Analyzing fish leaping and movement potential at a migratory barriers: Michigan 2022-2025

The enclosed Matlab scripts and supporting files are used for fish passage assessments at small migratory barriers with complex geometry. Building upon a 2-D ballistic trajectory mathematical model, the model incorporates field-derived behavioral parameters and simulated flow data to evaluate the likelihood of successful leaping attempts. The model integrates stochastic variation in key fish characteristics—such as body length, launch speed, and leap origin—to simulate a range of realistic leaping scenarios. These are coupled with three-dimensional, CFD-derived inputs for local water velocity and depth, enabling a spatially detailed assessment of hydraulic conditions that are most conducive to successful passage. This integrated approach provides a more comprehensive and biologically informed evaluation of passage potential at migratory barriers. To demonstrate its utility, the model is applied in a case study examining the influence of complex barrier geometry on fish passage outcomes, highlighting its potential to inform engineering design decisions that either facilitate or limit fish movement based on management objectives. The enclosed files are associated with steelhead passage at a arc-labyrinth and low-flow weir at the FishPass project, located on the Boardman/Ottaway River, MI, USA.