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Green Rosella (Platycercus caledonicus)

The green rosella is a large Tasmanian parrot found in Tasmania and Bass Strait islands. The King Island subspecies is listed as Vulnerable nationally and in Tasmania, with fewer than 500 mature individuals estimated and breeding habitat concentrated in eucalypt forest around Pegarah State Forest, so clearing of mature hollow-bearing trees requires particular care on King Island.

Conservation status

Commonwealth, EPBC Act 1999: Vulnerable.

Tasmania, Threatened Species Protection Act 1995: Vulnerable.

Breeding season

The pattern below applies chiefly to the King Island subspecies. Birds are generally resident during the breeding season, with local movements and wider island use outside that period.

Green rosellas may be detected at any time of year. Outside the breeding season, survey coverage should include forest remnants, scrub, shelterbelts and homestead gardens across King Island.

  • Breeding and laying: Pairs nest annually from September to February, usually in tree hollows or broken limbs.
  • Incubation and young in nest: Incubation lasts 19 to 23 days. Fledglings leave at about five weeks after hatching.
  • Dependent young: Young remain dependent on their parents for about two weeks after fledging, so dependence may extend into March for late-season nests.
  • Local movement and flocking: The subspecies is generally sedentary or resident during breeding but may be locally nomadic outside the breeding season. Flocks are more typical in autumn and winter, and birds may occur across King Island.
  • Highest clearing risk: September to February is the highest risk period because adults may be incubating, feeding nestlings or caring for dependent fledglings. Clearing at any time can remove nest trees, food resources or communal roosts.

Identification

The green rosella is a large, broad-tailed parrot. On King Island, the listed subspecies cannot be reliably separated by appearance from the other green rosella subspecies, so location and habitat are important when assigning conservation significance.

Adults have dark green upperparts with black mottling, a rich yellow head, neck and underparts, a red forehead and blue cheek patches. The rump is olive-green, and the wings and tail have blue or violet-blue edging. The tail is long and broad.

Juveniles have a dull yellow-green head and underparts, a dull green body and an under-wing stripe that is absent in adults.

Length: About 37 cm.

Weight: 100 to 150 g.

Identification: Sex and age differences

Males and females are similar, but females are generally greener and duller and have a smaller bill. Adult plumage is brighter yellow than juvenile plumage.

The two recognised subspecies are not readily distinguished morphologically. A green rosella recorded on King Island should therefore be treated as the listed King Island subspecies for field planning and assessment purposes.

Identification: Field signs and similar species

The species is usually observed singly, in pairs or in small flocks, generally with fewer than 20 birds. Flocks are more typical in autumn and winter, and birds may roost communally.

The most useful breeding sign is a large tree hollow, broken branch or other cavity being used by a pair. Wall cavities and shingle roofs have also been documented as nest sites. There are no confusing species reported on King Island, but plumage alone should not be used to separate the King Island subspecies from the mainland Tasmanian subspecies.

  • Check mature and partially dead eucalypts, broken limbs, trunk cavities, wall cavities and concealed roof spaces where rosellas are seen repeatedly.
  • Record repeated pair activity, birds carrying food, adults entering or leaving cavities, begging young and communal roosting sites.
  • Treat a green rosella using forest, shelterbelts or homestead gardens on King Island as potentially relevant to the listed subspecies, including outside the breeding season.

Distribution: Range and stronghold

The species is endemic to Tasmania and Bass Strait islands. The nationally and Tasmanian listed King Island subspecies is endemic to King Island, while the other subspecies occurs across Tasmania and nearby Bass Strait islands.

Platycercus caledonicus occurs in Tasmania and Bass Strait islands. Platycercus caledonicus brownii occurs only on King Island, northwest of Tasmania.

The King Island subspecies is largely confined to eucalypt forest around Pegarah State Forest during the breeding season. Outside the breeding season it may occur elsewhere across King Island, including other forest remnants, scrub, shelterbelts and homestead gardens.

  • King Island is the relevant state and bioregional range for the listed subspecies.
  • Known habitat areas include Pegarah State Forest, larger forest remnants, Lavinia State Reserve, Seal Rocks State Reserve, Kentford Forest Nature Reserve and Kentford Forest Conservation Area.
  • The King Island subspecies may use the wider island outside the breeding season, so surveys should not be restricted to the breeding stronghold.

Distribution: Population and trend

The King Island population is small. Earlier estimates placed the total population between 250 and 1,000 mature individuals, while the Tasmanian listing statement gives an estimate of fewer than 500 mature individuals.

A 2015 survey involved 114 people, 401 survey hours and 82 sites, where 78 green rosellas were counted. The survey concluded that it was extremely unlikely that the island population exceeded 1,000 birds. Reliable recent population trend data are not available.

King Island area of occupancy: About 50 km2 during the breeding season.

King Island extent used outside breeding season: Approximately 800 km2, representing the island-wide range described in the listing statement.

Estimated mature population: Fewer than 500 mature individuals in the Tasmanian listing statement; earlier estimates were 250 to 1,000 mature individuals.

Known population trend: No reliable recent trend has been established.

Habitat: Vegetation and structure

Green rosellas use habitats with tree cover, but the King Island subspecies depends most strongly on dry and wet eucalypt forest for breeding. Remaining habitat is fragmented after extensive vegetation clearing.

The King Island subspecies mainly inhabits dry and wet eucalypt forests. It also uses scrub, shelterbelts and homestead gardens, particularly outside the breeding season.

Important structural features include mature eucalypts, hollow-bearing trees, broken limbs, a connected or nearby canopy, and vegetation that supplies seeds, fruit, flowers and insects. Breeding habitat is concentrated in forest, while foraging may occur across a wider range of tree-covered and semi-open habitats.

  • Retain mature and hollow-bearing eucalypts, including trees with broken branches and partially dead limbs.
  • Retain linked forest patches, shelterbelts and native vegetation around retained trees.
  • Map trees with hollows and repeated rosella activity before clearing, pruning, road widening or infrastructure placement.

Habitat: Habitat availability

Approximately 70 percent of King Island's native vegetation has been cleared, mainly for agriculture. The remaining suitable habitat occurs in a highly fragmented and developed setting.

No specific elevation limit is provided. The species is described from lowland dry and wet eucalypt forest and other tree-covered habitats on King Island.

Foraging habitat: Food

Green rosellas forage from the ground to the canopy. They are mainly herbivorous but also take insects and larvae, and may travel between forest, scrub, shelterbelts and gardens to feed.

The diet includes seeds of grasses, shrubs, eucalypts and other trees, as well as berries, nuts, fruit, flowers, buds, nectar, insects and insect larvae. Psyllids and other insects may be taken.

On King Island, fruit from weeds such as hawthorn and large-leaf cotoneaster is also consumed.

  • Retain seed-producing grasses, shrubs and eucalypts, flowering trees, fruiting plants and native understorey around forest remnants.
  • Avoid removing food trees and flowering or fruiting shrubs during works where rosellas are regularly feeding.
  • Inspect ground, shrub and canopy layers because the species can forage at all levels.

Foraging habitat: Foraging behaviour

Birds forage singly, in pairs or in small flocks, usually with fewer than 20 birds. In closed forest they mainly forage in the mid to upper canopy, but they also feed on the ground and in lower vegetation.

No species-specific foraging distance or home-range size is provided. During the non-breeding season, birds may occur across King Island rather than remaining near the Pegarah breeding area.

Breeding habitat: Breeding biology

Breeding is associated mainly with dry and wet eucalypt forest containing suitable cavities. Pairs may use natural hollows, broken limbs and, where natural cavities are unavailable, buildings or other artificial structures.

Breeding season: September to February.

Pairing: Adults form monogamous pairs.

Age at first breeding: The listing statement reports nesting annually from about three years of age.

Clutch size: Usually 4 to 5 eggs.

Incubation: The female incubates the eggs for 19 to 23 days.

Nestling and fledging: Fledglings leave the nest at about five weeks after hatching and remain dependent on their parents for about two weeks after fledging.

Broods: One clutch is normally laid each year; repeat clutches are usually laid in the same hollow.

Lifespan: Maximum longevity in the wild is estimated at 10.2 years.

Breeding habitat: Breeding site requirements

Natural nests are in hollows or broken branches of tall trees, usually in dry or wet eucalypt forest. Disused buildings, wall cavities, concealed trunk forks and shingle roofs have also been used.

Both adults care for the young. Breeding sites may be reused, and scarcity of suitable hollows can limit breeding capacity.

  • Before clearing or pruning, inspect mature eucalypts and broken limbs for cavities, entry activity, adults carrying food and begging young.
  • Retain hollow-bearing trees and nearby canopy wherever practicable.
  • Do not assume that an unoccupied-looking hollow is unused, because repeat clutches may be laid in the same hollow and occupation may be seasonal.
  • Assess nest boxes carefully because competition from starlings has limited the success of previous trials.

Sheltering habitat: Hollows and cavities

The main shelter and breeding structures are tree hollows and broken limbs in eucalypt forest. Green rosellas also roost communally and may use buildings or other concealed cavities.

Suitable nest sites include hollows in trunks or limbs, broken branches, concealed forks of tree trunks, wall cavities and shingle roofs. The documents do not provide entrance dimensions, hollow depth or tree diameter thresholds.

Hollow availability is a limiting factor on King Island. Brush-tailed possums, exotic birds and European honeybees may compete for available hollows.

  • Retain living and standing dead trees with hollows, broken limbs and other cavities.
  • Inspect buildings, wall cavities and roof structures where rosellas are seen entering or leaving.
  • Record the location, tree condition, cavity height and observed use of every potential nest tree before works.

Sheltering habitat: Roosting

Roosting is communal, at least during winter. Birds return to the same roost each evening and leave shortly after daybreak throughout the year.

Specific roost tree species, roost dimensions and roost locations are not provided. Repeated evening arrivals and early morning departures are useful indicators of a roost site.

  • Schedule pre-clearing checks around likely roost vegetation near dusk and shortly after daybreak.
  • Avoid unnecessary disturbance of repeatedly used communal roosts, particularly during autumn and winter when flocks are more typical.

Threats: Clearing and fragmentation

The main risks to the King Island subspecies are loss of eucalypt habitat, loss of hollow-bearing trees, fire and competition for nesting cavities. Its small population and restricted island range increase the effect of localised clearing, severe fire, disease or other disturbance.

Historical clearing of native eucalypt forest is the primary cause of decline identified for the King Island subspecies. About 70 percent of the island's original native vegetation has been lost, and remaining forest occurs in fragmented patches.

Further clearing can remove feeding habitat, breeding trees, movement links and communal roosts. Removing mature hollow-bearing eucalypts is particularly damaging because replacement hollows take many years to form.

  • Avoid clearing dry and wet eucalypt forest, mature hollow-bearing trees, broken limbs and shelterbelts.
  • Treat isolated trees within cleared areas as potentially important because they may provide food, nest cavities or links between forest remnants.
  • Plan road, utility and construction footprints around retained hollow-bearing trees and their surrounding canopy where practicable.

Threats: Fire

Frequent fire can limit regeneration and reduce the future supply of hollow-bearing trees. Severe or uncontrolled wildfire can destroy large areas of foraging and breeding habitat.

A warmer climate may increase wildfire frequency and intensity. Fire planning should therefore consider both immediate habitat loss and the longer-term loss of mature trees and hollows.

  • Avoid unnecessary burning in remaining eucalypt habitat and retain mature trees after fire where safe.
  • Inspect recently burnt areas for surviving hollow-bearing trees and retained food resources before follow-up clearing.
  • Include hollow availability and habitat regeneration in fire management decisions.

Threats: Competition, predators and disease

Brush-tailed possums, starlings, other exotic birds and European honeybees may compete for nest hollows. Feral cats may threaten birds, eggs and chicks, and raptors can prey on adults.

Psittacine beak and feather disease occurs across Australia, including Tasmania. It can cause high mortality in nestlings, long-term immune suppression and feather or beak abnormalities. The virus spreads through crop feeding, excrement, feather and skin particles and can survive in nest hollows for years.

  • Do not move nest material, faeces, feathers, birds or nest-box equipment between sites without appropriate disease hygiene.
  • Use the Australian bird disease hygiene protocols when handling sick, injured or dead parrots and when inspecting nest boxes.
  • Report birds with severe feather or beak abnormalities through the relevant wildlife or biosecurity channels and minimise contact with other parrots.

Threats: Small population and disturbance

The King Island subspecies has fewer than 500 mature individuals in the Tasmanian listing estimate and occurs in a restricted island population. Stochastic events can therefore have a disproportionate effect.

No species-specific road mortality rate or hydrology threat is identified in the supplied documents. Project assessments should still check whether roads, drainage, altered water regimes or construction noise will remove forest, food plants, nest trees or roosts.

Survey methodology: 1. Diurnal searches and listening

Survey planning must account for the King Island green rosella, Platycercus caledonicus brownii, being a small, sedentary to locally nomadic parrot that nests in tree hollows. The documents do not provide a formal survey guideline, so methods should be designed by a suitably qualified ecologist around the species' habitat, breeding period and detectability.

Survey dry and wet eucalypt forest first, particularly areas with mature hollow-bearing trees. Also search scrub, shelterbelts and homestead gardens where these habitats occur near forest.

The species can be surveyed at any time of year. During the breeding season, from September to February, prioritise eucalypt forest. Outside the breeding season, search the wider island or project area because birds may occur in other habitats.

Record all visual and aural detections, including birds flying over the site, feeding birds, pairs, flocks, roosting birds and birds using hollows.

Breeding period: September to February

Typical social groups: Pairs or small flocks, usually fewer than 20 birds

Key breeding habitat: Dry and wet eucalypt forest with tree hollows

  • Use repeated visits and more than one observer where practical because the population is small and birds may occur in pairs or small flocks.
  • Search from early morning and during other periods of peak bird activity, avoiding periods of heavy rain, strong wind or poor visibility.
  • Map each detection and record the habitat, direction of flight, behaviour, flock size and whether the bird was inside or outside the proposed disturbance area.

Survey methodology: 2. Habitat and hollow assessment

Inspect the proposed disturbance area and adjacent retained habitat for mature eucalypts, hollow-bearing trees, broken branches, standing dead trees and other potential nest sites.

Record the location, tree species where identifiable, condition, hollow entrance characteristics and whether a hollow is occupied or shows signs of use. The species usually nests in a hollow or broken branch of a tall tree, but wall cavities and shingle roofs have also been documented.

Assess nearby retained forest, shelterbelts, scrub and gardens as potential feeding, roosting or movement habitat.

Estimated breeding area of occupancy: About 50 km2 in the Pegarah State Forest area

Estimated non-breeding extent of occurrence: About 800 km2 across King Island

Clutch size: Usually 4 to 5 eggs

  • Complete the habitat assessment before finalising the clearing footprint and machinery access routes.
  • Do not enter, block or modify a potential nest hollow during inspection unless this is authorised under the fauna management plan and carried out by a qualified person.
  • Treat an occupied hollow, repeated bird activity at a hollow or a dependent fledgling as a sensitive feature requiring project-specific controls.

Survey methodology: 3. Roost, feeding and movement observations

Search for communal roosts and repeated flight paths between forest remnants, feeding areas and nesting habitat. Birds return to the same roost each evening according to the Tasmanian listing statement.

Record feeding on grass, shrub and tree seeds, fruit, berries, nuts, flowers, nectar, insect larvae and insects. Weedy shrubs including hawthorn and largeleaf cotoneaster may also be used for food.

Use observation points that cover the proposed works, retained habitat and likely movement routes without disturbing roosting or nesting birds.

Activity pattern: Generally sedentary or resident during breeding, with local movements outside the breeding season

Foraging levels: Ground to canopy, mainly mid to upper canopy in closed forest

Roosting: Communal roosting has been recorded, including winter roosting

  • Repeat observations where a project could sever movement between forest remnants or remove mature hollow-bearing trees.
  • Record the time, location, number of birds, direction of movement, habitat used and any response to people, vehicles or machinery.
  • Do not rely on one negative visit to conclude that the species is absent.

Survey methodology: Minimum effort and reporting

  • Prepare a site-specific survey design that covers all proposed clearing, access routes, compound areas and adjacent habitat likely to be affected by noise, fire or altered access.
  • Use repeated systematic diurnal searches across the relevant breeding and non-breeding habitat, with effort and coverage stated clearly in the report; the supplied documents do not prescribe a fixed number of visits, hours, transect length or trap nights.
  • Do not use trapping, mist-netting or other capture methods unless they are necessary, approved and undertaken by appropriately authorised personnel; the species is a parrot that can be affected by disease transmission and handling stress.
  • Report survey dates, start and finish times, weather, observers, search area, method, effort, detection conditions, all records and the basis for concluding presence or likely absence.
  • Submit confirmed records and relevant negative survey information to the relevant Tasmanian wildlife database or other state biodiversity database, and provide records to the project approval authority where required.
  • If the project is outside King Island, confirm the taxon and listing before applying this profile because the supplied conservation documents concern the King Island subspecies, Platycercus caledonicus brownii.

Before habitat disturbance: Avoid and minimise

Plan the project around the species' dependence on eucalypt forest, mature hollow-bearing trees and a small, isolated population. On King Island, historical clearing has removed about 70 percent of native vegetation and breeding habitat is concentrated in the Pegarah forest area.

Principal habitat threat: Clearing and degradation of eucalypt forest

Hollow issue: Scarcity of nesting hollows may limit population size

  • Avoid clearing dry and wet eucalypt forest, mature hollow-bearing trees, broken branches and known nest or roost trees.
  • Retain connected forest remnants, shelterbelts and other tree cover between the work area and nearby breeding or feeding habitat.
  • Keep the disturbance footprint, access tracks, stockpiles, lighting and machinery areas outside retained habitat wherever practicable.
  • Treat occupied hollows, repeated use of a hollow, communal roosts and active feeding or fledgling areas as no-go features until a qualified ecologist confirms the controls.

Before habitat disturbance: Approvals and work planning

Tasmanian status: Vulnerable under the Threatened Species Protection Act 1995

Commonwealth status: Vulnerable under the EPBC Act

  • Check whether the action may significantly affect the EPBC Act listed vulnerable King Island green rosella and obtain project-specific environmental advice before work starts.
  • Obtain all required Tasmanian approvals and permits for clearing, taking, handling, possessing or relocating a listed animal.
  • Prepare a fauna management plan that identifies habitat to retain, survey results, exclusion zones, fauna handling authority, stop-work triggers, escalation contacts and reporting requirements.
  • Where practicable, stage clearing outside the September to February breeding period, while recognising that birds may use habitat outside the breeding season and that seasonal timing does not replace pre-clearance checks.
  • Stage works so that retained forest, nest trees, roosts and movement routes remain available before each clearing stage begins.

Before habitat disturbance: Site preparation

  • Complete a pre-clearance survey of the final disturbance footprint and adjacent retained habitat before machinery enters.
  • Mark approved clearing limits, retained trees, hollow-bearing trees, roosts, nest sites, movement corridors and exclusion zones on plans and on the ground.
  • Install exclusion fencing or other visible controls where they can protect retained habitat and prevent machinery from entering sensitive areas.
  • Brief all workers and plant operators on the species' appearance, nest-hollow dependence, reporting process and stop-work requirements.
  • Check for feral cats, exotic birds, honeybees and brush-tailed possums at or near nest hollows, and refer any proposed control action to the fauna management plan and relevant approvals.

During habitat disturbance: Daily controls and plant interface

The fauna spotter catcher should control the interface between machinery and retained habitat. Work must stop when an animal, occupied hollow or other unexpected habitat feature is found and the approved fauna management plan does not cover the situation.

  • Inspect exclusion fencing, tree markings and no-go areas at the start of each shift and after any movement of plant or materials.
  • Maintain a clear line of communication between the spotter catcher, machine operator, supervisor and environmental officer.
  • Direct machinery to work from the approved cleared side towards retained habitat only where the fauna management plan allows this sequence.
  • Use a spotter catcher with authority to stop plant immediately when a bird, fledgling, nest, hollow or other fauna is detected.
  • Keep noise, unnecessary vehicle movements, dust, lighting and worker access away from retained forest, nest trees and communal roosts.

During habitat disturbance: Hollows and habitat features

Tree hollows are a limiting resource for this subspecies, and the virus causing psittacine beak and feather disease can survive in nest hollows for years. Avoid disturbing hollows unless the action has been assessed and approved.

The supplied documents do not provide a species-specific protocol for relocating hollow-bearing trees, logs, rocks or other habitat features. Handle these features under the approved fauna management plan and relevant permit conditions.

  • Stop work before felling any hollow-bearing tree, tree with a broken nesting branch or tree suspected to contain a nest.
  • Have an authorised fauna spotter catcher inspect the feature and confirm the method before removal or modification.
  • Do not move a hollow, nest box or other nesting feature between sites without disease hygiene controls and approval from the responsible wildlife authority.
  • Do not use nest boxes as an automatic substitute for retaining mature hollow-bearing trees; nest-box trials on King Island had limited success because of competition from starlings.
  • Protect retained logs, dense vegetation and other cover where they form part of a connected forest or feeding area, unless the approved design requires their removal.

During habitat disturbance: Animal encounters and stop-work triggers

  • Stop work if a green rosella, fledgling, active nest, occupied hollow, injured bird or unexpected roost is found within the work area or its approved exclusion zone.
  • Do not chase, catch, handle, feed or house the bird unless the person is authorised and the action is permitted under the fauna management plan and applicable law.
  • If relocation is approved, move the bird only to nearby retained habitat identified in advance by the ecologist, and record the release location and condition of the bird.
  • Send an injured bird to an appropriately qualified wildlife carer or veterinarian through the approved project contact, rather than treating it on site.
  • Apply disease hygiene measures between birds, nest hollows, nest boxes, equipment and vehicles, because PBFD spreads through crop food sharing, excrement, feather and skin particles and contaminated hollows.
  • Resume work only after the fauna spotter catcher and environmental officer have documented the finding, applied the approved control and authorised restart.

During habitat disturbance: Records and escalation

  • Record every sighting, nest or hollow inspection, stop-work event, handling action, relocation, injury, mortality and restart decision on the day it occurs.
  • Include the date, time, location, habitat, bird number, behaviour, observer, machinery activity, photographs where permitted and action taken.
  • Escalate any mortality, nest damage, repeated disturbance, disease concern or breach of an exclusion zone to the project environmental officer and approval authority.
  • Update the site map after each encounter so that new roosts, flight paths, feeding areas and nest sites are included in subsequent work stages.

After habitat disturbance: Post-clearance checks

Post-clearance work should confirm that no birds, nests or dependent young remain in the affected area and that retained habitat controls are still working. Monitoring should be scaled to the level of habitat removed and the conditions of project approvals.

  • Inspect the cleared area, retained trees, access routes and exclusion zones after each clearing stage for injured birds, fledglings, damaged hollows and unexpected roosts.
  • Check retained hollow-bearing trees and nearby forest edges for stability, fire damage, weed spread and new access by machinery or stock.
  • Confirm that no debris, spoil, fencing, lighting or drainage changes have reduced access to retained feeding, nesting or roosting habitat.
  • Report any bird mortality, nest damage or habitat loss immediately through the project escalation process.

After habitat disturbance: Monitoring and reporting

Monitoring need identified in conservation advice: Regular and systematic surveys to determine population size and trend

Known competing hollow users: Brush-tailed possums, exotic birds, European honeybees and common starlings

  • Repeat diurnal searches in retained forest and around known breeding, roosting and feeding locations where the project removed or disturbed habitat.
  • Monitor the use and condition of any approved nest boxes or replacement hollows, including competition by starlings, brush-tailed possums, honeybees or other fauna.
  • Compare post-work records with pre-clearance records, including detections, flock size, roost use, hollow use and habitat condition.
  • Submit the final fauna report and verified records to the relevant Tasmanian wildlife database and approval authority where required.
  • Review monitoring results before releasing environmental bonds, removing exclusion fencing or starting the next project stage.

After habitat disturbance: Offsets and corrective action

  • Check whether the approval requires an offset, habitat security measure, restoration action or additional monitoring for unavoidable loss of habitat.
  • Prioritise protection and improvement of nearby eucalypt forest and hollow-bearing trees when selecting any approved conservation action.
  • Implement corrective action if monitoring shows loss of connectivity, repeated disturbance, failure of nest boxes, weed spread, increased fire risk or continued access by machinery or stock.

Rehabilitation actions: Restore habitat structure

Rehabilitation should restore connected eucalypt habitat and protect the nesting resources used by the King Island green rosella. The objective is to maintain and improve habitat within the species' range, not simply to replace the area cleared with young planting.

Habitat used: Dry and wet eucalypt forests, scrub, shelterbelts and homestead gardens

Foraging habitat: Ground, shrub and tree layers, including grass, eucalypt and other tree seeds, fruit, flowers and insects

  • Replant or encourage regeneration of locally appropriate dry and wet eucalypt forest species suited to the site and King Island provenance where relevant.
  • Retain existing mature trees and standing dead trees wherever safe, because replacement plantings will not provide large nesting hollows in the short term.
  • Restore connected tree cover between retained forest remnants, shelterbelts and feeding areas, with the layout agreed by the project ecologist.
  • Control weeds that reduce native forest regeneration, while recognising that the species may feed on fruit from some weedy shrubs and that removal should be planned rather than ad hoc.

Rehabilitation actions: Replace or protect nesting resources

Natural nest sites: Tree hollows or broken branches, usually in tall trees

Artificial nest-box history: Trials on King Island had limited success because of competition from starlings

  • Protect all retained hollow-bearing trees from fire, machinery impact, pruning and unnecessary removal.
  • Install nest boxes only where the fauna management plan and ecologist identify a demonstrated shortage of suitable hollows and a suitable location in retained habitat.
  • Design, install and inspect nest boxes under an approved species management protocol, including controls for starlings, brush-tailed possums, honeybees and other competitors.
  • Treat nest boxes as supplementary resources and continue to retain and recruit hollow-bearing trees through long-term forest management.
  • Record nest-box location, design, installation date, inspection results, occupants, breeding outcome and any disease or hygiene issue.

Rehabilitation actions: Fire, predators and disease

Fire risk: Frequent fire can limit habitat regeneration and affect hollow availability; severe wildfire can destroy foraging and breeding habitat

PBFD control: Prevention is the best control, and the virus can persist in nest hollows for years

  • Manage fire frequency and intensity so that frequent fire does not prevent habitat regeneration or reduce hollow availability.
  • Prepare a site-specific fire management approach for restored and retained forest, including protection of hollow-bearing trees and avoidance of severe uncontrolled fire.
  • Control feral cats where this is approved and feasible, and assess predation risk to adults, eggs and chicks as part of the rehabilitation plan.
  • Apply hygiene protocols to nest boxes, equipment and handling operations to reduce the risk of psittacine beak and feather disease, for which there is no effective treatment.

Rehabilitation actions: Success measures and follow-up

  • Monitor survival and regeneration of planted eucalypts and other native vegetation, retention and condition of hollow-bearing trees, weed cover, fire impacts and connectivity with retained forest.
  • Undertake regular systematic bird surveys using the same areas and methods used before disturbance, and report detections, flock size, roost use, feeding activity and breeding evidence.
  • Treat rehabilitation as successful only when habitat is protected, native forest is regenerating, key hollows or approved nest boxes remain available, and green rosellas continue to use the retained or restored area.
  • Continue monitoring for the period required by project approvals and adapt fire, weed, predator, disease and nest-box management when results show that the habitat objective is not being met.

Sources