This video documents juvenile common galaxias (Galaxias maculatus) or whitebait trying to move up into freshwater after spending several months developing at sea. Within 50 metres of the coast they encounter their first obstacle, the sheer concrete wall of a drainage culvert. Some species of Galaxiids are renowned climbers and can climb slippery walls 10's of metres high; not so the common galaxias. It relies on a short burst of speed – burst swimming – against a vertical flow of water to try and overcome obstacles like this. In this video you can just make out fish rapidly pushing their way up in the flow forming little V's. At times they seem to go up like little squadrons. A few make it, some rest half way before falling back, and others seem to be able to rest up while stuck on the rock face, before pushing on.
This highlights the need for fishways or fish passage to be included in initial culvert designs, or allowances made for retrofitting them to existing structures. As shown in the video, even minor works can pose insurmountable barriers too some species



Filmed at Dunns Creek on the Mornington Peninsula in Victoria, Australia.


© Greg Wallis 2021

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