Monitoring the Three-Dimensional Movement of Multi-Species Assemblages in a Modeled Environment Using Acoustic Tag Technology: Results from 2011 AFS Seattle FISH Fest!

Several acoustic tagging systems currently available generally provide only tag presence within the detection range of the acoustic tag receiver.  With these tagging systems it is difficult to achieve target position estimates more precise than approximately ± 10 meters, even with sophisticated multiple hydrophone deployments.  The lack of spatial resolution in these systems is a result of their tag detection and identification methodologies which allow high rates of tag collisions, false positives, and lower signal-to-noise ratios.  A tagging system that utilizes a methodology which minimizes these problems was used to track three-dimensional positions of several species of fish at San Francisco’s Steinhart Aquarium in 2007 and at the Seattle Aquarium during the 2011 AFS Fish Fest!  Coho salmon (Oncorhynchus kisutch), canary rockfish (Sebastes pinniger) and Yellowtail Rockfish (S. flavidus) were acoustically tagged in September 2011 at the Seattle Aquarium and alligator gar (Atractosteus spatula) in September 2007 at San Francisco’s Steinhart Aquarium.  The tagged fish were tracked in three-dimensions in real-time and tracks were displayed as they travelled throughout the aquariums.  Various results will be presented including the three-dimension paths and comparisons between the individual fish tracks and species behaviors.  This high precision, three-dimensional monitoring of multi-species assemblages has application beyond the modeled environment.  Current research needs require improvements in the ability to investigate the ecology of marine and freshwater populations on both large and small spatial scales, to examine issues such as physical impacts of structures, species-specific interactions, siltation effects, and invasive species.  Resolution of fine-scale animal movement and interactions is particularly important for studies of the effects of coastal structures such as oil platforms, hydrokinetic. and wind turbine installations.  Habitat studies in other near-shore environments, including Marine Protected Areas (MPAs), coral reefs, and sea-grass beds, would also benefit from the ability to investigate species-specific behavior and distribution with high precision.