Over 110 threatened ecological communities (TECs) are listed under Australia’s Environment Protection and Biodiversity Conservation Act (EPBC Act). TECs are like an ecosystem or series of ecosystems, and listing represents an effective national approach to ‘whole of system’, landscape-scale, connected, and multi-species, conservation. Listed entities become a Matter of National Environmental Significance, which may trigger referral and assessment of proposed developments. A listed TEC also complements and guides other protective measures, such as reserves, management plans, and community restoration projects, and often leverages restoration funding.
Based on a scientific assessment against six regulated ‘Criteria’, listing is overseen by an independent Threatened Species Scientific Committee, with approval by the Commonwealth Environment Minister. Along with a description and guidance on priority protection/recovery actions, the listing assessment is published in a Conservation Advice.
This presentation focuses on the challenges of demonstrating Criterion 3 (C3)—loss or decline of functionally important species, for assessment of the River Murray downstream of the Darling, and associated aquatic and floodplain systems ecological community. This is the first riverine/floodplain system to be listed as threatened under the EPBC Act, and it was approved for listing as Critically Endangered. Criterion 3 considers native species that serve a major ecological role in the processes that sustain the functional integrity and resilience of the ecological community, i.e. keystone-type species.
There were nine taxonomic/ecological categories considered ‘functionally important’ or ‘keystone’ and analysed under C3; this presentation focuses on analysis of the five ‘fish’ categories: Murray Cod (apex predator), Freshwater Catfish (benthic predator, habitat modifier), Congolli (diadromous migrator), small-bodied fish—suite of 6 species (floodplain wetland specialists, food-web dynamics), and Murray Crayfish (detritivore). All were assessed to be Critically Endangered with restoration not likely in the immediate future (except Congolli, Vulnerable); some species were extinct or extirpated. A 'multiple-lines-of-evidence' approach was key.