Fish Habitat Mapping

Abstract

NSW Department of Primary Industries and Regional Development (DPIRD) Fisheries and Forestry was engaged by the NSW Department of Climate Change, Energy, the Environment and Water (DCCEEW), Biodiversity, Conservation and Science (BCS) Group to conduct a field survey to undertake fish habitat mapping along the Lower Mehi River (the project area) in the Gwydir Catchment, as part of the Gwydir Reconnecting Watercourse Country Program (NSW DCCEEW 2024)1 . The objective of the work was to address gaps in ecological knowledge and improve understanding of the environmental assets that exist in the lower Mehi River. This will aid in the management of flows down the system to restore fish communities in this river. The main objectives of this project included the following:  Document the riparian features of the identified reaches of the Mehi River, focusing on native vegetation, weed infestation and existing management activities  Document the stream bed morphology including the location, length and depth of pools that may act as drought refugia; and instream habitat features including large woody habitat (LWH) or snag loading  Calculate commence-to-inundate flow thresholds of select habitat features where feasible including benches, wetland entry/exit points, large woody habitat and rootballs/bank overhangs  Identify and map threats and processes that may influence the extent and condition of aquatic and riparian habitat features  Make recommendations to protect and improve river health, threatened species habitat enhancement, weed control, and other habitat features