feeding habitat.

Map all suitable habitat within and near the disturbance area before field surveys begin.

Use systematic daytime walking transects through eucalypt woodland, grassy woodland, mallee, Acacia scrub, spinifex and tree-lined waterways.

Record birds seen or heard, the number of birds, sex or plumage where identifiable, behaviour, GPS location, habitat type and distance from the proposed works.

Include areas with large living trees, dead standing trees, fallen timber, grassy ground cover and an open shrub layer.

Body length: Approximately 16 to 19 cm.

Typical social unit: Usually seen in pairs; breeding can be semi-colonial.

Potential feeding distance: Feeding areas may be within the breeding territory or up to 1 km away.

  • Survey during daylight because the species is diurnal and forages in tree foliage, shrubs, on the ground and in the air.
  • Search high tree perches, foliage, woodland edges, grassy areas and fallen timber.
  • Record flying birds separately from birds using the site for feeding, nesting or territorial behaviour.
  • Do not treat the absence of birds during one visit as evidence that suitable habitat is unused.

Survey methodology: 2. Breeding-season checks

In southern Australia and the ACT, schedule repeat daytime checks during the breeding and summer-migrant period.

Look for males singing in flight, males defending nesting areas, pairs, adults carrying nesting material and repeated visits to a tree or branch.

Inspect suitable horizontal branches and forks from the ground where this can be done safely and without disturbing birds.

Nest placement: Small shallow cups occur on horizontal branches or forks.

Nest materials: Grass, bark, rootlets, fine material and spider web.

Clutch size: Two to three eggs according to the Australian Museum source; two eggs in the additional breeding dataset.

Incubation and nest period: About 14 days of incubation and 12 days in the nest.

  • Prioritise surveys from August to March in southern Australia, with particular attention to September to December when breeding is reported.
  • In the ACT, check sites from August to February, noting that most birds arrive in October and may leave from mid-summer to late autumn.
  • Record nests, territorial behaviour and the number of birds using each habitat patch.
  • Do not approach or handle an active nest unless authorised under the applicable wildlife legislation and project approval.

Survey methodology: 3. Call and behaviour searches

Use quiet listening periods during daytime transects because males are conspicuous when singing and calling during the breeding period.

Record the direction and approximate location of calls, then check nearby trees, woodland edges and grassy feeding areas for birds.

Use calls and flight behaviour as supporting evidence, not as a substitute for visual confirmation where the project decision depends on species identification.

Male breeding plumage: Glossy or deep black above with white underparts and a broad white shoulder bar.

Female and non-breeding plumage: Predominantly brownish, with a pale brow and a dark line through the eye.

Flight: Undulating flight, with wing shuffling or refolding after landing.

  • Listen for the descending call described as a repeated fast-note or canary-like trill.
  • Record males singing in flight, birds chasing other males and birds using high perches.
  • Compare plumage with similar trillers where identification is uncertain, especially in non-breeding plumage.
  • Do not use nocturnal spotlighting as a primary method for this species because the available sources describe it as a daytime bird.

Survey methodology: Minimum effort and reporting

The supplied documents do not specify a standard number of transects, survey hours, nights or trap nights for White-winged Triller detection.

Set the survey area, number of visits and timing through the relevant state survey guidance, project risk assessment and approval conditions.

  • Survey all suitable habitat within the impact area and any retained habitat that may receive relocated fauna.
  • Repeat surveys when the first visit occurs outside the local breeding or movement period, when weather reduces detectability, or when habitat is difficult to inspect.
  • Record date, start and finish time, weather, observers, method, survey area, effort, detection conditions and all negative results.
  • Submit confirmed records and significant breeding observations to the relevant state wildlife database and the Atlas of Living Australia where appropriate.
  • Report the ACT status separately from national status because the species is listed as Vulnerable in the ACT but is not listed under the EPBC Act in the supplied project information.

Before habitat disturbance: Avoid and minimise habitat loss

Avoid clearing White-winged Triller habitat wherever practicable. Design the work area around the woodland structure and ground layer that support nesting, perching and insect foraging.

Retain large living trees, dead standing trees, fallen timber, grassy ground cover and an open shrub layer.

Retain woodland patches with complex habitat structure, especially where birds, nests or repeated feeding activity have been recorded.

Keep connected areas of woodland and avoid creating isolated remnants where the design allows.

Key habitat features: Large living and dead trees, grassy feeding areas and fallen timber.

Known ACT habitat: Grassy Yellow Box, Red Gum, Apple Box, Candlebark and, less commonly, Snowgum woodland.

  • Avoid removing live or dead timber for access, firewood, temporary works or site tidiness.
  • Avoid intensive grazing and other activities that reduce grass cover or remove fallen timber.
  • Keep construction plant, stockpiles, access tracks and laydown areas out of retained woodland and known feeding areas.
  • Use an ecologist to set site-specific no-go areas around nests, retained trees and other occupied habitat features.

Before habitat disturbance: Approvals and work planning

Confirm the species status and approval pathway for the project location before clearing or construction starts.

The supplied information identifies the White-winged Triller as Vulnerable in the ACT and not listed under the EPBC Act.

  • Check whether the action requires an EPBC Act referral for other listed matters or because the project information has changed.
  • Obtain any required state or territory wildlife permits, threatened species approvals and animal handling authorisations.
  • Prepare a fauna management plan that identifies survey results, exclusion areas, clearance sequencing, stop-work triggers, handling responsibilities and reporting requirements.
  • Schedule avoidable clearing outside the local breeding period where practicable, particularly September to December in southern Australia and the ACT.
  • Stage clearing so retained woodland remains available while adjacent works proceed.

Before habitat disturbance: Pre-clearance preparation

Complete a pre-clearance inspection immediately before works, with timing set by the fauna management plan and approval conditions.

Mark retained trees, dead timber, fallen logs, nests, feeding areas and no-go zones before machinery arrives.

Check both the proposed clearing footprint and nearby retained habitat for birds and active nests.

  • Use exclusion fencing, bunting or other visible barriers where these controls will protect retained habitat from machinery and vehicle entry.
  • Brief all workers on the species appearance, call, habitat features, stop-work triggers and reporting chain.
  • Confirm that a suitably authorised fauna spotter catcher is available for each clearing shift.
  • Plan a safe method for lowering or relocating any dead timber or other habitat feature that must be moved.

During habitat disturbance: Daily controls and spotter catcher duties

Use active supervision during clearing and construction. The fauna spotter catcher must have authority to pause work when a bird, nest or habitat feature could be affected.

Inspect the work area each day before machinery starts and after breaks or changes in the work front.

Keep the fauna spotter catcher in direct communication with the machine operator and supervisor.

Clear in stages from the edge of the approved footprint towards retained habitat so birds can move away from active machinery.

  • Maintain all marked exclusion zones and prevent plant, vehicles, spoil and materials from entering them.
  • Use the lowest disturbance method that achieves the approved work, particularly near retained trees, nests and fallen timber.
  • Stop the relevant activity when the spotter catcher cannot maintain a clear view of the clearing front.
  • Record daily inspections, weather, personnel, machinery, cleared area, fauna observations, incidents and corrective actions.

During habitat disturbance: Habitat feature handling

Treat large living trees, dead standing trees and fallen timber as habitat features even when no bird is visible.

The supplied sources do not identify White-winged Triller as a hollow-dependent species, but mature and dead trees can provide perches, roosts, nest sites and foraging structure.

  • Do not fell or remove habitat trees, dead timber or logs unless the feature is within the approved footprint and the management plan allows it.
  • Check branches, forks and horizontal limbs for the species' small shallow nests before tree or branch removal.
  • Retain or place suitable fallen timber in nearby retained woodland when approved removal is unavoidable.
  • Do not disturb wetlands, drainage lines or tree-lined waterways without checking for birds using adjacent woodland and ground-foraging areas.
  • Do not use nest boxes as a substitute for retaining suitable trees unless an ecologist and the approval authority identify them as appropriate.

During habitat disturbance: If a bird is found

Pause work that could affect the bird and allow the fauna spotter catcher to assess its location, condition and behaviour.

Do not chase, catch or relocate a healthy flying bird unless this is authorised and the authorised handler considers it necessary.

Use nearby retained woodland with suitable trees, grassy ground cover and fallen timber as the first relocation option when relocation is approved.

  • Only an appropriately authorised person may handle the bird or remove it from danger.
  • Keep handling time, noise and physical restraint to the minimum needed for safety and compliance.
  • Place an injured bird in a secure, quiet, appropriately ventilated container and arrange prompt assessment by a veterinarian or authorised wildlife carer.
  • Stop work and establish an exclusion zone if a nest, dependent young, injured bird or repeated territorial activity is found in the impact area.
  • Resume work only after the fauna spotter catcher, ecologist and site supervisor have agreed on controls and recorded the decision.

After habitat disturbance: Post-clearance checks

Keep fauna controls in place until the site is stable and the project team has confirmed that no further birds, nests or habitat features are at risk.

Inspect the cleared area and adjoining retained woodland after each clearing stage.

Check for injured or trapped birds, damaged nests, isolated habitat features and unauthorised encroachment into retained woodland.

Repeat checks during the local breeding period where clearing has occurred near suitable nesting trees.

  • Remove temporary fencing only when machinery and construction risks have passed and the management plan allows it.
  • Repair damaged exclusion fencing and reinstate any displaced habitat markers.
  • Confirm that retained trees, dead timber, logs and grassy feeding areas remain available and undamaged.
  • Document all post-clearance inspections, findings, incidents and unresolved risks.

After habitat disturbance: Monitoring and reporting

Monitor retained and rehabilitated woodland for White-winged Trillers during the seasons specified in the fauna management plan.

Compare records of presence, pairs, breeding activity and habitat condition with the pre-disturbance survey.

  • Use the same observation locations and recording fields where possible so results can be compared over time.
  • Report new sightings, nests, injuries, deaths, relocations, breaches and corrective actions to the project environmental officer.
  • Submit required records to the relevant state wildlife database and meet all approval reporting conditions.
  • Escalate declining use of retained habitat, repeated injury or failure of rehabilitation to the project ecologist and approval authority.

After habitat disturbance: Offsets and residual impacts

Assess offsets only after avoidance, minimisation and rehabilitation measures have been applied.

Any offset or compensatory measure must address the woodland habitat features and threatening processes identified for the project and the relevant jurisdiction.

  • Document the area and condition of habitat removed, retained, restored and protected.
  • Include the loss or retention of mature trees, dead timber, grassy ground cover and connected woodland in the residual-impact assessment.
  • Do not describe an offset as replacing an occupied nest or established woodland habitat unless the relevant approval framework accepts that conclusion.

Rehabilitation actions: Restore woodland structure

Rehabilitation should rebuild open woodland structure and the ground layer used by White-winged Trillers for nesting, perching and insect feeding. Protect restored areas from the same clearing, timber removal, grazing and fire pressures that caused the impact.

Re-establish locally appropriate eucalypt woodland or other native woodland communities identified in the project ecological assessment.

Use local provenance species where required by the approval or restoration plan, with plant selection matched to the pre-disturbance community.

Restore an open shrub layer with grassy ground cover rather than creating dense understorey that removes the species' open foraging conditions.

Habitat structure to restore: Open woodland, grassy ground cover, an open shrub layer, mature trees and fallen timber.

  • Retain and protect surviving mature trees and dead standing trees during rehabilitation.
  • Plant or regenerate trees that can provide future perches, nest branches and foliage for insect foraging.
  • Reinstate fallen timber in stable locations where it will not create a fire, erosion or access hazard.
  • Do not remove dead timber solely to make the rehabilitated site look tidy.

Rehabilitation actions: Manage threats and site condition

Manage grazing, weeds and fire so the ground layer continues to support insects and other invertebrates.

Apply fire planning that minimises adverse effects on woodland structure and retains mature and dead timber where safe.

  • Control weeds that displace native grasses, shrubs or regenerating trees.
  • Prevent intensive grazing in rehabilitation areas while plants establish and maintain sufficient ground cover.
  • Avoid broad removal of fallen timber during fire protection or maintenance works.
  • Use predator control only where it is required by the approved management plan and can be implemented lawfully and humanely.
  • Design drainage and wetland works so tree-lined waterways and adjacent woodland remain available for foraging.

Rehabilitation actions: Nest features and monitoring

Retain natural nest branches and forks as the preferred measure because the species builds small cups on horizontal branches or forks.

Use nest boxes only where an ecologist confirms that they are suitable for the local project and where natural nesting structure cannot be retained.

Breeding period for monitoring: September to December is the reported breeding season; the species occurs in southern Australia mainly from August to March.

Nest materials: Grass, bark, rootlets, fine material and spider web.

  • Monitor plant survival, tree regeneration, grass cover, weed cover, fallen timber retention and fire or grazing impacts.
  • Survey rehabilitated areas during the local August to March movement and breeding period in southern Australia, with particular attention to September to December.
  • Record White-winged Triller presence, pairs, territorial behaviour, feeding activity and breeding records.
  • Set success measures in the rehabilitation plan for habitat structure and species use, and apply corrective actions when those measures are not met.
  • Continue monitoring for the period required by the approval, offset agreement or rehabilitation plan.

Sources