On the use of telemetry in habitat selection studies

Abstract

Understanding the relationships between organisms and their habitat is a central question in ecology. The study of habitat selection often refers to the static description of the pattern resulting from the selection process. However the very nature of this habitat selection process is dynamic, as it relies on individual movements, which are affected by both internal components (i.e. related to the animal itself, such as its behavior; foraging, resting, etc.) and external components (i.e. related to the composition of the environment). Coupling habitat selection and movement analyses should thus provide new insights into the proximal mechanisms and evolutionary causes of animals’ space use. To achieve this, the introduction of GPS technology in the early 1990s showed great promise, as it facilitates tracking of animals with high fix frequency over long time periods. From a statistical point of view, this led to an increased temporal autocorrelation in the positions of successive locations. Whereas classic approaches of habitat selection often relied on the assumption of statistical independence between relocations, the development of newer methods has made possible the use of autocorrelation for more dynamic approaches. As several statistical tools are now available for researchers, autocorrelation can be incorporated successfully into the analysis, instead of being removed or even ignored. We emphasize the need to integrate individual behavioral mechanisms in habitat selection studies. The use of GPS technology in wildlife management issues is, however, often motivated by its technological advantage to produce large amounts of data, rather than biological questions. We warn users of GPS devices about the statistical and conceptual changes induced by this technology used for studying habitat selection. We encourage a solid biological reflection about the ecological characteristics of studied species and spatial and temporal scales considered, before deciding on which sampling protocol and which telemetry technology to use in accordance with the biological question of interest.