Corymbia trachyphloia-Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion - rejection of endangered ecological community listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to reject a proposal to list the Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion as an ENDANGERED ECOLOGICAL COMMUNITY in Part 3 of Schedule 1 of the Act. Rejection of nominations is provided for by Part 2 of the Act.

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion is the name given to the ecological community characterised by the species assemblage listed in paragraph 2. In NSW all sites are within the Bioregion.

2. The Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion is an open woodland characterised by the following species.

3. The total species list of the community is considerably larger than that given above, with many species present in only one or two sites or in very small quantity. The species composition of a site will be influenced by the size of the site, recent rainfall or drought condition and by its disturbance (including fire) history. The number of species, and the above ground relative abundance of species will change with time since fire, and may also change in response to changes in fire regime (including changes in fire frequency). At any one time, above ground individuals of some species may be absent, but the species may be represented below ground in the soil seed banks or as dormant structures such as bulbs, corms, rhizomes, rootstocks or lignotubers. The list of species given above is of vascular plant species; the community also includes micro-organisms, fungi, cryptogamic plants and a diverse fauna, both vertebrate and invertebrate. These components of the community are poorly documented.

4. The distinctive feature of Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion is the co-occurrence of  Corymbia  trachyphloia, which is uncommon on the NSW North Coast, and  Eucalyptus psammitica. Occurrences of  E. psammitica, E. pyrocarpa and  E. baileyana, but where  C.  trachyphloia is absent, are widespread in the NSW North Coast Bioregion and are not part of the  Corymbia trachyphloia–Eucalyptus psammitica Ecological Community. The  Corymbia trachyphloia–Eucalyptus psammitica Ecological Community has a restricted distribution and is currently only known from the Coutts Crossing area and has been recorded from the Chambigne, Koukandowie and Tallawudjah Nature Reserves and adjoining freehold and Crown lands, but may occur elsewhere in the bioregion (Greenloaning Biostudies Pty Ltd. 2003).

5. Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion is apparently limited to the Glenreagh-Coaldale sandstone group and occurs on a series of steepsided flat-topped ridges west of Coutts Crossing. The community is a sparse open woodland with a canopy of up to 18 metres tall, on shallow infertile sandy soil. The ridge tops are limited in extent. The extent of occurrence of the community is likely to be less than 200 km2 (Mackenzie 2009), making the community highly restricted.

6. Several threats have been identified in parts of the range of the community. These include environmental stochasticity, fragmentation and the risk of weed invasion (NSW Scientific Committee 2003), inappropriate fire and localised weed invasion, clearing for road construction and presence of the pathogen Phytophthora  cinnamomi (Edwards  in litt., MacKenzie 2009). However, the nature and extent of the observed threats are such that they do not operate across the distribution of the community.

7. The Scientific Committee made a Preliminary Determination to support a proposal to list the Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion as an Endangered Ecological Community (NSW Scientific Committee 2003). This preliminary assessment of the community led to the submission of additional information as to the extent and threats to the nominated community. In the light of this information, the Committee has determined that there is currently insufficient evidence to conclude that there is likely to be a decline in this community across its range or a significant part thereof, based on current known threats. Should information arise suggesting that there are significant threats across the range of the community a re-assessment of its conservation status would be warranted.

8. In view of the above the Scientific Committee is of the opinion that Corymbia trachyphloia–Eucalyptus psammitica Ecological Community in the NSW North Coast Bioregion does not currently meet any of the criteria for listing of ecological communities under the  Threatened Species Conservation Regulation 2002 and hence, is not currently eligible to be listed as an Endangered Ecological Community in Part 3 of Schedule 1 of the Act.

Dr Richard Major
Chairperson
Scientific CommitteeProposed

Gazettal date: 26/03/10
Exhibition period: 26/03/10 – 21/05/10

References:

Greenloaning Biostudies Pty Ltd. (2003) Distribution and status of Corymbia trachyphloia / Eucalyptus psammitica ecological community. Unpublished report, Department of Commerce.

Mackenzie B (2009) Corymbia trachyphloia – Eucalyptus psammatica ecological community in the NSW North Coast Bioregion: a short report to the NSW Scientific Committee.

NSW Scientific Committee (2003) Corymbia trachyphloia-Eucalyptus psammitica ecological community in the NSW North Coast Bioregion - proposed endangered ecological community listing.