Indicative distribution
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas.
(
click here to see geographic restrictions).
The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Eriocaulon carsonii
Profile last updated:
01 Nov 2022
Description
Small tufted herb with flowering stems 3-8 cm high. Leaves lance-shaped in a basal tuft, 1.5-6 cm long and 3-10 mm wide, striped. Flowerhead spherical, 3-4 mm diameter, a mixture of male and female flowers, all surrounded by stiff and transparent bracts. All flowers have 2 whorls of segments, the male with inner whorl fused, the female with both whorls free. Fruit a membranous, swollen, 3-celled capsule, seeds solitary in each cell.
Distribution
Very rare, occurring west from the Tilpa district in far north-western NSW, into the Lake Eyre region of SA and Qld. Only two sites were previously known in NSW, the type locality of Wee Wata Springs where the species was first collected in 1888, and Peery Lake 40km east of White Cliffs and some 100 km from the type locality. Wee Wata Springs has been examined several times in the last few decades but the mound spring has been destroyed by trampling stock. Another site recorded near Tilpa in 1888 also lacks current specimens. Extant on up to eight mounds on the western side of Peery Lake but varies from year to year.
Habitat and ecology
- Grows in running water and forms dense mats in wet soil around shallow springs. The species is an endemic of active or flowing artesian mound springs on the margins of the Great Artesian Basin.
- Mound springs are natural outlets of the Basin, associated with fractures and fault lines, often having mounds of various sizes. Accumulated evaporite and mud deposits form mounds 1 to 10 metres high and 2 to 100+ metres in diameter. The faults provide direct access for the artesian water to reach the surface. These landforms are probably one of the rarest habitats in Australia.
- Originally restricted to a single mound at Peery Lake in NSW, in an area of many mounds. More recently the plant has spread to adjacent mounds, then contracted again, suggesting that stochastic events are strongly influencing population stability.
- The population structure of Eriocaulon carsonii changed after fencing at Elizabeth Springs in Qld, with large numbers of small immature plants replaced by a smaller number of larger plants.
- Observations of density of kangaroo scats at Peery Lake suggest that kangaroos heavily graze the mounds. Kangaroo grazing apparently limits the growth of sedges on the mounds, reducing competition, thus benefiting Eriocaulon carsonii.
- The species is often recorded growing in dense mats of numerous individuals.
Regional distribution and habitat
Click on a region below to view detailed distribution, habitat and vegetation information.
Threats
- Limited habitat availability. This species is endemic to the Great Artesian Basin spring wetlands, found in extremely rare and specialised mounds within the springs, making it highly vulnerable to catastrophic events which may alter or destroy this habitat.
- This species is endemic to the Great Artesian Basin spring wetlands, found in extremely rare and specialised mounds within the springs, making it highly vulnerable to catastrophic events.
- Lack of knowledge of the species distribution, ecology and habitat requirements. The patterns of plant and animal distributions within individual spring wetlands and the effects of disturbance and changes in water flow are poorly understood.
- Damage caused by feral pigs through rooting and wallowing.
- Invasion and competition by invasive transformer weed species.
- Habitat clearing and modification (through artesian drawdown and continuous grazing; most mound springs are no longer flowing and lack the necessary surface water to support the species).
- Grazing and trampling by stock.
- Competition (when grazing is completely excluded, the species cannot compete with the many sedges and grasses which thrive on the artesian springs).
- Browsing and damage from feral goats
Recovery strategies
A targeted strategy for managing this species has been developed under the Saving Our Species program; click
here for details. For more information on the Saving Our Species program click
here
Activities to assist this species
- Long-term control of feral pigs at Peery Lake (through fencing, the structure of which should also allow kangaroos to graze the springs, to prevent an explosion of sedges may severely reduce numbers of Eriocaulon carsonii).
- No further degradation or loss of potential habitat.
- Protect existing populations from stock with the construction of appropriate fencing.
- Control of competitive sedge and grass species such as Phragmites.
- No further loss of extant populations.
- Baseline surveys required to confirm known and locate new populations.
Information sources
- Ayers, D., Nash, S. and Baggett, K. (1996) Threatened Species of Western New South Wales. (NSW National Parks and Wildlife Service, Sydney)
- Briggs, J.D. and Leigh, J.H. (1996) Rare or Threatened Australian Plants. Revised Edition. (CSIRO Publishing, Melbourne)
- Conn, B.J. (1993) Eriocaulon. In Harden, G.J. (ed.) Flora of New South Wales. Volume 4. New South Wales University Press: Sydney.
- Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992) Plants of Western New South Wales. (Inkata Press, Sydney)
- Evans, O.D. (1966) Flora of New South Wales. Eriocaulaceae. Contributions from the New South Wales National Herbarium. Flora Series 27-28.
- Fatchen, T.J. and Fatchen, D.H. (1993) Dynamics of Vegetation on Mound Springs in the Hermit Hill Region, Northern South Australia (TJ Fatchen & Associates: Adelaide).
- Jacobs, S.W.L. (1999) Terrestrial wetlands and waterplants. Flora of Australia 1: 403-416, p. 410.
- Jessop, J.P. (1981) Flora of Central Australia. (Australian Systematic Botany Society, Sydney)
- Jessop, J.P. and Toelken, H.R. (eds.) (1986) Flora of South Australia. Part lll. (South Australian Government Printing Division, Adelaide)
- Mackay, D.A., Whalan, M.A. and Niejalke, D.P. (1998) Thoughts on worts found on mounds. In Niejalke, D.P. (ed.) Proceedings to the 2nd Mound Springs Researchers Forum and Spring Management Workshop (WMC Limited: Adelaide).
- NSW National Parks and Wildlife Service (2003) Eriocaulon carsonii (a shrub) Recovery Plan. NSW NPWS, Hurstville NSW.
- Pressey, R.L., Cohn, J.S. and Porter, J.L. (1990) Vascular plants with restricted distributions in the Western Division of New South Wales. Proceedings of the Linnean Society of New South Wales 112: 213-227
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