Automatic telemetry to monitor the activity of limpets and sea level oscillations

A new version of a technique, based on telemetric devices, to monitor tempo ral aspects of the activity of homing species of limpets and the parallel r ecording of sea level oscillations is described. The home/away status of in dividual limpets was continually assessed by means of a magnetic reed switc h. Signals from the reed sensors were transmitted to a distant automatic sc anner/receiver, located away from the shoreline. The system can be easily r eplicated and employed for extensive long-lasting monitoring in the field, even in those cases where previous versions, based on cable connections, we re unsuitable.