Biodiversity of the wetlands of the Kakadu Region, northern Australia

Abstract.

The biodiversity values of the wetlands in the Kakadu Region of northern Australia have been recognised as being of national and international significance, as demonstrated through their listing by the Ramsar Convention on Wetlands. Analyses of the wetland biodiversity have resulted in the production of species list for many taxa, and some population and community-level analyses of biomass and abundance, and the mapping of habitats at multiple scales. Wetland habitats include inter-tidal mud-flats, mangroves, hyper-saline flats, freshwater flood plains and streams. The tidal influence on the saline wetlands is pronounced, as is the influence of the annual wet-dry cycle of the monsoonal climate on the flood plains and streams. The vegetation is diverse and highly dynamic with rapid turnover of organic material and nutrients. The fauna is abundant with endemism being high in some habitats. Most fauna analyses have focussed on vertebrates with a large amount of information on waterbirds and fish in particular. However, despite extensive effort over the past two decades much is still unknown about the biota. While the invertebrate fauna in the streams has received some attention, a large taxonomic classification effort is required. The functional inter-relationships between habitats and species have largely not been assessed. Further, the ecology of many species is only cursorily known. At the same time there has been increased attention to pressures on the wetlands, such as weeds and feral animals, water pollution, and the potential impact of climate change and salinisation of freshwater habitats. Importantly, given the social context of the region, increased attention is being directed towards traditional use and management of the wetlands.