Fish Passage Failure & Fix Video

August 20, 2026

Hi everyone,

Tim Olley has shared a short video that clearly captures weak-swimming inanga/common galaxias (Galaxias maculatus) struggling – and ultimately failing – to pass through a culvert with fast, laminar-type flow.

The second half of the video shows the same culvert post-baffle installation: velocities are reduced and rest pools are created, giving the fish the breaks they need to make it through.

This footage was captured as part of a research project investigating the swimming ability of small-bodied fish.

Enjoy!

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