Invasive species and pathogens pressure on the Gondwana Rainforests of Australia
Invasive plants, animals and pathogens pose a threat to Gondwana Rainforests World Heritage values.
A variety of introduced plant and animal species have been recorded and are a problem in parts of the property. This threat is considered high.
Management response to these invasive species includes implementation of threat abatement plans and pest management plans in national parks.
Several introduced pathogens threaten the values of the property including:
- Phytophthora species — a soil-borne water mould which infects the roots of plants
- Batrachochytrium dendrobatidis — a fungus which causes chytridiomycosis in frogs
- Psittacine circoviral (beak and feather) disease infecting parrots
- Austropuccinia psidii — causing the fungal disease, myrtle rust.
Myrtle rust in particular poses a significant long-term threat to the Gondwana Rainforests.
- It has been attributed to the decline of a number of species common to these ecosystems.
- Widespread severe bushfires in 2019–2020 followed by warm wet weather together with large area of regrowth vegetation has created ideal conditions for its spread.
- Myrtle rust could change species composition and native ecosystems, reduce biodiversity, and lead to extinction of some native species.
- Myrtle rust’s spread could provide opportunistic invasion of weed species such as lantana.
- The loss of a broad range of Myrtaceae species could have knock-on impacts for pollinators and fauna dependant on these species for seasonal food supply.
A better understanding of impact and variability in susceptibility within different affected Myrtaceae species is required before a management plan can be developed. Selecting for resistance and re-introduction of species as part of regeneration programs is a viable long-term management approach for some species.
Unprecedent dieback of 800-year-old Bunya Pines in the Bunya Mountains (part of the Gondwana Rainforests World Heritage Tentative List) is being investigated.
- Phytophthora is thought to be the cause.
- Loss of these tree species will result in broader ecological impacts within this rainforest ecosystem.
Management actions to address the threat of pathogens are, in part, dealt with in the relevant national park management plans and statements. Given the nature of the property as a serial listing, it is difficult to impose biosecurity controls and manage the spread of pathogens without coordinated, landscape-scale measures.
- Statement of Outstanding Universal Value
- World Heritage outlook
- The Gondwana Rainforests of Australia World Heritage Area (extension to existing property)