Example gray whale tracks from visual, acoustic, and infrared localizations. Visual sightings are shown with coloured circles, acoustic calls are shown with coloured triangles, and infrared blows are shown with coloured diamonds. Colour indicates the amount of time in minutes since the start of the detections. The left plot spans 06 January 2015 02:14:15–02:55:10 local time (at night so no circles for visual sighting locations are plotted) and the right plot spans 07 January 2015 08:31:01–09:10:58 local time. Four black triangles indicate the positions of hydrophones, the black circle indicates the location of the visual observers, and the white diamond indicates the location of the infrared camera. The visual field of view is shown with yellow lines (with black dotting) and the infrared field of view is shown with pink lines. The black contour lines show the seafloor depth in 20 m intervals (from the NOAA National Centers for Environmental Information’s Southern California Coastal Relief Model with 1 arc-second resolution). Latitude limits are 36.40°–36.45°N and longitude limits are 121.92°–121.97°W.