Northern region << BACK TO CONTENTS Coordinating environmental flows across three major rivers wooed native fish hundreds of kilometres into Victorian waterways in 2017. Native fish such as golden and silver perch can be found across a large area of the River Murray and its tributary rivers. However, breeding often occurs at ‘hot-spots’ – where conditions are just right for a large successful breeding event. This results in very large numbers of juvenile fish in one area that are looking for triggers to move to new homes right across the river system. In 2016-17, monitoring of native fish in the mid-River Murray showed large numbers of juvenile golden and silver perch. Waterway managers, scientists and river managers set Wentworth South Australia Mildura Mulcra Island floodplain Hattah Lakes VIC Barmah 2. Flows were then released across the Goulburn and Campaspe rivers to encourage fish to move into these rivers. Echuca i v e r 1. The Murray-Darling Basin Authority and the NSW Government first released water for the environment along the River Murray to encourage fish to move. 81 | Victorian Environmental Water Holder NSW River M “The movements into the Goulburn generally coincided with river flow increases, and movements back out into the Murray tended to coincide with flows falling,” said Simon. NSW used water for the environment to boost fish numbers to encourage their movement along the lower Darling River in 2016-17. themselves a challenge to encourage these fish to migrate from the River Murray and set up home in the Goulburn and Campaspe rivers. They also wanted to learn more about how to increase fish populations throughout the Murray–Darling Basin. First, they delivered water for the environment down the River Murray to stimulate golden and silver perch to move upstream through the fishway on Torrumbarry Weir. They then delivered water for the environment to the Goulburn and Campaspe rivers to encourage the fish in the Murray to move up into those rivers. The plan worked. Monitoring showed that juvenile golden and silver perch tagged at Torrumbarry Weir moved up into the Victorian rivers directly in response to the flows delivered. While some fish eventually returned to the Murray, others stayed put to hopefully call the Goulburn or Campaspe rivers home. Goulburn Broken CMA Environmental Water and Wetlands Manager Simon Casanelia said the project provided lots of information to help improve native fish management with environmental water. Indicates water flow C a m p a s p e D R i v r a r e L u r G u o w wer l e C g r e n B o r k i n r e G e k Cree u v er urray R l k o i R nbo b n
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