An International Union for Conservation of Nature risk assessment of coastal lowland rainforests of the Wet Tropics Bioregion, Queensland, Australia

Abstract

AbstractLowland rainforest communities are among the most threatened across South‐east Asia as a result of ease of access, suitability for agriculture and proximity to population centres along the coast and to ports for export of timber, minerals and agricultural produce. In Australia, coastal lowland rainforest occupies a narrow band between the marine‐influenced littoral communities and the forests of the coastal ranges and uplands in the Wet Tropics Bioregion of north‐east Queensland. As the coastal lowlands were already highly fragmented, and subject to ongoing conversion for agriculture and urbanization, they were excluded from the World Heritage listing of the Wet Tropics of Queensland in 1988. Littoral rainforest and broad‐leaved tea‐tree swamps in the coastal zone have both recently been protected under Commonwealth environmental protection legislation; meanwhile, the remnant coastal lowland rainforest faces continued threats from extreme events, climate change, land management activities and introduced species. In a risk assessment based on IUCN guidelines, coastal lowland rainforest was assessed as endangered due to restricted distribution (full extent of the community encompassed by a minimum complex polygon less than 20 000 km2) in conjunction with qualitative evidence of disruption to biotic interactions. A second criterion related to the historic decline in geographic distribution (60% decline in distribution since 1750) would correspond to a condition of vulnerable. Coastal lowland rainforest on alluvial soils has been particularly impacted, and a 75% decline in distribution since 1760 would correspond to a condition of endangered for this subtype. We had insufficient data to address the remaining IUCN Red List criteria for ecosystems, but point to published studies which address these criteria at the subregional level, and make suggestions for future data collection, monitoring and analyses which may support future reviews or proposals for enhanced protection within an Australian legislative context.