Eucalyptus largeana - endangered species listing

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the tree Eucalyptus largeana Blakely & Beuzev. as an ENDANGERED SPECIES in Part 1 of Schedule 1 of the Act. Listing of Endangered species is provided for by Part 2 of the Act.

NSW Scientific Committee - final determination

The Scientific Committee has found that:

1. Eucalyptus largeana Blakely & Beuzev. (family Myrtaceae), also known as Craven Grey Box, is described by Hill (1991) as follows: “Tree to 40 m high; bark persistent on trunk and larger branches, grey with whitish patches, fibrous-flaky (`box'), smooth above, white to grey, shedding in short ribbons. Juvenile leaves disjunct, lanceolate to broad-lanceolate, dull dark green. Adult leaves disjunct, narrow-lanceolate, 12–18 cm long, 1–2 cm wide, dark green, dull, concolorous. Conflorescence compound; umbellasters 7-flowered; peduncle terete or 4-angled, 10–15 mm long; pedicels terete, 2–4 mm long. Buds ovoid, 3–5 mm long, 2–3 mm diam., scar present; calyptra hemispherical or conical, shorter than and as wide as hypanthium. All stamens fertile. Fruit pyriform or ovoid, 3–4 mm long, 2–3 mm diam.; disc depressed; valves enclosed.”

2. Eucalyptus largeana is restricted to the NSW North Coast Botanical subdivision (Hill 1991, Royal Botanic Gardens and Domain Trust 1999-2011), within the NSW North Coast Bioregion, sensu Thackway and Cresswell (1995). A number of unsubstantiated records exist from outside the currently accepted range, including from the NSW Northern Tablelands Botanical subdivision and Central Western Slopes Botanical subdivision, however these records have not been verified with voucher specimens.

3. Fourteen populations represented by voucher specimens collected less than 50 years ago and/or confirmed during targeted field surveys are believed to be extant (Mackenzie 2011, unpubl. data). Ten populations which have not been sighted in more than 50 years are presumed extinct. Four of these populations could not be relocated during recent (2007) targeted field surveys (Fawcett pers comm. 2008). It is possible that the species still persists in these areas in very low numbers. A further 18 populations recorded during vegetation surveys, but unsubstantiated with voucher specimens, remain unconfirmed, including nine populations reported from outside the currently accepted range of the species and best regarded as doubtful until substantiated with voucher specimens (Mackenzie 2011).

4. The extent of occurrence (EOO) is approximately 5,000-10,000 km2 based on exclusion and inclusion, respectively, of unconfirmed records from within the species’ currently accepted range (Mackenzie 2011), and using a minimum convex polygon as recommended by IUCN (2010). The area of occupancy (AOO) is 120-140 km2 based on exclusion and inclusion, respectively, of unconfirmed records within the species’ currently accepted range (Mackenzie 2011), using 2 x 2 km grid cells, the scale recommended for assessing area of occupancy by the IUCN (2010). Hence, the geographic distribution is considered to be highly restricted.

5. The geographic distribution of Eucalyptus largeana has been reduced as a result of land clearing, particularly on private property between Pokolbin and Dungog. Only a small number of the known sites targeted during recent (2007) field surveys had extant individuals. In the southern part of the species’ range individuals could not be located at the majority of previously recorded sites. The EOO is estimated to have declined by 31-66% based on the inclusion and exclusion, respectively, of unconfirmed records from within the species’ currently accepted range (Mackenzie 2011). The AOO is estimated to have declined by 31- 36% based on the inclusion and exclusion, respectively, of unconfirmed records from within the species’ currently accepted range (Mackenzie 2011). This is indicative of a moderate to large reduction in population size.

6. The largest known population of the species is in Copeland Tops State Conservation Area where the estimated population size is likely to be in excess of 3,300-6,700 individuals (Mackenzie 2011). Approximately 50 individuals have been confirmed within Avon River State Forest plus approximately 70 individuals outside this State Forest boundary. A number of scattered individuals have been reported from within Glen Nature Reserve (Eastcoast Flora Survey 2009), however, these records remain unconfirmed. With the exception of these three populations, the known extant populations are small and isolated, comprising individual trees or small clumps of trees with little probability of re-colonization in the event of local extinction, particularly in the southern part of the species’ range. Hence, the number of mature individuals in the species is likely to be moderately low and nearly all mature individuals are observed or inferred to occur within a small number of populations or locations.

7. Very few populations of Eucalyptus largeana are reserved or occur on land managed for conservation. Populations are known from Copeland Tops State Conservation Area and Berrico Nature Reserve, with unconfirmed records from Talawahl and Glen Nature Reserves and Willi Willi National Park. The majority of remaining populations occur on private lands and roadsides, often as single trees or small clumps interspersed with other tree species. Populations occurring on private land continue to be threatened by clearing and inappropriate management. 'Clearing of native vegetation' is listed as a Key Threatening Process under the NSW  Threatened Species Conservation Act 1995. With the exception of Copeland Tops State Conservation Area, populations of  Eucalyptus largeana are threatened by demographic and environmental stochasticity due to their small size and restricted distribution. Collectively, these threats are indicative of a continuing decline in population size, geographic distribution, and in area, extent and quality of habitat.

8. Eucalyptus largeana is not eligible to be listed as a Critically Endangered species.

9. Eucalyptus largeana Blakely & Beuzev. is eligible to be listed as an Endangered species as, in the opinion of the Scientific Committee, it is facing a very high risk of extinction in New South Wales in the near future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2010:

Clause 7 Restricted geographic distribution and other conditions

The geographic distribution of the species is estimated or inferred to be:

(b) highly restricted,

and:

(d) a projected or continuing decline is observed, estimated or inferred in either of the key indicators:

(a) an index of abundance appropriate to the taxon, or

(b) the geographic distribution, habitat quality or diversity, or genetic diversity of the species.

Associate Professor Michelle Leishman
Chairperson
Scientific Committee

Gazetted 16/11/12

References:

Eastcoast Flora Survey (2009) ‘Validation of Vegetation Mapping: The Glen Nature Reserve, Lower North Coast, NSW.’ Unpublished report to NPWS Barrington Tops Area.

Hill K (1991) Eucalyptus largeana. In: ‘Flora of New South Wales’ Vol. 2 (Ed. GJ Harden) p. 115. (University of NSW Press, Kensington)

IUCN Standards and Petitions Subcommittee (2010) ‘Guidelines for Using the IUCN Red List Categories and Criteria Version 8.1.’ Prepared by the Standards and Petitions Subcommittee in March 2010.

Mackenzie B (2011) ‘Current conservation status of Craven Grey Box Eucalyptus largeana Blakely & Beuzev. in NSW.’ Report to the NSW Scientific Committee.

Royal Botanic Gardens and Domain Trust (1999-2011) PlantNET - The PlantInformation Network System of The Royal Botanic Gardens and Domain Trust, Sydney, Australia (version 2.0). Accessed on 2nd May 2012.

Thackway R, Cresswell ID (1995) An interim biogeographic regionalisation for Australia: a framework for setting priorities in the National Reserve System Cooperative Program. (Version 4.0. ANCA: Canberra.)