This guide covers native and alien fish that are known or expected to occur in the cotton growing Macquarie – Barwon region of northwest NSW, focussing on the Gwydir, Namoi and Macquarie river valleys. The region is bordered by the rugged Warrumbungle, Nandewar and Great Dividing ranges, whilst the lowlands are dominated by fertile alluvial floodplains. Each distinct landscape area provides a diverse array of habitat for native fish species.
The north west region of NSW is dotted with lagoons and billabongs and dissected by red gum-lined rivers. Major waterbodies include the Gwydir, Mehi, Namoi and Macquarie rivers and the Ramsar listed Gwydir wetlands and Macquarie Marshes. Flow regulation of these systems is provided by Copeton Dam in the north, Mollee, Gunidgera and Weeta weirs on the Namoi, and Burrendong Dam in the west. Extensive areas of the region are devoted to the production of cotton on the floodplains, and grazing practices in the riparian and woodland communities.
