Amazon.com description: Product Description: "Prior to this contribution nearly everything known of the behavior of marine mammals came to us from their activities on land, the laboratory, or occasional surface sightings. As a group, these animals dive to feed, yet most aspects of their behavior while submerged remained a complete mystery. Due, in large part, to the collaborative efforts of behaviorists, physiologists, ecologists, and engineers, this volume makes a quantum step toward understanding the underwater behavior of air-breathing vertebrates." -James A. Estes, Fish and Wildlife Service/University of California, Santa Cruz The contributors to this volume have accomplished a breakthrough in our ability to collect data on ocean-dwelling mammals. In the first large-scale comparison of fur seals, or of any group of marine mammals, they have employed quantitative methods and a special instrument called a Time-Depth-Recorder to study the strategies used by females in six species of eared seals to rear and wean their young in different environments. They present detailed information on the aquatic life of seals, particularly of subpolar and tropical eared seals, and point to future measurements of physiology and ecology that could result from improved instrumentation. The book contains an introduction and a chapter on methodology by the editors, Roger Gentry and Gerald Kooyman. Other contributors are Daniel P. Costa, John P. Croxall, Jeremy H.M. David, Randall W. Davis, D. William Doidge, Michael E. Goebel, John R. Holt, Patricia Majluf, T. Seamus McCann, Robert W. Rand, M. Sanchez-Grinan, and Fritz Trillmich. Roger L. Gentry is a wildlife biologist at the National Marine Fisheries Service, National Marine Mammal Laboratory, in Seattle, Washington. Gerald L. Kooyman is a research physiologist at the Physiological Research Laboratory, Scripps Institution of Oceanography, in La Jolla, California.