Prasophyllum sp. Majors Creek (Jones 11084) - critically endangered species listing
The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the orchid Prasophyllum sp. Majors Creek (Jones 11084) as a CRITICALLY ENDANGERED SPECIES in Part 1 of Schedule 1A of the Act, and as a consequence, to omit reference to Prasophyllum sp. Majors Creek (Jones 11084) from Part 1 of Schedule 1 (Endangered species) of the Act. Listing of Critically Endangered species is provided for by Part 2 of the Act.
NSW Scientific Committee - final determination
The Scientific Committee has found that:
1. Prasophyllum sp. Majors Creek (Jones 11084) (family Orchidaceae) is an undescribed orchid previously included with P. caricetum D. L. Jones, but now considered distinct from this species. Prasophyllum caricetum has been described by Jones (2000, 2006). Prasophyllum sp. Majors Creek differs from P. caricetum by having smaller flowers, incurved petals, a smaller and narrower labellum, a smaller and narrower labellum callus, a narrower column, a narrower anther, curved column wings, and a very narrow hamulus on the pollinarium. Additionally, it grows in a grassy montane habitat whereas P. caricetum grows in moist to wet, sedge-rich montane swamps.
2. Prasophyllum sp. Majors Creek is known from a single, unreserved population near Majors Creek, approximately 70 km south-east of Canberra. It is likely that the species was once more widespread before its discovery in 1992, however extensive clearing and fragmentation of native vegetation in the Majors Creek district is likely to have markedly reduced suitable habitat (Copeland 2008). The habitat at the known site is a grassland dominated by Themeda australis on a moist brown loamy soil (D. Rouse pers. comm.).
3. The extent of occurrence and area of occupancy of Prasophyllum sp. Majors Creek, are estimated (Copeland 2008) to be no greater than 4 km2, based on 2 x 2 km grid cells, the scale recommended for assessing areas of occupancy by IUCN (2008).
4. Approximately 10 plants were observed in 1992 and 1994 when Prasophyllum sp. Majors Creek was flowering (D. Jones pers. comm.). Despite numerous searches of the site and the surrounding areas, no plants have been observed for approximately 13 years (D. Jones pers. comm., D. Rouse pers. comm., R. Rehwinkel pers. comm.). The species may now be extinct although the variability in flowering patterns of many species of Prasophyllum suggests a possibility that some plants may still exist as dormant underground tubers.
5. Prasophyllum sp. Majors Creek is threatened by environmental and demographic stochasticity due to its very highly restricted range and extremely low number of mature individuals. Earthworks at the site in 1995 may have potentially contributed to the decline of Prasophyllum sp. Majors Creek, together with mowing, slashing, trampling and illegal collection by visitors (Copeland 2008).
6. The threats to Prasophyllum sp. Majors Creek described above indicate the species is undergoing a continuing decline, or likely to undergo a future decline in abundance, and in habitat area and quality. However, the species may have already declined to extinction.
7. Prasophyllum sp. Majors Creek (Jones 11084) is eligible to be listed as a Critically Endangered species as, in the opinion of the Scientific Committee, it is facing an extremely high risk of extinction in New South Wales in the immediate future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2002:
Clause 14
The species has undergone, is observed, estimated, inferred or reasonably suspected to have undergone or is likely to undergo within a time frame appropriate to the life cycle and habitat characteristics of the taxon:
(a) a very large reduction in population size,
based on:
(d) an index of abundance appropriate to the taxon,
(e) geographic distribution, habitat quality or diversity, or genetic diversity.
Clause 15
The geographic distribution of the species is estimated or inferred to be:
(a) very highly restricted,
and:
(d) a projected or continuing decline is observed, estimated or inferred in either:
(i) an index of abundance appropriate to the taxon,
(ii) geographic distribution, habitat quality or diversity, or genetic diversity;
(e) the following conditions apply:
(i) the population or habitat is observed or inferred to be severely fragmented;
(ii) all or nearly all mature individuals are observed or inferred to occur within a small number of populations or locations.
Clause 16
The estimated total number of mature individuals of the species is:
(a) very low,
and:
(d) a projected or continuing decline is observed, estimated or inferred in either:
(i) an index of abundance appropriate to the taxon,
(ii) geographic distribution, habitat quality or diversity, or genetic diversity;
(e) the following conditions apply:
(i) the population or habitat is observed or inferred to be severely fragmented;
(ii) all or nearly all mature individuals are observed or inferred to occur within a small number of populations or locations.
Clause 17
The total number of mature individuals of the species is observed, estimated or inferred to be:
(a) extremely low.
Dr Richard Major
Chairperson
Scientific Committee
Proposed Gazettal date: 18/12/09
Exhibition period: 18/12/09 – 05/03/10
References:
Copeland, L. (2008) Conservation status of Prasophyllum sp. Majors Creek (Jones 11084) (Orchidaceae) in New South Wales. Report to the NSW Scientific Committee.
Jones, D.L. (2000) Ten new species of Prasophyllum R.Br. (Orchidaceae) from south-eastern Australia. The Orchadian 13, 148-173.
Jones, D.L. (2006) A Complete Guide to Native Orchids of Australia including the Island Territories. (Reed New Holland: Sydney).
IUCN (2008) ‘Guidelines for using the IUCN Red List Categories and Criteria. Version 7.0.’ (Standards and Petitions Working Group of the IUCN Species Survival Commission Biodiversity Assessments Sub-committee: Switzerland).