Rivers and estuaries are important components of the ecosystem providing habitat for many fish, aquatic invertebrates, birds, amphibians and reptiles. Estuaries are places of transition from freshwater to seawater and are subject to marine and freshwater influences. The health or condition of rivers, estuaries and associated vegetation communities can be negatively impacted by increasing salinity, sedimentation, pollution, removal and destruction of instream habitat, and altered flow regimes. These threatening processes can impact on the fauna directly, through toxic effects, or indirectly, including by the loss of suitable breeding, sheltering and feeding sites and isolation of populations due to loss of water connectivity between floodplains and river systems. Restoration of aquatic habitats aims to return these systems back to a natural state and minimise threats.