Oral Presentation International Conference on River Connectivity (Fish Passage 2018)

Fishways and PIT reader systems: demonstrating the restoration of longitudinal connectivity in the Murray River, Australia. (#117)

Matthew J Jones 1 , Lee Baumgartner 2 , Brenton Zampatti 3 , Karl Pomorin 4 , Ivor Stuart 5
  1. Department of Environment Land Water and Planning, Heidelberg, VIC, Australia
  2. Charles Stuart University, Albury
  3. South Australian Research and Development Institute (Aquatic Sciences), Adelaide
  4. KarlTek Pty Ltd, Melbourne
  5. Kingfisher Research and Consulting, Melbourne

In the Murray River, Australia, longitudinal connectivity was compromised by the construction of dams, weirs and regulators, during the early-mid 1900’s.  To re-establish the longitudinal movements of fishes along the Murray River, 14 fishways were constructed as part of the ‘Sea to Hume program’.  To evaluate fishway success, a large-scale integrated passive integrated transponder (PIT) reader system was implemented across all fishways along the Murray River upstream of Lock 1.  We analysed 11 years of fish movement data to document the extent of long distance migrations.  A total of 4,373 fish (18% of the total PIT tagged population) were recorded by the PIT reader system, with approximately 17% of these undertaking multi-site (multiple fishway) journeys, with some fish moving through six different fishways.  Mean movement distances for those fish undertaking multi-fishway journeys were 116.3, 163.9, 208.5 and 352.5 km for Murray cod, golden perch, carp and silver perch, respectively.  Maximum movement distances recorded for Murray cod, golden perch, carp and silver perch were 497, 1556, 1713 and 1556 km respectively.  These data demonstrate fishway construction restored long distance migrations along the Murray River, particularly during low-medium flows, when the weirs remain in place.  Completion of the ‘Sea to Hume’ fishway program has achieved its aims of reducing the impact of instream barriers on fish movement and reinstating longitudinal connectivity.  Reconnecting 2,235 km of the Murray River for native fish passage therefore, represents one of the largest successful river restoration programs in the world.