Recent Advances in Establishing Fish-Habitat Relationships in Lotic Systems: An Introduction

 

Identifying appropriate restoration and management strategies to conserve or recover fish population in streams requires predictions of how changes in stream characteristics result in changes of fish performance. We provide an overview of recent advances in data collection and analytical approaches that have potential to improve our understanding of the habitat requirements of fishes. We also provide a brief background of mechanistic and empirical modelling approaches designed to generate hypotheses and identify how fish respond to habitat characteristics such as flow, depth, food, temperature, and cover within a reach to riverscapes to regions.  We highlight some of these data collection techniques for both fish and their habitat that are currently employed in monitoring programs such as Integrated Status and Effectiveness Monitoring Program and the Columbia Habitat Monitoring Program.  In addition, we provide examples of how mechanistic models are used to inform the development of empirical models, which are in turn used to extrapolate site level information to the entire stream network. This example demonstrates the feasibility to implement and validate detailed mechanistic models as well as empirical approaches across massive scales.  Leveraging information from these kinds of monitoring efforts will increase our robustness of understanding and predictions for future applications.