Elatostema montanum (Mountain Procris, a herb)

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)

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

Elatostema montanum (Mountain Procris, a herb)

2. National context

This species is endemic to Norfolk Island and not currently listed under the EPBC Act or State legislation.

3. How judged by TSSC in relation to the 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

Since European settlement 80% of the native vegetation on Norfolk Island has been cleared. A significant decline in population numbers is inferred due to the extensive land clearing, unrestricted grazing and significant habitat degradation. There has been widespread establishment of large populations of invasive weed species and high levels of seed predation by rats. Whilst it is possible that the population decline since European settlement could be as high as 80%, there is, however, a lack of information about generation times and no quantitative data is available for recent rates of decline.

Therefore, the species is not eligible for listing under this criterion.

Criterion 2 - Geographic distribution

The species is very restricted in its geographic distribution, the extent of occurrence being 0.399km2. The species is considered to be severely fragmented, being recorded from a total of seven sites, only two sites containing more than 6 individuals and none containing more than 26. Since surveys undertaken in 1984 some populations have been destroyed by cattle grazing. Their occurrence in the drainage lines of steeply undulating terrain makes them susceptible to flood damage. Continuing declines in the number of mature individuals, extent of occurrence, area of occupancy, and quality of habitat are projected due to the vulnerability of small populations to stochastic disturbance events (eg cyclones) and ongoing competition with weeds such as Lantana camara and Ageratina riparia. The species is adapted to moist forest conditions and is therefore susceptible to unfavourable climate change (projected increases in the incidence of drought and extreme rainfall events that cause physical damage).

Therefore, the species is eligible for listing as critically endangered under this criterion.

Criterion 3 - Population size and decline in numbers or distribution

The population is estimated to number 76 individuals located in seven populations that are considered to be severely fragmented as no population contains more than 26 individuals and only two populations contain more than 6 individuals. Continuing declines (not quantified) in the number of mature individuals are projected due to the vulnerability of small populations to stochastic disturbance events (eg. cyclones) and ongoing competition with weeds such as Lantana camara and Ageratina riparia. The species is adapted to moist forest conditions and is therefore susceptible to unfavourable climate change (projected increases in the incidence of drought and extreme rainfall events that cause physical damage).

Therefore, the species is eligible for listing as critically endangered under this criterion.

Criterion 4 - Population size

The number of mature individuals is very low, the total population being 76 plants.

Therefore, the species is eligible for listing as endangered under this criterion.

Criterion 5 - Probability of extinction in the wild

There is no quantitative data available against this criterion.

4. Conclusion

The species is very restricted in its geographic distribution, the extent of occurrence being 0.399km2. The total population comprises 76 individuals and is considered to be severely fragmented, being recorded from a total of seven sites, only two sites containing more than 6 individuals and none containing more than 26. Continuing declines in the number of mature individuals, extent of occurrence, area of occupancy, and quality of habitat are projected due to the vulnerability of small populations to stochastic disturbance events (eg. cyclones) and ongoing competition with weeds. The species is adapted to moist forest conditions and is therefore susceptible to unfavourable climate change (projected increases in the incidence of drought and extreme rainfall events that cause physical damage). The species is eligible for listing as critically endangered under criteria 2 and 3.

5. 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: Elatostema montanum (Mountain Procris, a herb)