April 15, 2015 - On a recent expedition aboard thevessel in the Gulf of Mexico off the Louisiana coast, researchers got a giant surprise. As they viewed footage streamed by theremotely operated vehicle (ROV), a sperm whale swam into the frame and proceeded to circle around the ROV multiple times. The ROV was operating at 1,962 feet (598 meters) below sea level.Click here to read more:Video courtesy Ocean Exploration Trust/GISR