Identifying Hydraulic Preferences of Riverine Fish, Using Fine-Scale Fish Tracks and Hydraulic Data

Rivers worldwide are becoming increasingly changed by human activities. Barriers, such as dams, are a frequent feature in rivers and have many impacts, from altering river hydraulics to impeding fish migration. Hydraulic conditions around a barrier and pass may be very different from natural systems and confuse approaching fish as they attempt to pass. Advancing technologies such as fine-scale 2D acoustic telemetry and computational fluid dynamic models have led to a wealth of data on fish movement and corresponding hydraulics in rivers. Such data can be analysed to determine fish habitat preference—whether fish avoid or prefer certain environmental conditions. Two approaches for analysing habitat preference are resource selection functions and step selection functions. Both methods statistically analyse habitat usage patterns of animals. In this paper, we provide an overview of the approaches and a brief review of their limited applications so far in riverine environments. With increasing data accumulation on fine-scale habitat usage of riverine fish, habitat preference analysis is a promising tool for identifying hydraulic preferences of migrating fish.