Developing biological indicators for the assessment of environmental flows

Recent reviews of the principles underlying the management of large rivers stress the need for a better understanding of the relationships between elements of the flow regime and ecological processes.¹,² Many authors have focused on the reinstatement of elements of the natural flow regime as a goal for river restoration.³,⁴ The New South Wales Government's Water Reforms have addressed this issue through the implementation of environmental flows in seven regulated river systems, with the aim of reducing the impacts of water regulation and extraction by mimicking elements of the natural flow regimes.⁵ Determining the ecological responses to environmental flows is paramount in assessing the effectiveness of managed flows for restoring riverine ecosystems.