Abstract
The mitigating effects of fish passes to aid fish dispersal are well recognised; however, non‐sports fish species, juveniles and weak swimmers have mostly been neglected when developing solutions to fish passage issues. We studied the juvenile (fork length, FL Galaxias maculatus ), up an artificial ramp to evaluate the effects of fish size, ramp slope (5°, 15°, 25°), water velocity and the potential need for resting opportunities (pools) for a successful ascent. Water velocity significantly increased and fish passage success significantly decreased with ramp angle, with only one fish passing the 25° ramp. On average, fish had to be 10 mm larger to ascend a 15° ramp angle than at 5°. Pools did not enhance passage success in this study. To facilitate fish passage at barriers for weakly swimming fish species like juvenile īnanga, ramps should provide a rough surface substrate and have an optimal angle of 5° for a 3‐m ramp.