Thinking threatened species for National Biodiversity Month

September is National Biodiversity Month in Australia, promoting the importance of connecting with nature and caring for the natural environment and the diversity of life it contains.

Conserving natural places, ecosystems and wildlife through planning and on-ground action for threatened species and ecological communities is a key focus for Landscapes Hills and Fleurieu.

The Hills and Fleurieu region is rich in biodiversity and the Mount Lofty Ranges is part of one of the 15 biodiversity hotspots in Australia. A biodiversity hotspot is an area rich in animal and plant species, particularly those which are endemic or restricted to a specific region or site. Half of the state’s native plant species and three quarters of its native bird species live in our region. In the Hills and Fleurieu, which includes the southern Mount Lofty Ranges, regional conservation assessments have identified 126 fauna species and 445 flora species that are considered threatened. Just as startling, it is estimated that 37 fauna species and 38 flora species are regionally extinct.

What defines a threatened species?

‘Threatened species’ are those species or subspecies which are threatened with extinction.

Some are more threatened, or at greater risk of extinction than others. Special criteria including population size, geographic range and rate of decline are used to assess each species’ conservation status and assign them to a category that reflects their risk of extinction.

How do species become threatened?

The threats that can increase extinction risk are many and varied. Primary threats include the loss, fragmentation and degradation of habitat; disease; altered fire regimes; and competition or direct predation from invasive species. Other threats include climate change; changes to water flows; unsustainable use of natural resources and many others.

You may have seen terms like Critically Endangered (CR), Endangered (EN) or Vulnerable (VU). The species listed under these categories are all considered ‘threatened’ under Australian and State Government legislation. These species are considered to be facing an extremely high to high risk of extinction in the wild.

But it goes a little deeper than that…

How is a conservation status assigned in Australia?

An internationally recognised assessment method was developed by the International Union for Conservation of Nature (IUCN) to classify species into nine categories - Extinct (EX), Extinct in the Wild (EW), Critically Endangered (CR), Endangered (EN), Vulnerable (VU), Near Threatened (NT), Least Concern (LC), Data Deficient (DD) and Not Evaluated (NE).

Australia has formally adopted the IUCN thresholds for Critically Endangered, Endangered and Vulnerable for the assessment and listing of threatened species and threatened ecological communities.

National, state and regional conservation status assessments are also undertaken in accordance with relevant legislative frameworks.

At a National level, threatened fauna and flora may be listed under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) in any one of six categories: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable and Conservation Dependent.

In South Australia, threatened species are listed under the threatened species schedules of the National Parks and Wildlife Act 1972 (NPW Act). The current categories and order of the schedules under the NPW Act are Endangered (including critically endangered and extinct), Vulnerable and Rare. The Rare category is not recognised in the IUCN structure however it is consistent with current IUCN definitions for 'Near threatened'.

Freshwater and marine fish, some marine invertebrates and crustaceans are protected under the Fisheries Management Act 2007 in South Australia. Some of these species are known to be threatened but do not currently have a legal conservation status listed under the NPW Act.

Some examples of threatened species and subspecies that occur in the Hills and Fleurieu region under either EPBC Act, NPW Act or regional assessments include:

• Mount Lofty Ranges chestnut-rumped heathwren (EN)

• Eastern hooded plover (VU)

• Mount Compass oak-bush (EN)

• Western beautiful firetail (EN)

• Fleurieu leek orchid (CR)

• Yarra pygmy perch (VU)

• Varied sittella (VU)

• Cunningham’s skink (EN)

• Western pygmy-possum (CR)

• Black-chinned honeyeater (VU)

• Yellow-bellied water skink (VU)

• White beauty spider-orchid (EN)

Conserving our Biodiversity

We are fortunate to live and work in a region with productive soils, good rainfall and ‘usually’ hospitable temperatures. Our region’s biodiversity helps support our wellbeing, health, and economy, and in turn, it needs us to help conserve and manage it.

If you would like to learn more about what we’ve been doing to conserve our region’s biodiversity, visit this page to see the successes of our recently completed 5-year, Australian Government funded, Back from the Brink Project. This project aimed to reduce the extinction risk of 37 nationally threatened flora and fauna species and two nationally threatened ecological communities within the Adelaide and Mount Lofty Ranges and Fleurieu Peninsula.