Collecting, interpreting, and merging fish telemetry data from an AUV: Remote sensing from an already remote platform

Chemical and hydrological AUV sensors (e.g. C, T, 02, CDOM, Chlorophyll a) collect information about water in contact with or in close proximity to the vehicle. Sonar (e.g. ADCF, side scan, dual beam, and multibeam) collect data about features distant on the scale of tens of meters away and linked to coordinates. In contrast, acoustic tags implanted in fishes or other marine fauna can be detected at distances greater than a kilometer away, which brings special considerations to data treatment and merging. In the case of telemetry systems that log sound pressure levels, relative signal strength can be used to produce proximity maps using regression. For systems with invariant signal timing, a synthetic aperture engine can calculate location of the tag if a suitable AUV path produces a good aperture. In the common case where both of these conditions are lacking, the tag position must be assigned to a place along the vehicle's path. The use of tags that broadcast information from their own sensors (e.g. pressure, temperature) can help resolve both the position and environment of the distant tag. An empirically-fashioned hierarchical decision matrix based on numerous AUV-fish telemetry missions in shallow and deep (3m to 600m) water assists in mission planning, data processing, and displaying AUV-collected data about telemetered fauna and their environment.