Diving Physiology Of Marine Mammals And Seabirds

An up-to-date synthesis of comparative diving physiology research, illustrating the features of dive performance and its biomedical and ecological relevance.

Suppose you were designing a marine mammal. What would you need to think about to allow it to live in the ocean? How would you keep it warm? What would you design to allow it to dive for very long periods to extreme depths? Where would it find water to drink? How would you minimize the cost of swimming, and how would it find its prey in the deep and dark? These questions and more are examined in detail throughout this book. Marine Mammal Physiology: Requisites for Ocean Living is the first textbook focused on how marine mammals live in the sea from a physiological point of view. It explores the essential aspects of what makes a marine mammal different from terrestrial mammals, beyond just their environment. Unlike many publications and books that cover these species from almost all perspectives, this textbook takes a step back to focus on the physiological and biochemical characteristics that have allowed these mammals as a group to exploit effectively the marine environment that is so hostile to humans. The chapter topics are grouped into major themes: diving and locomotion, nutrition and energetics, reproduction, sensory systems, and environmental interactions. Each chapter is arranged around a common perspective and theme: the big picture challenge and summary and what is known specifically by order. To aid you even further, the authors include a "Toolbox" section in each chapter where they discuss the newest methods for understanding and working on the physiology of marine mammals.

Breath-hold diving marine mammals are able to remain submerged for prolonged periods of time and dive to phenomenal depths while foraging. A number of physiological, biochemical and behavioral traits have been suggested that enable this life style, including the diving response, lung collapse, increased O2 stores, diving induced hypometabolism, and stroke-and-glide behavior to reduce dive metabolic cost. Since the initial studies by Scholander in the 1940‘s, when most of the physiological and biochemical traits were suggested, few have received as much study as the diving response and O2 management. The calculated aerobic dive limit (cADL) was an important concept which allowed calculation of the aerobic dive duration, and was defined as the total O2 stores divided by the rate of O2 consumption (metabolic rate). The total O2 stores have been defined for several species, and studies in both forced and freely diving animals have refined the metabolic cost of diving. Currently there appears to be little consensus about whether marine mammals perform a significant proportion of dives exceeding the cADL or not and there may be large differences between species. The diving response is a conserved physiological trait believed to arise from natural selection. The response includes diving-induced bradycardia, peripheral vasoconstriction, and altered blood flow distribution. While the response results in reduced cardiac work, it is not clear whether this is required to reduce the overall metabolic rate. An alternate hypothesis is that the primary role of the diving bradycardia is to regulate the degree of hypoxia in skeletal muscle so that blood and muscle O2 stores can be used more efficiently. Scholander suggested that the respiratory anatomy of marine mammals resulted in alveolar collapse at shallow depths (lung collapse), thereby limiting gas exchange. This trait would limit uptake of N2 and thereby reduce the risk of inert gas bubble formation and decompression sickness. In his initial treatise, Scholander suggested that alveolar collapse probably made inert gas bubble formation unlikely during a single dive, but that repeated dives could result in significant accumulation that could be risky. Despite this, lung collapse has been quoted as the main adaptation by which marine mammals reduce N2 levels and inert gas bubble formation. It was surprising, therefore, when recent necropsy reports from mass stranded whales indicated DCS like symptoms. More recent studies have shown that live marine mammals appear to experience bubbles under certain circumstances. These results raise some interesting questions. For example, are marine mammals ever at risk of DCS, and if so could N2 accumulation limit dive performance? While an impressive number of studies have provided a theoretical framework that explains the mechanistic basis of the diving response, and O2 management, many questions remain, some widely-accepted ideas actually lack sufficient experimental confirmation, and a variety of marine mammal species, potentially novel models for elucidating new diving adaptations, are understudied. The aim of this Frontiers Topic is to provide a synthesis of the current knowledge about the physiological responses of marine mammals that underlie their varied dive behavior. We also include novel contributions that challenge current ideas and that probe new hypotheses, utilize new experimental approaches, and explore new model species. We show that the field has recently entered a phase of renewed discovery that is not only unraveling more secrets of the natural diving response but will drive new applications to aid human exploration of the ocean depths. We also welcome comparative analyses, especially contributions that compare marine mammals with human divers.

Suppose you were designing a marine mammal. What would they need to live in the ocean? How would you keep them warm? What design features would allow them to dive for very long periods to extreme depths? Do they need water to drink? How would they minimize the cost of swimming, and how would they find their prey in the deep and dark? These questions and more are examined in detail throughout Marine Mammal Physiology, which explores how marine mammals live in the sea from a physiological point of view. This undergraduate textbook considers the essential aspects of what makes a marine mammal different from terrestrial mammals, beyond just their environment. It focuses on the physiological and biochemical traits that have allowed this group of mammals to effectively exploit the marine environment that is so hostile to humans. The content of this book is organised around common student questions, taking the undergraduate's point of view as the starting point. Each chapter provides a set of PowerPoint slides for instructors to use in teaching and students to use as study guides. New "Study Questions" and "Critical Thinking Points" conclude each chapter, which are each motivated by a "Driving Question" such as "How do mammals stay warm in a cold ocean?" or "How do mammals survive the crushing pressures of the deep sea?" Full-colour images and comprehensive, accessible content make this the definitive textbook for marine mammal physiology.

This thorough revision of the classic Encyclopedia of Marine Mammals brings this authoritative book right up-to-date. Articles describe every species in detail, based on the very latest taxonomy, and a host of biological, ecological and sociological aspects relating to marine mammals. The latest information on the biology, ecology, anatomy, behavior and interactions with man is provided by a cast of expert authors – all presented in such detail and clarity to support both marine mammal specialists and the serious naturalist. Fully referenced throughout and with a fresh selection of the best color photographs available, the long-awaited second edition remains at the forefront as the go-to reference on marine mammals. More than 20% NEW MATERIAL includes articles on Climate Change, Pacific White-sided Dolphins, Sociobiology, Habitat Use, Feeding Morphology and more Over 260 articles on the individual species with topics ranging from anatomy and behavior, to conservation, exploitation and the impact of global climate change on marine mammals New color illustrations show every species and document topical articles FROM THE FIRST EDITION “This book is so good...a bargain, full of riches...packed with fascinating up to date information. I recommend it unreservedly it to individuals, students, and researchers, as well as libraries." --Richard M. Laws, MARINE MAMMALS SCIENCE "...establishes a solid and satisfying foundation for current study and future exploration" --Ronald J. Shusterman, SCIENCE

Comprehensive manual for understanding and carrying out marine mammal rescue activities for stranded seals, manatees, dolphins, whales, or sea otters.

The Encyclopedia of Marine Mammals, Third Edition covers the ecology, behavior, conservation, evolution, form and function of whales, dolphins, seals, sea lions, manatees, dugongs, otters and polar bears. This edition provides new content on anthropogenic concerns, latest information on emerging threats such as ocean noise, and impacts of climate change. With authors and editors who are world experts, this new edition is a critical resource for all who are interested in marine mammals, especially upper level undergraduate and graduate students, researchers, and managers, and is a top reference for those in related fields, from oceanographers to environmental scientists. Significant content and topic updates, as well as the addition of new topics in such areas as anthropogenic disturbance Visual maps of the oceans and seas mentioned in contributions, helping to place the geographical features described in the text with clear, consistent species illustrations Written to help users learn new information or brush up on a topic quickly, with the references at the end of each entry to help guide readers into more specialist literature

With coverage on all the marine mammals of the world, authors Jefferson, Webber, and Pitman have created a user-friendly guide to identify marine mammals alive in nature (at sea or on the beach), dead specimens “in hand , and also to identify marine mammals based on features of the skull. This handy guide provides marine biologists and interested lay people with detailed descriptions of diagnostic features, illustrations of external appearance, beautiful photographs, dichotomous keys, and more. Full color illustrations and vivid photographs of every living marine mammal species are incorporated, as well as comprehendible maps showing a range of information. For readers who desire further consultation, authors have included a list of literature references at the end of each species account. For an enhanced understanding of habitation, this guide also includes recognizable geographic forms described separately with colorful paintings and photographs. All of these essential tools provided make Marine Mammals of the World the most detailed and authoritative guide available! * Contains superb photographs of every species of marine mammal for accurate identification * Authors’ collective experience adds up to 80 years, and have seen nearly all of the species and distinctive geographic forms described in the guide * Provides the most detailed and anatomically accurate illustrations currently available * Special emphasis is placed on the identification of species in “problem groups, such as the beaked whales, long-beaked oceanic dolphin, and southern fur seals * Includes a detailed list of sources for more information at the back of the book.