Locomotor activity patterns of permit Trachinotus falcatus as an indicator of habitat function in the Florida Keys, USA

Understanding the functional role of habitats to wild animals can aid in implementing management actions to protect critical habitat from anthropogenic threats. However, habitat function is challenging to measure across extensive space and time, particularly in marine systems. We used acoustic telemetry tags equipped with tri-axial accelerometer sensors to track the movement and locomotor activity of permit Trachinotus falcatus in coastal marine habitats of the Florida Keys (USA) so that we could remotely characterize their behavioural ecology and infer habitat function. Recent research in this system explored space use by permits and identified shallow seagrass flats and offshore reefs and wrecks as important foraging and spawning habitats, respectively. Predictive models applied here identified variation in permit activity patterns across a diversity of spatial (i.e. habitat type and site) and temporal (e.g. time of day, lunar phase) factors as well as complex interactions. Based on known permit behavioural ecology, peaks in activity in the late afternoon to evening at putative spawning sites were used to infer the spatial-temporal dynamics of likely spawning activity. This spawning signature was observed at 8 offshore reef locations, with considerable seasonal variation amongst sites. Timing of spawning may therefore vary among sites, while the functional role of some sites likely extends beyond spawning (e.g. staging, foraging). These data provide insights into permit spawning sites and behaviour and highlight the potential for acoustic telemetry equipped with acceleration sensors to generate knowledge relevant to habitat and fisheries management.