Author(s): Matteo Roncoroni; Carole-Anne Gillis; Allen Beck; Rene Therrien; Normand Bergeron

Linked Author(s): Normand Bergeron

Keywords: Salmonid spawning; Hydraulic modelling; Hyporheic exchanges; Habitat modelling

Abstract: Salmonids often spawn at pool-riffle transitions or in proximity to in-stream structures. The functional explanation may lie in the intense hyporheic exchanges occurring at these specific locations and where eggs are buried. Despite this importance, spawning habitat models typically rely on depth and flow velocity, often leading to overestimates of habitat suitability. Here, we test whether integrating hyporheic exchanges into spawning habitat models provides suitability estimates that better capture habitat used for spawning. To do so, we combine drones, fully integrated surface-subsurface flow modelling, and conventional habitat modelling approaches. Our results align with our hypothesis and show that integrating hyporheic exchanges into spawning habitat models alongside depth and flow velocity provides suitability estimates that better represent observed spawning locations.

DOI: https://doi.org/10.64697/iahr.proc.ise2026.abs.251

Year: 2026