Cuvier's beaked whales can reach lengths of about 15 to 23 feet and weigh 4,000 to 6,800 pounds. they hold the record for the deepest and longest dive for any mammal. They are especially vulnerable to intense noise created by military sonar. They suffer decompression sickness, or ‘the bends’, if they are frightened or panicked by man-made noise and surface too quickly.