Marine Mammal Ecology and Conservation / 00-Boyd_Prelims page 3 7:41pm OUP CORRECTED PROOF – Finals, 5/7/2010, SPi Marine Mammal Ecology and Conservation A Handbook of Techniques Edited by Ian L. Boyd W. Don Bowen and Sara J. Iverson 1 Marine Mammal Ecology and Conservation / 00-Boyd_Prelims page 4 7:41pm OUP CORRECTED PROOF – Finals, 5/7/2010, SPi 3 Great Clarendon Street, Oxford ox2 6dp Oxford University Press is a department of the University of Oxford. It furthers the University’s objective of excellence in research, scholarship, and education by publishing worldwide in Oxford New York Auckland Cape Town Dar es Salaam Hong Kong Karachi Kuala Lumpur Madrid Melbourne Mexico City Nairobi New Delhi Shanghai Taipei Toronto With offices in Argentina Austria Brazil Chile Czech Republic France Greece Guatemala Hungary Italy Japan Poland Portugal Singapore South Korea Switzerland Thailand Turkey Ukraine Vietnam Oxford is a registered trade mark of Oxford University Press in the UK and in certain other countries Published in the United States by Oxford University Press Inc., New York q Oxford University Press 2010 The moral rights of the authors have been asserted Database right Oxford University Press (maker) First published 2010 All rights reserved. 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ISBN 978–0–19–921657–4 (Pbk.) 13579108642 Marine Mammal Ecology and Conservation / 00-Boyd_Prelims page 2 7:41pm OUP CORRECTED PROOF – Finals, 5/7/2010, SPi Techniques in Ecology and Conservation Series Series Editor: William J. Sutherland Bird Ecology and Conservation: A Handbook of Techniques William J. Sutherland, Ian Newton, and Rhys E. Green Conservation Education and Outreach Techniques Susan K. Jacobson, Mallory D. McDuff, and Martha C. Monroe Forest Ecology and Conservation: A Handbook of Techniques Adrian C. Newton Habitat Management for Conservation: A Handbook of Techniques Malcolm Ausden Conservation and Sustainable Use: A Handbook of Techniques E.J. Milner-Gulland and J. Marcus Rowcliffe Invasive Species Management: A Handbook of Principles and Techniques Mick N. Clout and Peter A. Williams Amphibian Ecology and Conservation: A Handbook of Techniques C. Kenneth Dodd, Jr. Insect Conservation: Approaches and Methods Michael J. Samways, Melodie A. McGeoch, and Tim R. New Marine Mammal Ecology and Conservation: A Handbook of Techniques Ian L. Boyd, W. Don Bowen, and Sara J. Iverson Remote Sensing for Ecology and Conservation: A Handbook of Techniques Ned Horning, Julie A. Robinson, Eleanor J. Sterling, Woody Turner, and Sacha Spector Marine Mammal Ecology and Conservation / 00-Boyd_Prelims page 5 7:41pm OUP CORRECTED PROOF – Finals, 5/7/2010, SPi Preface Arguably, a piece of research is only as good as the methods used to derive and interpret the data. In this respect, studies of the biology of marine mammals are no different from any other research. However, where they do tend to differ is in the particular challenges presented by the aquatic lifestyle, their large body size and, in many cases, the endangered status of marine mammals. The total amount of research on marine mammals has increased rapidly in recent decades. By any metrics—number of researchers, total funding, relevance to policy or commerce, research outputs, quality of research outputs, or the number of meetings or conferences dedicated to marine mammals world-wide—there has been a rapid increase in the volume and sophistication of research being carried out on marine mammals. This has changed the field from a small, slightly cliquey branch of research that sat at the boundaries between physiology, ecology, mammalogy, behavioural biology, and marine biology to one that is making an important contribution to many of these fields and that is now contributing to the develop- ment of ideas in diverse areas of biology. This contribution lies in both the theoretical and empirical spheres of biology. Some 30 years ago, the principal method for studying marine mammals was for researchers to follow in the wake of hunters or become hunters themselves and work with dead tissue samples. Times have changed. Remarkable innovations have led to new ways of investigating the lives of marine mammals. Some of these have relied upon the development of new technology, but many have been driven by genuine ingenuity, invention, and intellectual advances, as represented by examples of novel instruments for obtain- ing measurements or statistical approaches to analysing and interpreting data. Marine mammals present particular challenges to ecologists and conservation biologists. They are often difficult to observe, at least during certain critical parts of their life cycle; they occupy a vast environment both in terms of the geographical range of species and their use of the water column. They present difficult conser- vation challenges both because there may be perceived conflicts between people and marine mammals and because some species are close to extinction. Marine mammals also command a high level of public attention (they can be truly described as ‘charismatic species’)reflected in specific legislation for their protec- tion and management in many countries. Although there are numerous books about marine mammals, there has been only one previous attempt to produce a book that summarized techniques in an aspect of marine mammalogy (Laws 1993). Consequently, we approached the task of producing this book with the objective of summarizing the methodological Marine Mammal Ecology and Conservation / 00-Boyd_Prelims page 6 7:41pm OUP CORRECTED PROOF – Finals, 5/7/2010, SPi vi j Preface approaches to studying marine mammals in a single, accessible, authoritative volume. Although it is in the nature of scientific writing to provide detailed descriptions of methods, there are several reasons why we considered that it would be useful to produce a higher level description in a single volume. First, we are aware of the new generations of marine mammalogists that will be entering training. Their experience of the methodological pallet available to them in their research careers needs to be broader and more integrative than anything they can obtain from the condensed descriptions of methods found within research papers. Second, we wish to encourage experienced researchers ‘to think outside the box’. For many, the methods they use will represent the constraints on what they can study and it is possible that we might be able to encourage innovation by making connections across different approaches. Third, we also see a need to standardize methods once they have become accepted and established, because through standardization one can encourage cross-compatibility of studies (although we also recognize that standardization is tensioned against innovation in many ways). Finally, we want to encourage researchers to think first and then act. This is central to the increasingly important ethical approach to research as discussed in Chapter 1. Research these days is highly regulated, but it is essential for researchers themselves to regulate their activities because, if they fail to do so, other less qualified individuals will do so. The consequences of this will be bad for humanity and for marine mammals. This is why we have opened the book with a chapter on ethics and the reader will find that ethical considerations are an almost continuous thread that is weaved through the fabric of the book. They come to the fore in particular when capturing and handling marine mammals, a subject that is dealt with in Chapter 2. Methods can change, and in some areas of marine mammal biology they are evolving rapidly—tracking technology (Chapter 10), diet estimation (Chapter 9), modelling (Chapters 3 and 4), and population genetics (Chapter 14) to name but four. Application of new technologies and imaginative new approaches are allowing rapid headway in areas previously well beyond the scope of most science. The rapidity of change is a problem for a book of this type because it can soon become outdated. The intention, however, has not been to produce a manual. Instead, we have attempted to produce an overview that will have a long half-life by pointing out generic methods and illustrating their strengths and weaknesses. Our intent to make the book authoritative could rightly have included most active marine mammal researchers as contributors, but this was clearly impossible. Nevertheless, a total of 46 people have contributed their knowledge and expertise to writing this book and we are grateful to all for their contributions. We are also grateful to the numerous individuals who provided reviews of chapters after they had been drafted. The chapter subjects are intended to represent the main areas of marine mammal biology, but doubtless