Forêts humides Gondwana de l’Australie

Incompatible land-use on adjoining properties, escaped fires, groundwater extraction, uncontrolled domestic animals, garden weeds, feral animals and pressure for residential and tourist development may pose a threat in some locations. Off-site activities such as clearing and erosion within upstream catchments present a threat for the attributes of the Outstanding Universal Value in some sections of the World Heritage site (IUCN Consultation, 2017). The approval and construction of ecotourism infrastructure in some sections of the site have been subject to a thorough Environmental Impact Assessment process and approved by the federal and state government authorities (Queensland Department of the Environment, Tourism, Science and Innovation; Commonwealth Department of Climate Change, Energy, the Environment and Water).

These Gondwana remnants are effectively islands of rainforest habitat in a sea of various land uses and threats with long and complex boundaries with these land uses and high ratios of 'exposed edges' when compared to internally reserved areas in many cases. This means that dispersed activities such as beekeeping, broad acre cropping, weed treatment, changes in run-off patterns, or broader ground water extraction may sometimes penetrate into the reserve and are difficult to manage.

Tourism development, increasing visitor numbers and visitor infrastructure is identified as a threat in some park management plans. There are high levels of visitation in several visitor precincts in a number of the reserves (IUCN Consultation, 2017). Visitation is managed to minimise impact while supporting the visitor experience and appreciation of values. Where management of human visitation is identified as an action required to protect a threatened species managed under the NSW Government’s Saving our Species program, responses of the target species to threat management are monitored. The Queensland’s State of the Environment Report (SoE, 2017) indicated that increasing visitor numbers, and associated supporting infrastructure, present a minor and localised threat, addressed within the relevant national park management plans and statements and considered the threat are low (SoE, 2017). Major flooding events caused landslides, tree falls, flood debris, and major repeat damage to facilities and infrastructure including roads, fire trails, bridges, causeways and walking tracks across the Gondwana Rainforests impacting visitation (State Party of Australia, 2022).

Several introduced pathogens threaten the values of the World Heritage site including Phytophthora cinnamomi (a soil-borne water mould which infects the roots of native plants); Batrachochytrium dendrobatidis, a fungus which causes chytridiomycosis in frogs (amphibian chytrid disease); psittacine circoviral (beak and feather) disease infecting parrots, and myrtle rust (a disease of native Myrtaceae plants caused by the exotic fungus Austropuccinia psidii (initially identified as Uredo rangelii). The rapid spread and extraordinary impact of this pathogen poses a significant threat to the Gondwana Rainforests and has been attributed to the decline of Rhodamnia rubescens and Rhodomyrtus psidioides, which are now listed in both NSW and QLD as Critically Endangered (Threatened Species Scientific Committee, 2019; QLD Nature Conservation Act 1992). R. psidioides is one of the ten most seriously affected species in southeast Queensland with numerous reports of localized extinction in that area (Makinson, 2018). Lenwebbia sp. Main Range was also listed a critically endangered in NSW in October 2020, with Myrtle rust a key factor in the deteriorating status of this species (Threatened Species Scientific Committee, 2020). Extensive surveys assessing the impact of Myrtle rust were conducted following the 2019–2020 wildfires, funded by the Threatened Species Hub of the Australian Government National Environmental Science Program. Myrtle rust symptoms and damage were found in all survey sites in fire-affected areas of the Gondwana Rainforests. Myrtle rust prefers young leaves and the mass of new epicormic regrowth and young seedlings after fire provided the ideal conditions for the development and spread of the pathogen. Significant impacts were identified on Rhodamnia rubescens (scrub turpentine). Ongoing work will include monitoring of key sites, collection of material for ex-situ propagation, and augmentation of key populations with ex-situ material when required. The range of restricted and endangered Uromyrtus australis (peach myrtle), was also identified as being impacted. Work to address these impacts will include actions to exclude fire from relevant sites, monitoring myrtle rust and other threats, and further assessment of germination to identify issues affecting poor recruitment. In Queensland, the threat of myrtle rust is also being included in post-fire updates to inform national park planning processes. In addition, in certain national parks, hygiene protocols are being strengthened with improved vehicle washdown and visitor footbath facilities as part of the Bushfire Recovery Program.

Bushfires in the spring and summer of 2019–20 impacted approximately 196,000 hectares, or 53%, of the Gondwana Rainforests, including part of the ancient rainforests communities that are not adapted to regular fires. Ecological impacts from these fires were varied across the property (State Party of Australia, 2024). In several areas fires have burnt into rainforest that had previously never recorded a fire since management records commenced in the 1950s and 1960s and were generally considered resistant to fire. The fires were preceded by a prolonged drought and were coincident with a period of above average temperatures and below average rainfall (Australian Bureau of Meteorology Special Climate Statement 71, September 2019). Consequently, the rainforest endured the additive effects of high temperatures, lower precipitation, fires and shortly after, floods that eroded soils. Fire weather is projected to worsen, bushfires are likely to be of higher intensity, and bushfire seasons are likely to start earlier and last longer. This is decreasing the time in between fire seasons and may reduce opportunities for planned burning and fire-fighting resource sharing. A secondary impact of fire is exposed ground soil surface that as easily eroded by subsequent rainfall and major flooding as occurred 2021-22 (State Party of Australia, 2022).

A multitude of plant and animal species as attributes of World Heritage values are affected by fires and associated threats and the monitoring of fire impacts is ongoing.

Immediately following the 2019-20 bushfires significant funding was provided for bushfire recovery. There have not been any further extensive fires in the World Heritage property since 2019-20. Bushfire recovery continues to be part of the ongoing management at the property (State Party of Australia, 2024). Australia recognises the impact of climate change on the frequency and intensity of bushfires, and has committed to national and international climate action. In NSW, ecological consultants were contracted to undertake an assessment of the most heavily impacted reserves within the Gondwana Rainforests including Barrington Tops, Gibraltar Range, Washpool, New England, Oxley Wild Rivers, Werrikimbe, and Willi Willi national parks and the Castles Nature Reserve. They used a range of remote, aerial and field survey techniques to complete the rapid assessment with recommendations made for priority areas of impact and further work, such as identifying ecological communities to target recovery efforts. NSW NPWS staff assessed impacts in the remaining reserves (State Party of Australia, 2022) and a range of long-term monitoring studies were initiated. In Queensland, the then Department of Environment and Science undertook post-fire assessments on the three Gondwana Rainforests WH properties impacted by fire – Lamington NP, Mt Barney NP and Main Range NP (Hines et.al. 2020, 2021, 2022). Assessments included: fire extent and severity mapping using pre- and post-fire satellite imagery, with subsequent ground truthing; evaluation of ecological impact on ecosystems and significant species and; key management recommendations. Targeted threatened species assessment and threat management were also undertaken (Churchill et al. 2023).

Efforts to increase collaboration with the First Nations peoples of the Gondwana Rainforests, ongoing monitoring, pest plant and animal control, and enhanced fire management are being undertaken and will assist with recovery. Both NSW and Queensland are investing in new methods to monitor the health of the Gondwana Rainforests (together with other protected areas) and to evaluate management effectiveness and inform future actions. The Australian, NSW and Queensland governments continue to support and implement bushfire recovery actions. Management is shifting from immediate to longer-term recovery, and lessons identified in the 2019-20 bushfire season are being used to inform bushfire preparedness and ongoing management. To this end, land managers are working to enhance the application of techniques that reduce the risk and impacts of severe bushfire in the World Heritage property such as prescribed burns, pest management, monitoring programs, fire response planning, improved access and water infrastructure.

Removing ecosystem transforming weeds has been a priority for on-ground works across the fire impacted sections of the property (State Party of Australia, 2022). A variety of invasive plant species have been recorded including ox-eye daisy (Leucanthemum vulgare), and bitou bush (Chrysanthemoides monilifera subsp.rotundata) which affect coastal areas; mistflower (Ageratina riparia), crofton weed (Ageratina adenophora), lantana (Lantana camara), blackberry (Rubus fructicosus), camphor laurel (Cinnamomum camphora), broad-leaved privet (Ligustrum lucidum) and small-leaved privet (L. sinense), Kahili ginger (Hedychium gardnerianum), Madeira vine (Andredera cordifolia), moth vine (Araujia sericifera), cat's claw creeper (Macfadyena unguis-cati) and others. Scotch broom (Cytisus scoparius) is a particular problem in the southernmost part of the World Heritage site. At Barrington Tops, Scotch broom forms dense thickets that exclude native species, leading to its complete dominance of the understorey and eventually the canopy. These thickets also impede access, alter fire regimes and dominate the landscape. The weed is spread by animals and in water, such as creeks (OEH, 2014). Management response is guided by invasive species management plans in national parks. Treatment may include use of mechanical, chemical or biological controls that may each bring their own risks. Weeds able to establish in full shade (i.e. exploit intact rainforest) and affect the canopy are possibly the group of greatest threat to the site, while weeds in shade intolerant groups are most likely to be a threat to riparian edges and fragmented remnants (DECCW, 2010). High biomass weeds including invasive grasses and lantana can increase fire risk, particularly along forest edges. Areas of fire affected rainforest where the rainforest has had large scale impacts such as canopy loss are now carrying a vastly increased surface layer weed load of relatively common weed species. The long- term effect on the recovery of the rainforest by these pioneer weed species is unknown (IUCN Consultation, 2020c).

The Gondwana Rainforests of Australia is a serial World Heritage site comprised of eight separate groups of reserves, containing more than 40 component parts, often separated by some distance and spread across a wide latitudinal band. The Gondwana Rainforest reserves contain the major remaining areas of rainforest in north-east New South Wales and south-east Queensland and are disjunct in places due mainly to the naturally fragmented distribution of rainforest in this part of Australia. Some of the reserves are very small, but have some connectivity to neighbouring protected areas, often with the same or very similar values. The area to boundary ratio of fragmented reserves increases exposure to threats such as fire, weed and pathogen invasion, changes in the microclimate of otherwise intact rainforest, and potentially has negative impacts on natural biological processes (including altitudinal and latitudinal migration in response to climate change) (IUCN Consultation, 2017). On balance the Outstanding Universal Value of the site is secured through the large reserves, which represent the majority of the World Heritage site (Queensland State of the Environment Report, 2017). This could be improved by progressing the extension to the World Heritage site, including previously assessed contiguous protected areas with World Heritage attributes (IUCN Consultation, 2020c), establishing corridors and working collaboratively with other adjacent land managers and Indigenous custodians.

Introduced animals include foxes (Vulpes vulpes), rabbits (Oryctolagus cuniculus), feral cats (Felis catus), goats (Capra hircus), wild dogs (Canis familiaris), feral pigs (Sus scrofa), feral deer (Cervidae spp.), feral horses (Equus caballus) and others.

Cats, foxes and dogs are widespread across the property. Predation by cats and foxes poses a significant threat to many ground-dwelling mammals and ground-nesting birds, while predation by dogs likely impacts larger macropods. The impacts of all three may be mediated by the extent and condition of habitat. NPWS manages wild dogs in accordance with the NSW Wild Dog Management Strategy. There is considerable interest in dingo conservation in Australia, including concerns about their genetic integrity and preserving their ecological roles. This strategy aims to promote a balance between managing wild dogs in areas where they have negative impacts and preserving their ecological roles elsewhere (NSW, 2022).

Large feral animals (deer, goats, horses and pigs) can have significant impacts on many natural ecosystems through selective grazing, overgrazing and trampling of vegetation, spreading weeds and pathogens, soil compaction and erosion, changes to nutrient cycling, and impacts on water quality. Feral pigs also prey on a broad suite of native fauna. Large feral animals likely occur at low densities in the Gondwana Rainforests reserves although some species can be abundant in some areas (e.g. horses and pigs on the Barrington Tops plateau).

Cane toads (Rhinella marina) are increasing in numbers in Border Ranges National Park. All these animals have an impact on the reserves either by displacement, predation or competition and their management is included in management plans (NPWS, 1998; NPWS, 2005; DERC, 2011). Straying stock (cattle, Bos taurus) pose a problem in some parts of the site (Chester and Bushnell, 2005). The introduced fish, plague minnow (Gambusia holbrooki), occurs in many streams. There are some locations where non-native sport fish (trout and salmon) are released into streams that flow into the reserves or the fish migrate upstream. The impact of these fish on native aquatic assemblages remains a matter for investigation.

Strategies to manage pest animals are guided by invasive species management plans in national parks. Controls are implemented in cooperation with neighbours as part of tenure blind approach to pest management through regional pest management strategies and plans in NSW (IUCN Consultation, 2017). Control priorities in national parks are determined based on risk. They consider potential and actual impacts on conservation, recreation, heritage and economic values, as well as biosecurity risks.

A controversial exotic invader is the European honey bee, which competes for nectar with native nectivores and occupies tree hollows that are used by native animals. A consequence of the wildfires of 2019-2020 was that in many locations the density of the vegetation was greatly reduced, which may have favoured introduced predators by compromising the capacity of the native animals to escape and seek shelter (Doherty et al. 2023). Vegetation recovery is now well progressed in most areas, and reduced vegetation density contributing to predation is unlikely to be a continuing consequence of the fires.

Climate change, resulting in increased average temperatures in all seasons, more hot days and warm spells with a substantial increase in the temperature reached on hot days, frequent and intense storms and flooding, and changes to the cloud base, mist availability, humidity or rainfall is emerging as one of the greatest challenges for the protection of Gondwana Rainforests World Heritage values (CSIRO, 2019). Climate change is also predicted to exacerbate other threats such as invasive species and pathogens, as well as fluctuations in rainfall patterns and altered fire regimes. In the Australian spring and summer of 2019-2020 extensive fires (51% surface area of the World Heritage site) was impacted in wild fires. The fires followed and were coincident with a prolonged drought (NSW DPIE, 2020; Dickman et al., 2020; DAWE, 2020). The Final Report of the NSW Bushfire Inquiry (DPC, 2020) stated that climate change clearly played a role in the extreme 2019/20 fire season.
Major flooding events occurred 2020, 2021, 2022 along the east coast of Australia. Impact assessment of the flood events on matters of national environmental significance, including the impacted World Heritage properties, and has informed prioritised responses (State Party of Australia, 2022). Ex Tropical Cyclone Alfred impacted Southeast Queensland and Northeast NSW with severe weather and flooding between 4 March and 31 March 2025. However, the OUV of the property was not heavily impacted and damage was restricted to visitor nodes, tracks and trails (IUCN Consultation, 2025).
NPWS finalised a climate change adaptation management plan for the World Heritage values of the Tweed Caldera group of Gondwana Rainforests reserves. The plan identifies actions to protect climate refugia, genetically rescue populations at risk and support the transition of habitats to maximise the conservation of biodiversity. Actions include fire management strategies to enhance protection of biodiverse climate refugia and establishing additional populations of native species in lower risk locations (IUCN Consultation, 2024).
The Australian Government National Environment Science Program (NESP) is funding a project to develop a climate change adaptation plan for focal culturally significant entities, threatened species and ecosystems of the Northern Rivers region in NSW which includes several of the Gondwana Rainforests reserves. The project is taking a co-design approach with First Nations organisations and involves consultation with multiple community groups, state and local governments to develop an online tool to assist with climate adaptation by local communities and governments (IUCN Consultation, 2024).