River dredging helps boost wildlife











Scientists monitoring the health of the Avon River have unexpectedly found a number of native fish species. The surveys were part of work to determine the impact dredging, or the removal of sediment from river pools, was having. The work was funded by State NRM and undertaken by Wheatbelt NRM and the Department of Water. The DOW’s Avon Program Manager Michael Allen said clearing sand from the bottom of three permanent water pools had helped boost native wildlife populations and improve water quality. “Early results indicated an unexpected number of native fish species including the Western Minnow, Night fish and Western Pygmy Perch,” he said. “Generally people consider the Avon to be fairly degraded in terms of water quality, so we hadn’t anticipated finding this many fish. “The fish sampling was done using nets and fish traps at either end of the pools to capture the fish as they moved through the river. “There were also a large number of long neck turtles, and with further monitoring, we’re expecting to find even more native wildlife.” The surveys over the past 12 months have focused on Katrine Pool downstream of Northam, Reserve Pool near Beverley and Gwambygine upstream of York. A long reach excavator was used to remove 42,000 tonnes of sediment from the three pools. Wheatbelt NRM’s Natarsha Woods said dredging had become necessary because of mistakes made in the past. “The deliberate deepening of the river floor in the 1960’s to prevent flooding and the removal of vegetation has accelerated erosion,” Natarsha Woods said. “This had allowed sediment to be washed into permanent river pools, making them too shallow or filled in completely. “Dredging over the last decade has helped restore the pools, giving native wildlife a permanent water source and a drought refuge.” Media contact: Natarsha Woods, Wheatbelt NRM 9690 2250 or 0428 927 052