Biodiversity

Species Profile and Threats Database


For information to assist proponents in referral, environmental assessments and compliance issues, refer to the Policy Statements and Guidelines (where available), the Conservation Advice (where available) or the Listing Advice (where available).
 
In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.

EPBC Act Listing Status Listed as Critically Endangered
Listing and Conservation Advices Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
 
Commonwealth Conservation Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009ch) [Conservation Advice].
 
Recovery Plan Decision Recovery Plan not required, "a Tasmanian Government regional multi-species recovery plan incorporates this species and it occurs within an area currently managed as a wildlife sanctuary. Combined with the approved conservation advice for this species, there is sufficient direction to implement priority actions and manage key threats (20/10/2009)".
 
Adopted/Made Recovery Plans
Other EPBC Act Plans Flora Recovery Plan: Tasmanian Threatened Orchids 2006-2010 (Threatened Species Section (TSS), 2006a) [Recovery Plan].
 
Policy Statements and Guidelines Draft survey guidelines for Australia's threatened orchids (Department of the Environment, 2013b) [Admin Guideline].
 
Federal Register of
    Legislative Instruments
Inclusion of species in the list of threatened species under Section 178 of the Environment Protection and Biodiversity Conservation Act 1999 (81) (20/10/2009) (Commonwealth of Australia, 2009g) [Legislative Instrument].
 
State Government
    Documents and Websites
TAS:Prasophyllum limnetes (Marsh Leek-orchid): Species Management Profile for Tasmania's Threatened Species Link (Threatened Species Section (TSS), 2014av) [State Action Plan].
TAS:Prasophyllum limnetes - Profile (Threatened Species Section (TSS), n.d.) [Information Sheet].
TAS:Flowering Times of Tasmanian Orchids: A Practical Guide for Field Botanists (Wapstra, M., N. Roberts, H. Wapstra & A. Wapstra, 2008) [Information Sheet].
State Listing Status
TAS: Listed as Endangered (Threatened Species Protection Act 1995 (Tasmania): September 2012 list)
Scientific name Prasophyllum limnetes [82678]
Family Orchidaceae:Orchidales:Liliopsida:Magnoliophyta:Plantae
Species author D.L.Jones
Infraspecies author  
Reference Jones, D.L. & Rouse, D.T. (2006) Australian Orchid Research 5: 151-152
Distribution map Species Distribution Map

This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.

Illustrations Google Images

Scientific name: Prasophyllum limnetes

Common name: Marsh Leek-orchid

The species is conventionally accepted as Prasophyllum limnetes (Marsh Leek-orchid) (Jones 2006). It was previously considered to belong to Prasophyllum pyriforme (Graceful Leek-orchid) which is no longer recognised as occurring in Tasmania (Jones 2006).

The Marsh Leek-orchid is a small, fleshy, terrestrial orchid with a solitary erect leaf that is 20–35 cm long and 2–4 mm wide. Flowers are densely crowded along a flower spike 8–12 cm long. The flowers are greenish in colour with brown, pink or mauve tones in the labellum. The labellum is 6–7 mm long, with broadly flared margins at the base, sharply recurved and constricted near the middle, and with a tail-like tip (Jones 2006; Jones & Rouse 2006).

The Marsh Leek-orchid is endemic to Tasmania. It has been recorded only at the Rubicon Sanctuary, near Port Sorell, in the central north of Tasmania, approximately 20 km west of Devonport. The site is approximately 10 m above sea level. It is located within the North West Natural Resource Management Region (TSSC 2009cg).

The species' distribution is very restricted, as the known population is small and exists within a patch of remnant vegetation surrounded by improved pasture and housing estates (TSSC 2009cg). The species' area of occupancy is estimated to be a few square metres (P. Tonelli 2007, pers. comm., cited in TSSC 2009cg).

The Marsh Leek-orchid is now known from only one population in the Rubicon Sanctuary. Some decline in this population may have occurred, as 12 individuals were recorded in 1999 (Tas. DPIWE 2000) and five individuals were recorded in 2007 (P. Collier & R. Garnett 2007, pers. comm., cited in TSSC 2009cg). However, studies on the related Gaping Leek-orchid (Prasophyllum correctum) indicate that plants may not appear every year, and may survive below ground in a dormant state for up to five years (Coates et al. 1999). Therefore, the fewer number of individuals counted in 2007 may be a result of dormancy rather than decline.

There are insufficient data to determine historic or current population trends for the Marsh Leek-orchid. However, it is likely that the species was more widespread prior to the vegetation clearance and fragmentation that occurred since European settlement of the area (Tas. DPIWE 2000).

The Marsh Leek-orchid grows in an ecotone between low-lying marshy heath/sedgeland dominated by rushes and sedges with scattered patches of Spiny-headed Mat-rush (Lomandra longifolia) and Kangaroo Grass (Themeda triandra), and coastal Eucalyptus amygdalina woodland with a heathy/grassy understorey (TSSC 2009cg).

The Marsh Leek-orchid flowers in late November–December. The species may require disturbance to stimulate emergence and flowering and is currently only found in areas that are slashed or burned regularly. Studies on the related Gaping Leek-orchid indicate that plants may not appear every year, and may survive below ground in a dormant state for up to five years (Coates et al. 1999). Orchids, including the Marsh Leek-orchid, have a complex and poorly understood interrelationship with species-specific mycorrhizal fungi and insect pollinators (Jones et al. 1999). Native bees, wasps and beetles are known to be effective pollinators for other Prasophyllum species, while some species can also be self-pollinating (Jones et al. 1999). Leek-orchids are not known to reproduce vegetatively and recruitment is from seed. Evidence suggests that the species does not self-pollinate without intervention (TSSC 2009cg).

Unlike other orchids at the site, no seed was set by the five Marsh Leek-orchid individuals that flowered in 2007. This may indicate that the population is now too small to attract pollinators or that the small population size has led to incompatibility problems through insufficient genetic variation (TSS n.d.).

The main threats to the Marsh Leek-orchid are inappropriate disturbance, loss of pollinators and mycorrhizal fungi, and climate change. Historically, decline in the species is likely to have been caused by vegetation clearance and fragmentation; however, the species is now restricted to a reserve where it is protected from these threats.

Inappropriate disturbance
Long periods without disturbance may lead to prolonged dormancy with increased risk of mortality through depletion of stores of starch in underground tubers. Conversely, burning too frequently (e.g. annually) may adversely affect mycorrhizal fungi communities, rendering the site unsuitable for fungal-dependent orchid species (Brundrett 2007), including the Marsh Leek-orchid. Slashing at the wrong time of year can damage plants and prevent seed from being produced (TSSC 2009cg).

Loss of pollinators and mycorrhizal fungi
Potential threats include the loss of pollinators and mycorrhizal fungi. The Marsh Leek-orchid has a very small population, which may lead to inbreeding problems and increases the species' susceptibility to stochastic events. The small size of the population may also be insufficient to sustain pollinators and mycorrhizal fungi (TSSC 2009cg).

Climate change
Climate change is a further potential threat as changes in the rainfall pattern may lead to the habitat becoming unsuitable for the species and associated pollinators and mycorrhizal fungi. As a near-coastal species, the Marsh Leek-orchid is also particularly susceptible to changes in sea level and extreme tidal variations, which may result from climate change (TSSC 2009cg).

Minister's reasons for recovery plan decision
A Tasmanian Government regional multi-species recovery plan incorporates this species and it occurs within an area currently managed as a wildlife sanctuary. Combined with the approved conservation advice for this species, there is sufficient direction to implement priority actions and manage key threats. A national recovery plan is not considered to be necessary at this time.

The Commonwealth Conservation Advice on Prasophyllum limnetes (Marsh Leek-orchid) (TSSC 2009cg) outlines the following research priorities:

  • Design and implement a monitoring program with more frequent surveys or, if appropriate, support and enhance existing programs.
  • More precisely assess population size, distribution, ecological requirements and the relative impacts of threatening processes.
  • Develop a better understanding of life history, disturbance ecology and identification of pollinators; and the implications of these for management.
  • Undertake survey work in suitable habitat and potential habitat preferably during the late November–December flowering period, to locate any additional populations/ occurrences/remnants.
  • Undertake seed germination and/or vegetative propagation trials to determine the requirements for successful establishment, including mycorrhizal association trials.
  • Identify appropriate intensity and interval of fire to promote seed germination and vegetation regeneration.
  • Develop and implement a suitable fire management strategy for the Marsh Leek-orchid.

In addition, the Commonwealth Conservation Advice on Prasophyllum limnetes (Marsh Leek-orchid) (TSSC 2009cg) outlines the following priority actions:

  • Monitor known populations to identify key threats.
  • Monitor the progress of recovery, including the effectiveness of management actions and the need to adapt them if necessary.
  • Manage any disruptions to water flows.
  • Manage any other known, potential or emerging threats including inappropriate disturbance, loss of pollinators and effects of climate change.
  • Suitably control and manage access on private land.
  • Undertake survey work in suitable habitat and potential habitat to locate any additional populations/occurrences/remnants.
  • Minimise adverse impacts from land use at known sites.
  • If additional unprotected populations are found, protect populations of the listed species through the development of conservation agreements and/or covenants.
  • Raise awareness of the Marsh Leek-orchid within the local community.
  • Frequently engage with landholders and land managers responsible for the land on which populations occur and encourage these key stakeholders to contribute to the implementation of conservation management actions.
  • Undertake appropriate seed and mycorrhizal fungi collection and storage.
  • Investigate options for linking, enhancing or establishing additional populations.
  • Implement national translocation protocols (Vallee et al. 2004) if establishing additional populations is considered necessary and feasible.

The Department of Primary Industries and Water has developed the Flora Recovery Plan: Threatened Tasmanian Orchids 2006–2010 (TSS 2006a). In this plan, the population (under the name of Prasophyllum pyriforme) is a priority population for recovery actions to be implemented. It recommends appropriate disturbance, monitoring, survey, storage of seed and fungi and increased awareness.

The Commonwealth Conservation Advice on Prasophyllum limnetes (Marsh Leek-orchid) (TSSC 2009ch) provides a brief biological overview and management recommendations. In addition, the Flora Recovery Plan: Threatened Tasmanian Orchids 2006–10 (TSS 2006a) is available.

The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.

Threat Class Threatening Species References
Climate Change and Severe Weather:Climate Change and Severe Weather:Reduced rainfall caused by climate change Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
Climate Change and Severe Weather:Habitat Shifting and Alteration:Habitat loss, modification and/or degradation Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
Human Intrusions and Disturbance:Human Intrusions and Disturbance:Human induced disturbance due to unspecified activities Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
Natural System Modifications:Fire and Fire Suppression:Inappropriate and/or changed fire regimes (frequency, timing, intensity) Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
Species Stresses:Indirect Species Effects:Low numbers of individuals Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].
Species Stresses:Indirect Species Effects:Poor recruitment (regeneration) and declining population numbers Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid) (Threatened Species Scientific Committee (TSSC), 2009cg) [Listing Advice].

Brundrett, M.C. (2007). Scientific approaches to Australian temperate terrestrial orchid conservation. Australian Journal of Botany. 55:293-307.

Coates, E., I. Lunt & H. Wapstra (1999). Draft Recovery Plan 2000-2003 Prasophyllum correctum (Gaping leek-orchid). Unpublished report to Environment Australia. Bundoora, Victoria: La Trobe University.

Jones, D., H. Wapstra, P. Tonelli & S. Harris (1999). The Orchids of Tasmania. Carlton South, Victoria: Melbourne University Press.

Jones, D.L. (2006). A complete guide to Native Orchids of Australia, including the island Territories. Sydney, NSW: New Holland Publishers (Australia) Pty Ltd.

Jones, D.L. & D.T. Rouse (2006). Fourteen new species of Prasophyllum from eastern Australia. Australian Orchid Research. 5:143-156.

Tasmania Department of Primary Industries, Water and the Environment (Tas. DPIWE) (2000). Listing statement: Graceful leek orchid Prasophyllum pyriforme. Hobart, Tasmania: DPIWE.

Threatened Species Scientific Committee (TSSC) (2009cg). Commonwealth Listing Advice on Prasophyllum limnetes (Marsh Leek-orchid). [Online]. Department of the Environment, Water, Heritage and the Arts. Canberra, ACT: Department of the Environment, Water, Heritage and the Arts. Available from: http://www.environment.gov.au/biodiversity/threatened/species/pubs/82678-listing-advice.pdf.

Threatened Species Scientific Committee (TSSC) (2009ch). Commonwealth Conservation Advice on Prasophyllum limnetes (Marsh Leek-orchid). [Online]. Department of the Environment, Water, Heritage and the Arts. Canberra, ACT: Department of the Environment, Water, Heritage and the Arts. Available from: http://www.environment.gov.au/biodiversity/threatened/species/pubs/82678-conservation-advice.pdf.

Threatened Species Section (TSS) (2006a). Flora Recovery Plan: Tasmanian Threatened Orchids 2006-2010. [Online]. Hobart, Tasmania: DPIWE. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/tasmanian-orchid.html.

Threatened Species Section (TSS) (n.d.). Prasophyllum limnetes - Profile. [Online]. Hobart, Tasmania: Tas DPIWE. Available from: http://www.dpipwe.tas.gov.au/inter.nsf/Attachments/LJEM-7QE64B/$FILE/Prasophyllum%20limnetes.pdf. [Accessed: 02-Dec-2009].

Vallee, L., T. Hogbin, L. Monks, B. Makinson, M. Matthes & M. Rossetto (2004). Guidelines for the translocation of threatened plants in Australia - Second Edition. Canberra, ACT: Australian Network for Plant Conservation.

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This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.

Citation: Department of the Environment (2014). Prasophyllum limnetes in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Tue, 23 Sep 2014 18:32:29 +1000.