This book describes the environment and behaviour patterns of the Weddell seal. Based on his numerous expeditions to the Antarctic, Dr Kooyman has analysed the seal's diving physiology and acoustical biology. The seal's remarkable adaptation to its environment is evidenced in its ability to dive to 600 meters and return without ill effect and to remain submerged for more than one hour, even though it is an air-breathing animal. The seal holds a unique niche in the world's ecology; it occupies the most southern latitude of any mammal on a permanent basis. The study of this seal has provided important insights into methods of animal navigation, respiration and metabolism. Dr Kooyman is well known as an authority on the Weddell seal. During his fifteen trips to the Antarctic since 1961, he has studied the seal extensively. This book should appeal to marine biologists, animal physiologists and to all those with a serious interest in natural history and life in the Antarctic.