Evaluating Juvenile Salmonid Physical Habitat Use and Characteristics Using A Spatially Explicit Bioenergetics Model And Remote Underwater Video Surveys

Date

2018-09-11

Authors

Tweedie, John

Journal Title

Journal ISSN

Volume Title

Publisher

University of Guelph

Abstract

Understanding physical and biotic aspects of juvenile salmonid habitat is imperative to conservation and restoration efforts. Empirical weighted usable area (WUA) models have been widely adopted to assess riverine habitat suitability but suffer from over-generalized and non- transferable outputs. Directly linking biophysical conditions to metabolic responses using bioneregetics models allows highly transferable growth rate potential predictions. A coupled hydraulic and drift foraging bioenergetics model was applied to two Credit River reaches to assess the influence of channel structure on salmonid habitat. Boulders in the mid-channel sections were observed to increase flow heterogeneity and create velocity refuge and favourable feeding gradients in their wakes. Model output comparison to fish distribution data, generated using remote underwater video (RUV) techniques, indicated that fish using near-bed shear zones as refuge and vertical velocity gradients for feeding was an important behaviour discounted when utilizing depth averaged hydraulic model data.

Description

Keywords

bioenergetics, hydrology, fluvial geomorphology, ecology, Atlantic Salmon, salmonid habitat, River2D

Citation