This new edition of Marine Mammals of the World describes and illustrates newly discovered and rarely photographed species, making it the most comprehensive and up-to-date identification guide available. This edition continues to meet the research-focused needs of marine biologists and conservation biologists by providing a tremendous influx of new photos, taking advantage of advances in digital and auto-focusing photography, and the emergence of marine mammal studies and -whalewatching- around the world. The book encompasses cetacean, pinniped, and sirenian species, as well as extinct species, and describes basic biology and taxonomic groupings of marine mammals. Contains superb photographs of every species of marine mammal for accurate identification Authors possess nearly 80 years of collective experience with almost all of the species and distinctive geographic forms described in the guide Provides the most detailed and anatomically accurate illustrations currently available, including more than 750 new illustrations Special emphasis is placed on the identification of species in -problem groups, - such as the beaked whales, long-beaked oceanic dolphins, and southern fur seals Includes a detailed list of sources for more information Contains updated taxonomy including four new species.