Threatened species & ecological communities

Baudin's Sea-lavender (Limonium baudinii)

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)
13 April 2005

Contents

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

Limonium baudinii (Baudin's Sea-lavender)

Baudin's Sea-lavender was previously thought to be synonymous with L. australe. Further investigation has recently been undertaken to determine whether or not L.baudinii is worthy of recognition as a distinct taxon (Schahinger 2004). It is noted that the distinguishing feature of L.baudinii, the calyx character, is consistent, and that Limonium baudinii is a biological entity eligible for recognition as a species under the Environment Protection and Biodiversity Conservation Act 1999.

2. Description

Baudin's Sea-lavender is a perennial shrub in the plumbago family. It occurs only in salt marsh habitat close to or below the high water mark near Triabunna, on Tasmania's central east coast.

3. National context

Limonium baudinii is known from three populations in the Spring Bay area of Tasmania's central east coast, occuring immediately adjacent to the town of Triabunna, and only in salt marsh habitat close to or below the high water mark (e.g. the intertidal habitat).

Limonium baudinii is not known to occur in any conservation reserve. Most plants occur on crown land, with one known occurrence of Limonium baudinii on private property at Bogan/Alma Creeks.

The Tasmanian Threatened Species Scientific Advisory Committee has made a preliminary recommendation to list the species "Limonium baudinii" as vulnerable under the Tasmanian Threatened Species Protection Act 1995.

4. How judged by TSSC in relation to the EPBC Act criteria.

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

Criterion 1 - It has undergone, is suspected to have undergone or is likely to undergo in the immediate future a very severe, severe or substantial reduction in numbers.

The salt marsh habitat of Baudin's Sea-lavender has been fragmented, predominantly through land reclamation for development and changes to land use. For example, one area of habitat, between the remaining Maclaines Creek and Bogan/Alma Creek populations, has been converted to pasture. The number of plants lost is unknown however.

A number of ongoing threats are considered to exist including: physical disturbance from cattle (trampling) and off-road vehicles, light industry effluent; nutrient enrichment from upstream agricultural practices; land fill and urban development. There is also potential for impact on the species' intertidal habitat from offshore activities (e.g. oil and chemical spillages).

While a population reduction is suspected to have occurred, there is insufficient data to quantify this decline. There is also insufficient evidence to indicate that Baudin's Sea-lavender is likely to undergo a reduction in numbers in the immediate future.

There is insufficient quantitative data available against this criterion. Therefore, the species is not eligible for listing under this criterion.

Criterion 2 - Its geographic distribution is precarious for the survival of the species and is very restricted, restricted or limited.

Baudin's Sea-lavender is known from three populations: Vicarys Rivulet; Maclaines Creek; and Bogan/Alma Creeks. It has an estimated extent of occurrence of 0.8km² and an area of occupancy between 1-2 hectares. However, as noted under Criterion 1, there is little quantitative evidence to indicate a continuing decline in numbers or that the total population is subject to extreme fluctuations in numbers or area.

While the species has a restricted geographic distribution, and is known from only three populations, there is insufficient evidence to indicate that this geographic distribution is, in itself, precarious for the survival of the species. While the species is not known to occur in any conservation reserve, there is insufficient evidence to indicate that the existing population of Baudin's Sea-lavender is subject to a continuing decline or extreme fluctuations in population numbers.

The salt marsh habitat of Baudin's Sea-lavender has been fragmented in the past through ongoing land reclamation of marsh habitat for development and pasture use. A number of ongoing threats are considered to exist including: disturbance from cattle (trampling), light industry effluent; nutrient enrichment from upstream agricultural practices; off-road vehicles; land fill and urban development. There is also potential for impact on the species' intertidal habitat from offshore activities (e.g. oil and chemical spillages). However there are no known impacts from these threats at this stage.

The geographic distribution, while restricted, is not considered precarious for the survival of the species as the species is under no immediate threat and appears not to be subject to an ongoing decline. Therefore, the species is not eligible for listing under this criterion.

Criterion 3 - The estimated total number of mature individuals is very low, low, or limited, and: (a) evidence suggests that the number will continue to decline at a very high, high, or substantial rate; or (b) the number is likely to continue to decline and its geographic distribution is precarious for its survival.

The population of Baudin's Sea-lavender is estimated to consist of less than 500 mature individuals. The issue of low numbers is considered under Criterion 4. There is a lack of evidence that the number of mature individuals will continue to decline at a significant rate.

The salt marsh habitat of Baudin's Sea-lavender has been fragmented in the past through ongoing land reclamation of marsh habitat for development and pasture use. A number of ongoing threats are considered to exist including: disturbance from cattle (trampling), light industry effluent; nutrient enrichment from upstream agricultural practices; off-road vehicles; land fill and urban development. There is also potential for impact on the species' intertidal habitat from offshore activities (e.g. oil and chemical spillages). However there are no known impacts from these threats at this stage.

There is insufficient quantitative data available against this criterion. Therefore, the species is not eligible for listing under this criterion.

Criterion 4 - The estimated total number of mature individuals is extremely low, very low or low.

The total population of Baudin's Sea-lavender is low, consisting of fewer than 500 mature plants. This population occurs in three locations and is geographically restricted (extent of occurrence 0.8km², area of occupancy between 1-2 hectares).

The estimated total number of mature individuals is low. Therefore, the species is eligible for listing as vulnerable under this criterion.

Criterion 5 - Probability of extinction in the wild

There is no quantitative data available against this criterion. Therefore, the species is not eligible for listing under this criterion.

5. Conclusion

Baudin's Sea-lavender consists of fewer than 500 mature plants with a restricted geographic distribution. While there is insufficient evidence to indicate that the species' geographic distribution is, in itself, precarious for the survival of the species, the estimated total number of mature individuals is low. The salt marsh habitat of Baudin's Sea-lavender has been fragmented in the past through land reclamation for development and pasture use. A number of threats are considered to be ongoing including: disturbance from cattle (trampling), light industry effluent; nutrient enrichment from upstream agricultural practices; off-road vehicles; land fill and urban development. There is also potential for offshore activities (e.g. oil and chemical spillage) to impact on the species' intertidal habitat.

The species is eligible for listing as vulnerable under criterion 4.

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 vulnerable category:

Conservation Advice

Baudin's Sea-lavender is a perennial herb that occurs only in salt marsh habitat near Triabunna, on the central east coast of Tasmania (South Tasmania NRM region). Baudin's Sea-lavender is currently known from three populations at Vicarys Rivulet, Maclaines Creek, and Bogan/Alma Creeks.

Key threats to the species include: the conversion/land reclamation of its salt marsh habitat to other land uses (e.g. pasture, urban development); physical damage to plants from cattle and off-road vehicles; effluent from light industry entering salt marshes and nutrient enrichment from upstream land use practices and possible pollution from offshore oil and chemical spills.

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

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.

No Recovery Plan is currently in place for Baudin's Sea-lavender.

Priority for the development of recovery plan: Medium.

Publications used to assess the nomination

Schahinger, R. (2004). The taxonomic status of Baudin's Sea-lavender (Limonium baudinii Lincz) with notes on its distribution and conservation status. A report for the Threatened Species Unit, Department of Primary Industries, Water and Environment, Hobart, Tasmania.