Measuring the Energetics and Physiological Status of Wild Fish Using Biotelemetry and Biologging Tools

For decades, animal ecologists have been interested in estimating the energetics and physiological status of wild animals in natural environments (i.e., outside of the laboratory).  With miniaturization of batteries  and innovations in sensor technology, there are now a suite of biotelemetry and biologging tools available for the study of a wide range of animals including fish.   Of particular relevance are devices that measure information related to locomotor (e.g., electromyograms, acceleration) or cardiac (e.g., heart rate) activity.  Here we summarize some of the tools that we believe are particularly relevant to the study of free-swimming fish including electromyogram radio transmitters, acceleration acoustic transmitters, tri-axial acceleration loggers, and heart rate loggers.  We discuss the benefits and limitations with each device and present brief case studies covering a range of fish including Pacific salmon, bull trout, lake sturgeon, and bonefish.  Although early studies using these tools focused on understanding the physiological ecology and environmental relations, increasingly they are being applied to address applied problems related to the cost of fisheries interactions, fishway passage, and hydropower activities.  We conclude by suggesting some of the management and conservation issues facing the Laurentian Great Lakes that could benefit from use of electronic tagging tools that enable the estimation of energetic and physiological status of free-swimming fish.