Persoonia pauciflora (North Rothbury Persoonia)

Advice to the Minister for the Environment and Heritage from the Threatened Species Scientific Committee (TSSC) on Amendments to the list of Threatened Species under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act)
8 July 2005

1. Scientific name, common name (where appropriate), major taxon group

Persoonia pauciflora (North Rothbury Persoonia)

2. Description

The North Rothbury Persoonia (Persoonia pauciflora) is a small spreading shrub, around 0.1-1.4 m high and 0.4-2 m wide. It has bright green needle like leaves which are moderately hairy when immature. The North Rothbury Persoonia closely resembles P. isophylla and to a lesser extent P. pinifolia, but can be distinguished by its fewer flowers and shorter flowering period (Weston 1999). The North Rothbury Persoonia occurs in dry open-forest or woodland habitats, generally with a grassy understorey (Patrick 1999).

3. National context

The North Rothbury Persoonia was first discovered in 1997 in a highly disturbed and fragmented area just south of North Rothbury in the Lower Hunter Valley, New South Wales (Weston 1999). Subsequent surveys for the species in the Lower Hunter Valley have been undertaken since 1997 however, the species known range is still restricted to the North Rothbury area. The majority of this species occurs on private land with approximately 10% of the population occuring on roadsides owned by the local Council.

It is currently listed as endangered under the Threatened Species Conservation Act 1995 in New South Wales. It is not listed under the EPBC Act.

EPBC Act criteria.

TSSC judges the species to be eligible for listing as critically endangered under the EPBC Act. The justification against the criteria is as follows:

Criterion 1 - Decline in numbers

The North Rothbury Persoonia has been the subject of a number of surveys over the past ten years. Surveys conducted between 1997 and 2001 showed a gradual increase in the total number of individuals attributed to increased survey effort, high rainfall and the removal of cattle grazing in some areas. A more recent survey however, has shown that the number of individuals has declined from 350 mature individuals in 2001 to between 80 - 125 mature individuals in 2003 (G. Patrick 2004, pers. comm.). This represents a 64-77% decline over a three year period or a severe reduction in numbers. The reason for the decline is attributed to changes in landuse practices arising from the rezoning for subdivision and subsequent development of what was originally rural land used primarily for grazing. The rezoning and subdivision commenced around the time the decline in the numbers of the North Rothbury Persoonia become evident.

The land parcel where the majority of the population of North Rothbury Persoonia is located has been approved for subdivision. One subpopulation is located in a land zoned for subdivision into minimum land parcel size of 40 000 m2, the remaining two subpopulations occur in land zoned for subdivision into minimum land parcel sizes of 4000 m2 (Cessnock City Council 1989). Subdivision and development will reduce the area of suitable habitat for the species and contribute to an ongoing reduction in numbers. The rezoning for subdivision and development is identified as the main ongoing threat to the survival of this species.

This species has undergone a severe decline in numbers of between 64-77% in the recent past. It is likely to be subject to a further decline in numbers in the future. Therefore, the species is eligible for listing as endangered under this criterion.

Criterion 2 - Geographic distribution

The North Rothbury Persoonia's geographic distribution is considered precarious for the survival of the species and is very restricted. The North Rothbury Persoonia has an extent of occurrence of 4.5 km2 and area of occupancy of 0.35 km2. The species distribution is fragmented and it occurs at 3 locations which comprise approximately 90% of the total number of individuals (Patrick 2001). The remainder of the population occurs as scattered individuals or in small isolated groups. The distance between each subpopulation is between 450 m to 750 m and the approximate number of mature individuals in each subpopulation is between 15 to 50 (G. Patrick 2004, pers.comm.).

Surveys conducted between 1997 and 2001 showed a gradual increase in the total number of individuals attributed to increased survey effort, high rainfall and the removal of cattle grazing in some areas. A more recent survey however, has shown that the number of individuals has declined from 350 mature individuals in 2001 to between 80 - 125 mature individuals in 2003 (G. Patrick 2004, pers. comm.). This represents a 64-77% decline over a three year period. Subdivision and development of the area is considered to be the main cause of decline and since subdivision is continuing to occur, it is inferred that there will be a continual decline in mature individuals of this species in the North Rothbury area.

The North Rothbury Persoonia has a very restricted geographic distribution. There has been a decline in numbers in the recent past and continuing decline is inferred as the threats continue. Its geographic distribution is therefore considered to be precarious for the survival of the species. Therefore, the species is eligible for listing as endangered under this criterion.

Criterion 3 - Population size and decline in numbers or distribution

The estimated total number of mature individuals of North Rothbury Persoonia in 2003 was between 80 - 125 mature individuals. It is located at 3 locations 450 m to 750 m apart with each subpopulation containing no more then 50 mature individuals (G. Patrick 2004, pers. comm.).

Recent surveys have indicated a decline in numbers (see criterion 1). The number is likely to continue to decline as the rezoning, subdivision and development of land continues. This will lead to a probable decrease in the number of mature individuals.

The number of mature individuals of North Rothbury Persoonia is very low and consists of three small subpopulations. The continuing decline due to subdivision of the only areas where this species occurs make its geographic distribution precarious for its survival. Therefore, the species is eligible for listing as critically endangered under this criterion.

Criterion 4 - Population size

The North Rothbury Persoonia occurs at 3 locations within the North Rothbury area of New South Wales. The current estimated total number of mature individuals is 80 - 125.

The estimated total number of mature North Rothbury Persoonia individuals is very low. Therefore, the species is eligible for listing as endangered under this criterion.

Criterion 5 - Probability of extinction in the wild

Although there has been no quantitative analysis of the probablities of extinction in the wild, the very low numbers of plants, the extremely restricted distribution of the species, the 64-77% decline over a three year period and the extreme ongoing risk of losing the remaining individuals due to subdivision and development of its only known location indicates the North Rothbury Persoonia could become extinct in the wild. Therefore, the species is eligible for listing as vulnerable under this criterion.

5. Conclusion

The North Rothbury Persoonia's geographic distribution is precarious for the survival of the species as it is very restricted and subject to ongoing threat. The species has a known extent of occurrence of 4.5 km2 and area of occupancy of 0.35 km2 and the estimated total number of mature individuals is very low with a current estimate of between 80 to 125 mature individuals. Recent changes in landuse arising from the rezoning and subsequent development of rural land is considered to be the main threat to the survival of this species.

The species is eligible for listing as endangered under criteria 1, 2 and 4, is eligible for listing as critically endangered under criterion 3, and is eligible for listing as vulnerable under criterion 5.

6. Recommendation

TSSC recommends that the list referred to in section 178 of the EPBC Act be amended by including in the list in the critically endangered category:

Persoonia pauciflora (North Rothbury Persoonia)

Publications used to assess the nomination

Bernhardt P., and P.H. Weston (1996). The pollination ecology of Persoonia (Proteaceae) in eastern Australia. Telopea 6(4):775-804.

Cessnock City Council (1989). Cessnock Local Environmental Plan 1989, updated May 2004.

Patrick G. (1999). Initial flora survey to sample potential habitat: abundance and distribution of the new plant species Persoonia 'North Rothbury'. Report prepared for the NPWS, Hurstville.

Patrick G. (2000). Survey for the threatened plant species Persoonia pauciflora within the northern and central portions of Cessnock City Council area, 2000. Unpublished report. NSW NPWS, Hurstiville.

Patrick G. (2001). Brief overview on the expansion of populations of the rare plant, Persoonia pauciflora, in the North Rothbury area. Unpublished report. NSW NPWS Hurstville.

Patrick G. Personal communication. 6 August 2004.

Weston P.H. (1999). Persoonia pauciflora (Proteacea), a new species from the Hunter Valley, New South Wales. Telopea 8(2):159-164.

Conservation advice

The North Rothbury Persoonia is a small spreading shrub restricted to a highly disturbed and fragmented area just south of North Rothbury in the Lower Hunter Valley, New South Wales (Hunter/Central Rivers NHT region). The species distribution is fragmented occurring in 3 locations and with only 80 - 125 mature individuals. The area the species occurs in is subject to subdivision and development.

The priority recovery and threat abatement actions required for this species are:

  • protect all known populations of the species, through fencing of known sites and conservation agreements, and raise awareness of the presence of this species and its conservation status with the relevant Council, developer or landholder;
  • monitor the condition and health of all known populations;
  • investigate possible techniques for propagating the species and establishing additional populations in suitable locations.

This list does not encompass all actions that may be of benefit to this species, but highlights those that are considered to be of the highest priority at the time of listing.

New South Wales has not yet developed a recovery plan for this species.

Priority for the development of recovery plan: High