Individual Variation in Philopatry Is Unrelated to Activity and Space Use in the Undulate Skate Raja undulata

Individual variation in behavior is widespread in animals. Movement traits, which describe how individuals interact with their environment, can vary across a range of spatial and temporal scales. Much research has focused on understanding individual variation in movements at large spatio-temporal scales, such as migration and dispersal, which are driven by, for example, size, age, feeding strategy, and reproductive needs. Recently, bio-logging revealed individual variation in traits at finer scales that respond to day-to-day motives (e.g., foraging, predator avoidance) such as activity, chronotype, or space use. As traits operating at different scales may respond to different mechanisms, an important yet unresolved question is whether behavioral traits covary across spatial and temporal scales. Answering this may shed light on fundamental aspects of behavioral variation and regulation in animals. We addressed this gap by acoustically tracking 179 individual Raja undulata over four years in a coastal archipelago in NW Spain. Using daily presence-absence data, we classified individuals into three philopatry patterns: continuous residency, seasonal residency, or site fidelity. We then used a multivariate mixed modeling approach to explore how activity space size (km²) and activity rate (m/h) varied among individuals and their relationship with philopatry patterns. We found that activity and space use covaried and were consistently different among individuals but were unrelated to philopatry, suggesting that they represent independent axes of behavior. We highlighted that behavioral variation might carry eco-evolutionary implications through selection, with selective pressures acting on philopatry being unlikely to drive co-evolution of activity or space use.