Camphor laurel (Cinnamomum camphora) most toxic chemotypes - rejection of key threatening process listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to reject a proposal to list Camphor laurel Cinnamomum camphora most toxic chemotypes as a KEY THREATENING PROCESS in Schedule 3 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. Camphor laurel Cinnamomum camphora is a large evergreen tree native to Southeast Asia which was introduced into Australia following European settlement. It has been widely planted as a street and garden tree and in the Richmond-Tweed region as a shade and windbreak species.

2. Camphor laurel Cinnamomum camphora fruits abundantly in autumn and winter and the fruits are dispersed by birds. Establishment of seedlings occurs widely.

3. Camphor laurel Cinnamomum camphora contains significant amounts of various chemicals known or suspected of being toxic and/or carcinogenic. There is variation between trees in the presence and relative abundance of particular chemicals, allowing recognition of a number of forms, chemotypes, characterised by their chemical composition. The two main chemotypes present in Australia are the 'camphor' and 'cineole' types; the 'camphor' type is considered to be the dominant chemotype in the Northern Rivers region of NSW.

4. Although Camphor laurel Cinnamomum camphora contains toxic chemicals, this is true of many plants. Comparative studies commissioned by the Scientific Committee indicate that native Eucalyptus tereticornis leaf exudates are significantly more toxic (in standardised toxicological tests) than Camphor laurel leachates.

5. Claims have been made that Camphor laurel Cinnamomum camphora is responsible for causing mass bird deaths by poisoning, and that birds (particularly rainforest pigeons), tadpoles, koalas and other native mammals are threatened by toxic chemotypes of Camphor laurel. (It is also claimed that native fish and aquatic invertebrates are threatened, but these taxa are not covered by the Threatened Species Conservation Act).

6. There is a lack of data on the effective concentration of Camphor laurel Cinnamomum camphora exudates and leachates in field situations. There is also no substantiated evidence to support the claims of adverse impacts on native taxa. In the case of some rainforest pigeons, there is evidence that Camphor laurel Cinnamomum camphora fruit may be a major winter food, and that patches of Camphor laurel Cinnamomum camphora provide important stepping stones, linking fragmented rainforest remnants (Date et al. 1989, Date et al. 1991 and 1992).

7. Camphor laurel Cinnamomum camphora is currently a declared noxious weed (Control category W4d) in all or part of the following local control areas, Ballina, Blue Mountains, Byron, Copmanhurst, Grafton Hornsby Ku-ring-gai, Kyogle, Lismore, Maclean, Pristine Waters, Richmond Valley, Ryde, Tweed and Willoughby (NSW Agriculture web site www.agric.nsw.gov.au). The Scientific Committee recognises that invasive Camphor laurel Cinnamomum camphora poses major land and resources management issues, and that this categorisation is appropriate.

8. The Scientific Committee is of the opinion that, at this time, there is no evidence that Camphor Laurel Cinnamomum camphora through toxic exudates and leachates poses a demonstrable threat to two or more listed species, populations or endangered ecological communities, or is likely to cause species, populations or ecological communities to become threatened.

9. In view of the above the Scientific Committee is of the opinion that Camphor laurel Cinnamomum camphora most toxic chemotypes is not eligible to be listed as a Key Threatening Process in Schedule 3 of the Act.

Associate Professor Paul Adam
Chairperson
Scientific Committee

Proposed Gazettal date: 23/04/04
Exhibition period: 23/04/04 - 04/06/04

References

Date EM, Recher HF (1989) Ecology and management of rainforest pigeons in New South Wales. Report to the NSW National Parks and Wildlife Service, Sydney.

Date EM, Ford hectares, Recher HF (1991) Frugivorous pigeons, stepping stones, and weeds in northern New South Wales. In: Nature Conservation 2: the Role of Corridors. Saunders, D.A. and Hobbs, R.J. (Eds). Surrey Beatty and Sons, Chipping Norton, Sydney, pp. 241-245.

Date EM, Recher, HF Ford H (1992) Status of Rainforest Pigeons in Northern New South Wales. Report to NSW National Parks and Wildlife Service, Sydney.