May 1, 2005
A miniature computer weighing less than 5 ounces attached to the backs of beaked whales with suction cups is providing new clues to the behavior and sounds made by the deep-diving reclusive species. Little is known about these mid-sized toothed whales except that they have been involved in a number of mass strandings in recent years and may be sensitive to sonar used by the navies of the world. The D-tag, or digital tag, was developed by biologists and engineers at the Woods Hole Oceanographic Institution (WHOI) to record soundsnot only the sounds made by the tagged whale but also sounds from other whales, noises from boats, sonars and other sound sources in the area. It has recorded dives 90 minutes long and as deep as 2,000 meters (about 6,000 feet), including the deepest dive recorded by a tag on any mammal. Recordings of Cuvier’s beaked whales and Blainville’s beaked whales in the Canary Islands and off Italy show they make clicks like dolphins and sperm whales and fi nd their prey by echolocation. More results will be presented at the joint Acoustical Society of America and Canadian Acoustical Association meeting in Vancouver, British Columbia in mid-May. Learn more about the D-tag in Oceanus Magazine Vol. 43 No.2, Playing Tag with Whales.