Fish movement upstream through a central Queensland (Fitzroy River) coastal fishway

Abstract

A two-part study was made of fish movement past the Fitzroy River barrage at Rockhampton. Queensland. to assess the feasibilities of routes other than that through the simple pool and weir fishway situated at the barrage, and to monitor fish passage upstream through the fishway by placing a V-trap cage immediately above the fishway exit.

Neither of the alternative routes to the fishway, namely via the inundated floodplain or under open barrage gates, appeared to be feasible pathways for fish to move to areas above the barrage. Sixteen species of fish over a relatively wide size range were found to pass through the fishway. Greatest species diversity. and rates of passage of particular species, occurred in the summer months. Variation in levels of the tidal tailwater and the headwater, which could be controlled to some extent by raising or lowering the barrage gates, influenced the numbers, sizes and species of fish passing through the fishway. It is concluded that while there is a need for facilitating fish movement upstream past the barrage. the present fishway does not seem to be particularly effective in this regard. Structural and management changes to the fishway which may improve its efficiency are proposed.