Some of the world's most beautiful, intelligent and highly adapted mammals inhabit our seas and oceans, and have stirred the human imagination for many centuries. As our knowledge of marine mammals grows, the need exists for a reliable and complete reference to the ecology and biology of these fascinating creatures. The Handbook of Marine Mammals series was founded with this in mind and now reaches its conclusion with this sixth and final volume. Within the pages of this classic series, scientists, conservationists and informed layperson alike can find the definitive review of all the world's whales, dolphins, porpoises, seals, sea lions, and related species as well as sea otters and sea cows.Volume 6 covers the remaining dolphins and porpoises in a series of 17 chapters, each written by a specialist author with extensive personal research experience of the species. Each chapter provides a description of the species, and includes sections on the aspects of distribution and abundance, anatomy, physiology, behavior, reproduction, parasites and diseases and the impact of human activity on the animal's population and well-being. Numerous maps, photos and drawings illustrate the text.