Pittwater spotted gum forest - endangered ecological community listing

NSW Scientific Committee - final determination

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the Pittwater Spotted Gum Forest in the Sydney Basin Bioregion as an ENDANGERED ECOLOGICAL COMMUNITY on Part 3 of Schedule 1 of the Act. Listing of Endangered Ecological Communities is provided for by Part 2 of the Act.

The Scientific Committee has found that:

1. The Pittwater Spotted Gum Forest is the name given to the plant community that is characterised by the following assemblage of species:

  • Acacia floribunda
  • Acrotriche divaricata
  • Adiantum aethiopicum
  • Allocasuarina litoralis
  • Allocasuarina torulosa
  • Angophora costata
  • Angophora floribunda
  • Billardiera scandens
  • Breynia oblongifolia
  • Cassytha paniculata
  • Cayratia clematidea
  • Cissus hypoglauca
  • Corymbia gummifera
  • Corymbia maculata
  • Dianella caerulea
  • Dodonaea triquetra
  • Doodia caudata
  • Eleocarpus reticulatis
  • Entolasia stricta
  • Eucalyptus botryoides
  • Eucalyptus paniculata
  • Eucalytpus punctata
  • Eucalyptus umbra
  • Eustrephus latifolius
  • Geitonoplesium cymosum
  • Glochidion ferdinandi
  • Gymnostachys anceps
  • Hakea sericea
  • Hydrocotyle peduncularis
  • Livistona australis
  • Lomandra longifolia
  • Macrozamia communis
  • Notelaea longifolia
  • Oxylobium ilicifolium
  • Pandorea pandorana
  • Pittosporum undulatum
  • Platylobium formosum
  • Pseuderanthemum variabile
  • Pteridium esculentum
  • Pultenaea flexilis
  • Syncarpia glomulifera
  • Synoum glandulosum
  • Themeda australis
  • Xanthorrhoea macronema
2. The total species list of the community is larger than that given above, with many species present only in one or two sites or in very small quantity. In any particular site not all of the assemblage listed may be present at any one time (at least above ground), seeds of more species may be present in the soil seed bank. The species composition of a site will be influenced by the size of the site and by its recent disturbance history. For a number of years after a major disturbance, dominance by a few species may occur, with gradual restoration of a more complex composition and vegetation structure over time. The balance between species will change over the fire cycle, and may also change in response to changes in fire frequency.

3. The Pittwater Spotted Gum Forest occurs on shale-derived soils with high rainfall on lower hillslopes on the Narrabeen group - Newport Formation, on the Barrenjoey Peninsula and western Pittwater foreshores.

4. The structure of the community was originally open-forest but may now exist as woodland or as remnant trees.

5. Characteristic tree species are Corymbia maculata and Eucalyptus paniculata, associated trees include Angophora costata, Corymbia gummifera, Eucalyptus umbra, Eucalyptus punctata, Syncarpia glomulifera, Eucalyptus botryoides, Angophora floribunda.

6. Pittwater Spotted Gum Forest has been reported from the Local Government Area of Pittwater. The area is within the County of Cumberland entirely within the Sydney Basin Bioregion.

7. Pittwater Spotted Gum Forest is referred to in Benson & Howell 1990, and described in Map Unit 9g (ii) in Benson & Howell 1994.

8. Adjacent communities on sandstone soils are generally part of the Sydney Sandstone Complex (see Benson & Howell 1990).

9. Pittwater Spotted Gum Forest has been extensively cleared from the Barrenjoey Peninsula and the western and southern shores of Pittwater, and is threatened by further clearing for housing and related infrastructure, and for fire mitigation. Remnants are also threatened by weed invasion especially Lantana camara and Acacia saligna and by inappropriate fire regimes.

10. Only tiny remnants on western Pittwater are included within Ku-Ring-Gai Chase National Park The major remnants on the Peninsula are within Pittwater Council reserves, McKay Reserve, Angophora Reserve and Stapleton Park.

11. In view of the small size of existing remnants, the threat of further clearing and other known threats (listed in 9), the Scientific Committee is of the opinion that the Pittwater Spotted Gum Forest in the Sydney Basin Bioregion is likely to become extinct in nature in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate and that the community is eligible for listing as an endangered ecological community.

References

Benson, D. and Howell, J., 1990, Taken for Granted: The bushland of Sydney and its suburbs, Kangaroo Press, Kenthurst.

Benson, D. and Howell, J. (1994) The natural vegetation of the Sydney 1:100 000 Map Sheet. Cunninghamia 3(4):677-787.

Proposed Gazettal date: 18/12/98

Exhibition period: 18/12/98 - 29/1/99


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Page last updated: 28 February 2011