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Ptunarra Brown Butterfly

SPECIES MANAGEMENT PROFILE

Oreixenica ptunarraPtunarra Brown Butterfly

Group:Arthropoda, Insecta (insects), Lepidoptera (butterflies, moths), Nymphalidae (Admirals)
Status:Threatened Species Protection Act 1995: endangered
Environment Protection and Biodiversity Conservation Act 1999: Endangered
Endemic
Status:
Found only in Tasmania
Click to enlarge
​​​​The Ptunarra Brown Butterfly (Oreixenica ptunarra) is a small brown and orange butterfly found only in Tasmania. The species occurs in Poa tussock grassland and grassy shrubland and woodland above 400 m in the north-west plains, Central Plateau, southern Midlands, the Steppes, and the eastern highlands. The female is similar in size to the male, but is a brighter orange. The caterpillars feed exclusively on the leaves of Poa grass. The adult flying season lasts only a few weeks in early autumn, during which time the butterflies mate and lay eggs on the tussocks. Large areas of this species’ habitat have been lost through conversion to pasture or plantation.  Over-grazing, over-burning and predation by the introduced European wasp can also lead to loss of this species from a site.

Key Points

  • Important: Is this species in your area? Do you need a permit? Ensure you’ve covered all the issues by checking the Planning Ahead page.
  • Important: Different threatened species may have different requirements. For any activity you are considering, read the Activity Advice pages for background information and important advice about managing around the needs of multiple threatened species.
  

Habitat

  • ‘Habitat’ refers to both known habitat for the species (i.e. in or near habitat where the species has been recorded) and potential habitat (i.e. areas of habitat with appropriate characteristics for the species and within the species potential range which have not yet been adequately surveyed).
  • If in doubt about whether a site represents potential habitat for this species, contact the Threatened Species Section for further advice.
  • The known range of the Ptunarra Brown Butterfly includes areas above 400 m altitude in the north-west plains, Central Plateau, southern Midlands and eastern highlands. The species does not extend into the lowland plains of the Midlands where it may be too warm for the butterfly and where it is too dry for its food plant to flourish. The potential range of the Ptunarra Brown Butterfly includes all patches of Poa tussock habitat within these areas.
  • Habitat for the Ptunarra Brown Butterfly corresponds to 'Lowland grassland' (above 400 m), 'Highland grassland'  and 'Grassy woodland and forest' in the NRE Bushcare Toolkit. See Grassy Bush in the NRE Bushcare Toolkit for more information on how to manage these vegetation types.
  • Habitat characteristics for the Ptunarra Brown Butterfly includes the following elements: generally above 400 m; habitat must have a significant cover of Poa tussock; the preferred habitat ranges from Poa tussock grassland and sedgeland to grassy shrubland to Eucalyptus grassy woodland.
  • What to avoid

  • conversion of habitat to pasture or plantation
  • overgrazing of habitat
  • over-burning of habitat

Surveying

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Key Survey reliability more info
M Peak survey period
M Potential survey period
M Non-survey period

To ensure you follow the law - check whether your survey requires a permit. Always report any new records to the Natural Values Atlas, or send the information direct to the Threatened Species Section. Refer to the Activity Advice: Surveying page for background information.

Species Spring Summer Autumn Winter
Ptunarra Brown Butterfly S S O O N N D D J J F F M M A A M M J J J J A A

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  • ​The flying season lasts for two to three weeks in early autumn (March), during which period the eggs are laid in tussock grass. Males emerge before females, and butterflies at higher altitudes emerge earlier than those at lower elevations.
  • The species can be surveyed by walking slowly through areas of Poa habitat and observing the butterflies as they flutter around the low tussock and shrub vegetation, often in response to the movement of the observer.

Helping the species

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  • In order to recognise the species if it occurs on your property, learn to identify the Ptunarra Brown Butterfly. If in doubt, seek expert assistance with identification.
  • If you live or work in the area where the species occurs (see distribution map, above), look out for and record any observations of the species. All records of this species can provide important information on distribution and abundance
  • If you are interested in knowing for certain whether the species occurs on your land, organise a formal survey. You may need to employ an ecological consultant to do this. Your local Bushcare or Field Naturalist club may be able to assist you with a survey.
  • Important! Always report any observations of the species to the NRE Natural Values Atlas, or else provide the data direct to the Threatened Species Section. Records stored on the NVA are a permanent record and are accessible to other people interested in this species.
  • Consider the needs of the whole habitat. Preserving a threatened species' habitat is the best way to manage both the species and the environment in which it lives.
  • Habitat for the Ptunarra Brown Butterfly corresponds to 'Lowland grassland' (above 400 m), 'Highland grassland'  and 'Grassy woodland and forest' in the NRE Bushcare Toolkit. See Grassy Bush in the NRE Bushcare Toolkit for more information on how to manage these vegetation types.
  • For long-term protection of populations on private land – consider protection of habitat through a vegetation management agreement or conservation covenant. See the NRE Private Land Conservation Program for more details.

Cutting or clearing trees or vegetation

  • ​The Ptunarra Brown Butterfly is absent from areas which have been converted to pasture. Large areas of this species' native grassland habitat has been lost through agricultural development, and many populations are now found on the fringes of areas which once would have supported large colonies.
  • In the Midlands, over 97% of the original native grasslands and grassy woodlands have been lost through conversion to pasture and cropland.
  • In the Northwest Plains, large areas of Poa dominated grasslands and grassy woodlands, which are naturally restricted in area, have been converted to eucalypt plantation.
  • To prevent further loss of habitat - avoid clearing and conversion of remaining areas of Poa tussock habitat within the species' range.

Stock grazing

  • Grazing intensity affects the abundance of Ptunarra Brown Butterflies but the exact relationship between grazing pressure and butterfly numbers is not fully understood.
  • Few butterflies are found on sites which are heavily grazed but in areas where there has been little or no grazing and where the tussocks have become large and overgrown, butterfly numbers may also be low.
  • Some grazing appears to be beneficial to the butterfly as it tends to keep grasslands open and Poa tussocks healthy. 
  • To prevent degradation and/or loss of habitat - avoid heavy grazing of habitat.
  • To prevent over-growth of tussocks leading to poor quality habitat - manage stock grazing in areas of habitat so as to maintain the cover of Poa and to avoid dense and rank growth of tussocks.
  • For more information on suitable grazing levels in areas of Ptunarra Brown Butterfly habitat, contact the Threatened Species Section.

Burning

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  • ​Repeated burning of remnant native grassland and other grassy habitats has caused a severe decline in abundance of the Ptunarra Brown Butterfly in some areas.
  • However, too infrequent firing promotes invasion of native grassland by shrubby species, reducing the cover of Poa and the attractiveness of the habitat to the butterfly.
  • To prevent degradation and/or loss of habitat - avoid over-burning of habitat.
  • To prevent invasion of habitat by shrubby species leading to poor quality habitat - manage burning in areas of habitat so as to maintain a moderate cover of Poa and to avoid the displacement of Poa tussock grassland by shrubby species.
  • For more information on fire management in areas of Ptunarra Brown Butterfly habitat, contact the Threatened Species Section.

Agriculture

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  • ​The Ptunarra Brown Butterfly is absent from areas which have been converted to pasture. Large areas of this species' native grassland habitat has been lost through conversion to pasture, and many populations are now found on the fringes of areas which once would have supported large colonies.
  • In the Midlands, over 97% of the original native grasslands and grassy woodlands have been lost through conversion to pasture and cropland.
  • To prevent loss of habitat - avoid clearing and conversion of Poa tussock habitat.

Construction

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Subdivision

Earthworks

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Changing water flow / quality

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Use of chemicals

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Recreation

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Further information

​Check also for listing statement or notesheet pdf above (below the species image).

​​Cite as: Threatened Species Section (). (): Species Management Profile for Tasmania's Threatened Species Link. ​ ​Department of Natural Resources and Environment Tasmania. Accessed on .

Contact details: Threatened Species Section, Department of Natural Resources and Environment Tasmania​, GPO Box 44, Hobart, Tasmania, Australia, 7001. Phone (1300 368 550).

Permit: A permit is required under the Tasmanian Threatened Species Protection Act 1995 to 'take' (which includes kill, injure, catch, damage, destroy and collect), keep, trade in or process any specimen or products of a listed species. Additional permits may also be required under other Acts or regulations to take, disturb or interfere with any form of wildlife or its products, (e.g. dens, nests, bones). This may also depend on the tenure of the land and other agreements relating to its management. ​​​​​