Biodiversity

Species Profile and Threats Database

For information to assist in referral, environmental assessment and compliance issues, refer to the Listing Advice and/or Conservation Advice and Recovery Plan. The Listing and/or Conservation Advice define the national ecological community and may include Key Diagnostic Characteristics, Condition Thresholds, Priority Research and Conservation Actions and additional considerations.
In addition, for recovery planning, mitigation and conservation information, refer to the Recovery Plan (where available) or the Conservation Advice.


EPBC Act Listing Status Listed as Critically Endangered
Date Effective 07 Jan 2010
Listing and Conservation Advices For ecological communities listed from 2013 onwards, there is no separate listing advice. Instead, the advice from the Threatened Species Scientific Committee regarding the listing status of the ecological community and recommendation regarding a recovery plan are contained within the Conservation Advice.
Commonwealth Listing Advice on Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) (Threatened Species Scientific Committee, 2010a) [Listing Advice].
Commonwealth Conservation Advice on Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) (Threatened Species Scientific Committee, 2010b) [Conservation Advice].
Recovery Plan Decision Recovery Plan not required, the ecological community is restricted to a small area in Western Australia's Yalgorup National Park. The actions required to conserve and promote the recovery of the ecological community are adequately identified in the conservation advice for the community and supported by existing state-based policies to the extent that there is no conservation benefit in having a national recovery plan (18/12/2009).
 
Adopted/Made Recovery Plans
Federal Register of Legislative Instruments Inclusion of ecological communities in the list of threatened ecological communities under section 181 of the EPBC Act 1999 - Thrombolite (microbialite) Community of a Coastal Brakish Lake (Lake Clifton) (18/12/2009) (Commonwealth of Australia, 2009v) [Legislative Instrument].
Indicative Distribution Map(s) Map of Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) (Department of the Environment, Water, Heritage and the Arts (DEWHA), 2010c) [Indicative Map].
Distribution Map Community Distribution Map

This map has been compiled from datasets with a range of scales and quality. Species or ecological community distributions included in this map are only indicative and not meant for local assessment. Planning or investment decisions at a local scale should seek some form of ground-truthing to confirm the existence of the species or ecological community at locations of interest. Such assessments should refer to the text of the Listing Advice, which is the legal entity protected under the EPBC Act.

For the legal definition of the ecological community please refer to the listing advice and other documents under Legal Status and Documents.

Microbialites are discrete organosedimentary structures formed by the activities of specific microbial communities that occur at the bottom (benthic stratum) of certain aqueous ecosystems. Here, cyanobacteria and eukaryotic microalgae photosynthesise and precipitate calcium carbonate (limestone) from the surrounding water, leading to the formation of rock-like structures. Although microbialites have the appearance of rocks, they are in fact living ecosystems similar to coral reefs. Unlike corals, however, the hard carbonate structures of microbialites are not skeletal, but are instead the result of mineralisation in the biochemical environment. Microbialite construction is a passive process, unlike coral skeletal formation, which is an active and controlled precipitation of calcium carbonate by the coral tissues.

Thrombolites are a particular type of microbialite. They are distinguished from other microbialites, such as stromatolites, by the internal structure of their calcareous deposits. Stromatolites are finely layered, whereas thrombolites are not layered, and possess a clotted internal structure with fenestrae. Thrombolites are formed by the interactions of a complex association of photosynthetic prokaryotes, eukaryotic microalgae and true bacteria. They require access to a carbonate-rich water supply and sunlight for their growth and survival. The photosynthetic action of the microbes causes the precipitation of calcium carbonate as aragonite from fresh groundwater seeping up from underground aquifers.

The dominant type of microbe present in the Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) are generally photosynthetic cyanobacteria. Historically, the dominant microbe for thrombolite formation is the cyanobacterium Scytonema sp., which grows in fresh to brackish waters with low nutrient levels. Other cyanobacteria found in the Lake Clifton thrombolites include the genera Oscillatoria, Dichothrix, Chlorococcus, Gloeocapsa, Johannesbaptistia, Spirulina and Gomphosphaeria, as well as numerous species of diatoms.

The Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) is restricted to Lake Clifton, on the Swan Coastal Plain of Western Australia, south of Perth. Lake Clifton is situated within the Yalgorup National Park, and is the northernmost lake in the Peel-Yalgorup Lakes System. The Lake Clifton thrombolite community occurs on a relict foredune plain of Holocene age sands. The main known occurrence of the ecological community is a reef-like formation approximately 15 kilometres long and up to 15 metres wide along the north-eastern shoreline of Lake Clifton. Other smaller clusters of thrombolites are known to occur at the northern end of the Lake Clifton. The thrombolites cover a total area of approximately four square kilometres.


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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). Thrombolite (microbialite) Community of a Coastal Brackish Lake (Lake Clifton) in Community and Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed 2014-07-26T15:38:43EST.