Wet Tropics of Queensland

The Wet Tropics exhibit exceptional natural beauty, with superlative scenic features highlighted by extensive sweeping forest vistas, wild rivers, waterfalls, rugged gorges and coastal scenery. This is particularly apparent between the Daintree River and Cedar Bay, where exceptional coastal scenery combines tropical rainforest and white sandy beaches with fringing offshore coral reefs. The winding channels of the Hinchinbrook Channel contain the most extensive mangroves in the region, providing a rich visual mosaic of rainforest and mangroves, and a terrestrial continuum with the Great Barrier Reef.

The Wet Tropics contains one of the most complete and diverse living records of the major stages in the evolution of land plants, from the very first pteridophytes more than 200 million years ago to the evolution of seedproducing plants including the cone-bearing cycads and southern conifers (gymnosperms), followed by the flowering plants (angiosperms). As the Wet Tropics is the largest part of the entire Australasian region where rainforests have persisted continuously since Gondwanan times, its living flora, with the highest concentration of primitive, archaic and relict taxa known, is the closest modern-day counterpart for Gondwanan forests. In addition, all of Australia's unique marsupials and most of its other animals originated in rainforest ecosystems, and the Wet Tropics still contains many of their closest surviving members. This makes it one of the most important living records of the history of marsupials as well as of songbirds.

The Wet Tropics provides outstanding examples of significant ongoing ecological processes and biological evolution. As a centre of endemism for the region (second only to New Caledonia in the number of endemic genera per unit area), the Wet Tropics provides fundamental insights into evolutionary patterns both in isolation from and in interaction with other rainforests. Its tall, open forests on the drier western margins of the rainforest are also significant as part of an evolutionary continuum of rainforest and sclerophyll forests. Eucalypts, that now dominate the Australian landscape, are considered to have evolved from such rainforest stock and radiated into drier environments from the margins of closed forests. The area supports an exceptionally high level of diversity of both flora and fauna, with over 3,000 vascular plant species in 224 families, of which 576 species and 44 genera are endemic, including two endemic plant families. Vertebrate diversity and endemism are also very high, with 107 mammal species including 11 endemic species and two monotypic endemic genera. In terms of avifauna, there are 368 bird species, of which 11 species are endemic. For reptiles, there are 113 species of which 24 species are endemic, including three monotypic endemic genera. The diversity of amphibians includes 51 species of which 22 are endemic.

The Wet Tropics holds a largely intact flora and fauna with hundreds of endemic species restricted to the property, of which many are classified as threatened. The majority of plant species have restricted distributions, and many monotypic plant genera and several species of marsupials, frogs and reptiles have very restricted distributions either as isolated or disjunct populations, reflecting the refugial nature of the rainforests found in several locations. The diversity of the plant communities and animal habitats of the Wet Tropics is recognised as being the most floristically and structurally diverse in Australia and is also outstanding on a global scale. Among many emblematic species occurring in the property is the flightless Australian cassowary, one of the largest birds in the world.

The Wet Tropic Management Scheme was established in 1990 with the signing of an agreement between the Australian and Queensland governments, who agreed to fund and coordinate the management of the Wet Tropics jointly. The Wet Tropics Management Authority (WTMA) was formed to look into the matters relating to the management of the property from the viewpoints of representative interest groups and the community at large. The management of the Wet Tropics is essentially at three levels. The State and Commonwealth Ministerial Council coordinates policies and funding (UNESCO whc.unesco.org). The WTMA is advised by the Rainforest Aboriginal Advisory Committee, Community Consultative Committee and Scientific Advisory Committee, which are responsible for general planning and policy development. The Queensland Environmental Protection Agency and Department of Natural Resources and Water manage the day-to-day aspects of the Wet Tropics (Department of Environment of Australia 2016).

On September 2020, the statutory Wet Tropics Management Plan 1998 was reviewed and released. A strategic plan has been formulated for 2020-2030, which aims to address priorities such as climate change and other threats; support the aspirations of Rainforest Aboriginal People by collaborating with them; and present the World Heritage Site to and collaborate with the tourism and partners and minimize impacts through appropriate management regimes (IUCN World Heritage Report 2020). The role of the Aboriginal People in the management of the natural and cultural heritage of the property is recognized by the Wet Tropics Act. The Wet Tropics World Heritage Area Regional Agreement 2005 provides for cooperative management of the property by 18 Rainforest Aboriginal People groups, the Authority and the Australian and Queensland governments (UNESCO whc.unesco.org).

Invasive species are a major threat to the property. These include feral pigs, yellow crazy ants, a number of invasive weed pests and pathogens such as myrtle rust. Invasive species along with climate change may result in catastrophic changes to the native flora and fauna and to the ecology of the region. There are over 500 species of weed, including some newly emerging ones, representing a threat to the integrity of the region. Proper mitigation measures need to be carried out for the eradication of these invasive species (IUCN World Heritage Outlook Report 2020). The yellow crazy ant is one of the major concerns, and several measures have been taken to eradicate it with the support of the Australian and Queensland government (IUCN World Heritage Outlook Report 2020). Setting out insecticidal bait with fipronil (a neurotoxin with broadscale effects) has proved to be a successful eradication measure against the yellow crazy ant (Gibbons et al. 2015; Overmyer et al. 2007). Now the park has three confirmed eradicated sites (IUCN World Heritage Outlook Report 2020).

Timber industries were booming within the boundaries of the property before the Wet Tropics were declared a World Heritage Site, which caused much forest loss. Approximately 6535 tracks in the property were prohibited for vehicle use earlier, as these were used by the timber industries (Australian National Periodic Report Section II); now these tracks are used as walking tracks in the property like the long-distance Misty Mountains trails. There is no documented deforestation after 1991 (Reside et al. 2017).

According to the WTMA (2019), "Climate change is one of the most significant threats to the Area which is likely to result in widespread and substantial ecological change". Climate change is escalating as the most significant threat in the Wet Tropics of Queensland (IUCN World Heritage Outlook Report 2020). The biodiversity is threatened due to changes in the climatic patterns. Climate change is also associated with risks of extreme weather events and increase in the intensity of cyclones and floods (Krockenberger et al. 2004). Cyclones occur commonly here, but due to changes, caused by fragmentation, other anthropogenic activities and invasive species, in the ecosystem, the adaptive capacity has reduced considerably. An increasing population and rising numbers of visitors are also responsible for creating extreme pressure through an increasing demand for infrastructure such as roads and dams and for energy. This pressure is a threat to the protection of the site (IUCN World Heritage Outlook Report 2020).