Beaked whales are the members of the family Ziphiidae, which consists of 23 species. These toothed whales are distinguished by their elongated beaks. Among air-breathing animals, beaked whales are some of the most extreme divers: Cuvier's beaked whales regularly dive for an hour at a depth over 1,000 m (3,300 ft), and the longest and deepest foraging dive recorded is 137. 5 minutes at 2,992 m (9,816 ft). This is the greatest dive-depth known for a mammal.