Long-nosed bandicoot population, North Head - endangered population listing

NSW Scientific Committee - final determination



The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the North Head population of the Long-nosed Bandicoot, Perameles nasuta, Geoffrey 1804, as an Endangered Population on Part 2 of Schedule 1 of the Act. The distribution of the population is defined on the map which forms part of this Final Determination.

Any submissions received following advertisement of the Preliminary Determination have been considered by the Scientific Committee.

Listing of Endangered Populations is allowed for by Section 11 of the Act.

The Scientific Committee has found that:

1. Perameles nasuta is not listed on Part 1 of Schedule 1 of the Act and thus populations of P. nasuta are eligible for consideration for inclusion on Part 2 of Schedule 1 of the Act.

2. P. nasuta has been reliably reported as occurring on North Head, within the area defined on the accompanying map.

3. The population of P. nasuta at North Head is estimated to be about one hundred animals, with fluctuations around this number over time.

4. The Scientific Committee is of the opinion that the effective population size is much less than the census population, and that, on the basis of the scientific literature the best available estimate of the effective population size would be approximately 10-11% of the census population.

5. There is evidence that one cause of mortality of P. nasuta at North Head is as a result of attacks by introduced predators (foxes, dogs, cats). Road kills have also been reported.

6. P. nasuta was once widespread in the Sydney region but many formerly recorded populations have become extinct. The North Head population is now isolated and disjunct. The nearest surviving population to that at North Head known to the Committee is in Pittwater Local Government Area.

7. Population genetic theory would suggest that a population as small as that of the North Head P. nasuta population would suffer effects of inbreeding depression and loss of genetic variation, affecting population viability.

8. In addition to genetic consequences of small population size, a small population occupying a limited, discrete area is at risk from stochastic disturbance events.

9. In light of the above, and taking into account discussion in relevant international scientific literature, the Scientific Committee is of the opinion that the North Head population of P. nasuta is in immediate danger of extinction.

10. While the North Head population of P. nasuta is disjunct it is not situated at or near the limit of the geographic range of the species.

11. The Committee is not aware of any genetic studies of the North Head P. nasuta population. However, the effects of fragmentation and isolation may result in local populations possessing distinct genetic features. There is thus a likelihood that the population may be genetically distinct.

12. The Scientific Committee is of the opinion that the North Head P. nasuta population is of significant conservation value on the grounds that it is:

  • a disjunct population
  • one of the few surviving populations within the Sydney region
  • a population which has been the subject of a number of scientific studies, and is thus an important reference population
  • accorded considerable value by the local community, and thus serves to promote conservation more generally,
13. As a consequence of points 1, 9, 11 and 12 above the Scientific Committee is of the opinion that the criteria specified in Section 11 of the Act are met and that the North Head Population of P. nasuta should be listed as an Endangered Population on Part 2 of Schedule 1 of the Threatened Species Conservation Act.


Dr Chris Dickman

Chairperson

Scientific Committee

Gazetted: 28/2/97


Map accompanying the final determination for the North Head population of the long-nosed bandicoot.

About the NSW Scientific Committee

Page last updated: 28 February 2011