3. Ecosystem health

Woodlands are areas of mature, single-stemmed trees that have between 20 and 50 per cent canopy cover, whereas forests have greater than 50 per cent canopy cover. Woodlands and the woodland understory reduce flood risk by slowing overland water velocity and thereby regulate sediment and nutrient supply to the Reef.⁹⁵⁹ Forests contribute to the hydrological cycle through evapotranspiration, cloud formation and rainfall generation.⁹⁶¹ Pisonia forests provide critical seabird nesting habitat and help to stabilise sediments on coral cays within the Region.⁹⁶²

Since 2019, the Cape York and Wet Tropics regions have the greatest extent of remaining remnant woodlands and forest ecosystems, at approximately 88 and 99 per cent of the extent before European settlement, respectively. The Fitzroy region has the lowest 8 percentage of remnant forest in the Catchment at approximately 32 per cent and the Burnett Mary region has 36 per cent of remnant woodland extent compared to pre-European settlement.¹¹⁰

Climate change has increased the extent of burned areas and the frequency of fires, including forest megafires (those that burned more than 10,000 square kilometres), over the past 4 decades.⁹⁶³

The extent of historical habitat loss differs between regions, and more remnant habitat remains in northern regions than elsewhere. The extent and condition of woodlands and forests continue to be affected by land clearing and forest fires. Overall, annual clearing rates have reduced in recent years, but vary among regions.