Clearing of vegetation and livestock grazing in the Hughes Creek catchment (central Victoria, Australia) has resulted in substantial sand inputs. This has led to loss of instream vegetation and infilling of pools and rocky riffles that provide essential habitat for the nationally Endangered Macquarie Perch (Macquaria australasica). Degradation of these habitat features has likely contributed to population declines.
Instream revegetation has potential to stabilise sediments and improve habitat for invertebrates and fish; however plant establishment is often limited by unpredictable flow events during early growth stages. To improve reliability, we trialled an approach integrating targeted species selection, alternative growing formats, and strategic timing and placement of planting.
Nine locally indigenous species possessing rhizomes and stolons were selected for their capacity to colonise and bind sand and recover following disturbance. Planting methods were designed to reduce uprooting during high flows and promote rapid establishment. Species were planted across terrestrial, fringing and inundated zones according to inundation tolerance, with aquatic and fringing species established during low summer flows and terrestrial species planted later under higher soil moisture conditions.
One year after planting, all species persisted and total plant cover increased substantially across all zones, particularly in fringing (3.9% to 45.6%) and inundated areas (to 41.6%). In contrast, unplanted control areas showed limited increases and no colonisation in the inundated zone.
These results demonstrate a promising approach for restoring instream vegetation; however further monitoring is needed to assess longer-term success and benefits that revegetation provides for sand stabilization and native fish populations.