Application of controls in separating behavior of temperate reef fish from environmental interference in an acoustic telemetry study

This study aimed to describe the behavior of temperate reef fish after accounting for potential effects of environmental variability on detection range in long-term telemetry. The study was conducted in Gray’s Reef National Marine Sanctuary. Seasonal (likely due to stratification), short-term cyclic (tidal), and episodic (storms) variability was observed in stationary control tag detections. Orientation (angular distance between the transmission line and the flood/ebb tidal current axis) and linear distance between the tag/receiver pair also altered control tag detections with respect to the tidal cycle. Fish detections exhibited diel variability and presence/absence patterns attributable to behavior. Variability with the seasonal and tidal cycles was also observed that could not be differentiated from environmental interference. These results suggest that control tags are useful for differentiating animal movement from environmental variability in open water marine acoustic telemetry studies.