Biodiversity

Our Catchment is nestled within the South West WA International Biodiversity Hotspot, recognised for its high number of rare and endemic plants and animals.

Biodiversity Hotspot at a glance:

  • 7000 plant species
  • 44 reptile species
  • 16 marsupials
  • 10 mammals
  • 7 introduced mammals
  • 8 threatened species

Less than 37% of the pre-European vegetation remains in the Catchment, including 24 Declared Rare flora species and 13 threatened ecological communities.

Our diverse landscapes include the iconic marri, jarrah and blackbutt forests in the upper Catchment, which change to flooded gum and paperbarks around our waterways, and to peppermint and tuart woodlands along the coastline. These habitats support critically endangered species like the Western Ringtail Possum.

Conservation

Managing remnant vegetation is critical to the long-term survival of threatened flora, fauna and ecological communities, and to building resilience to climate change. Reducing habitat loss and fragmentation, and minimising the impacts of grazing, feral and domestic animals, tree decline (fact sheet), weed invasion, and changing fire regimes, will help protect our native wildlife. Fauna that has been afforded special protection status include the Western Ringtail Possum, Chuditch, Quokka, Australian Bittern, Carter’s Freshwater mussel, Dunsborough Burrowing Crayfish, Baudin’s Black Cockatoo, Carnaby’s Black Cockatoo, and the Forest Red-tailed Black Cockatoo. There are also a range of threatened fish species, migratory birds and whales.

Recovery Plans are in place for the Chuditch, Carnaby’s, Baudin’s and Forest Red-tailed Black Cockatoos, Australian Bittern, Dunsborough Burrowing crayfish and for Western Ringtail Possum, which is listed as critically endangered through the Environment Protection and Biodiversity Conservation Act.

Western Ringtail Possum

The Geographe Bay Catchment has one of the most significant remaining populations of Western Ringtail Possum (WRP) in the world.

The Western Ringtail Possum has disappeared from 90% of its original range due to:

  • Land clearing for agriculture and urban development
  • Logging and burning of South West forests
  • Predation by foxes and feral cats
  • Domestic cat and dog attacks
  • Traffic accidents
  • Rat and snail bait poisoning
  • Relocation to unsuitable habitat
  • Diseases such as toxoplasmosis, which is carried by cats

Peppermint trees (Agonis flexuosa), or peppies as they are known locally, make up to 95% of the diet of the Western Ringtail Possum in the wild. The clearing of this habitat for urban development is a significant threat to one of the last stronghold populations of the species.

The Western Ringtail Possum is listed as specially protected fauna that is rare or likely to become extinct under the WA Wildlife Conservation Act 1950 (WC Act), and is ranked as Critically Endangered under Department of Parks and Wildlife policy using IUCN criteria. It is listed nationally as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and as threatened (Vulnerable category) in the IUCN Red List (IUCN 2012).

Ongoing community concerns about the Western Ringtail Possum in the Busselton area led to the initiation of the Peppies for Possums program and associated campaigns. We work to protect the habitat of the Western Ringtail Possum through population surveys, weed control, site preparation and planting of Peppermint trees in priority areas, and awareness raising in schools and the wider community.