Integrating physiology into movement ecology of large terrestrial mammals

Movement paths are influenced by external factors and depend on an individual's navigation capacity (Where to move?), motion capacity (How to move?) and are ultimately driven by internal physiological state (Why move?). Despite physiology underlying most aspects of this movement ecology framework, the physiology-movement nexus remains understudied in large terrestrial mammals. Within this Commentary, we highlight the physiological processes that underpin the movement ecology framework and how integrating physiological measurements can provide mechanistic insights that may enhance our understanding of the drivers of animal movement. We focus on large terrestrial mammals, which are well represented within the movement ecology literature but are under-represented in movement studies that integrate physiological state. Recent advances in biologging technology allow for physiological variables, such as heart rate and body movements, to be recorded remotely and continuously in free-living animals. Biologging of body temperature may provide additional insights into the physiological states driving movement. Body temperature not only provides a measure of thermal stress, but also an index of animal wellbeing through quantification of nutrition, hydration, reproductive and disease states that may drive animal movements. Integrating measures of body temperature with fine-scale GPS locations may provide insights into causality and improve our mechanistic understanding of animal movement, which is crucial for understanding population performance and monitoring reintroduction success. We recommend that baseline studies are undertaken, linking animal movement to the underlying physiological mechanisms, to allow for the development of realistic predictive models to improve conservation efforts in the Anthropocene.