Sirenian Conservation: Issues and Strategies in Developing Countries

Foreword

Foreword ing wild sirenians and their habitats to enable researchers to provide managers with robust scientific advice. Most of the methods chapters have been co-authored by researchers from more than one country. Although most methods will need to be customized for local application , the wide geographic base of the authorship increases their applicability. Sirenian conservation is not just an issue of biology. All four species are of considerable cultural value to Indigenous and non-Indigenous peoples throughout their ranges, and sirenian conservation is an issue of conserving cultural as well as biological diversity. The extinction of sirenians will result in the local loss of cultural knowledge. Importantly, some of this knowledge is documented in this book. The pressures on dugongs and manatees are almost certain to increase in all of their approximately 90 range states, especially those where food security is likely to be an issue. The world’s human population is projected to grow from 6.8 billion in 2010 to 8.9 billion in 2050, to peak at 9.22 billion in 2075, 35% higher than in 2010. Much of the demographic change up to 2050 will take place in the less developed regions, which will account for 99% of the expected increment to world population in this period. Thus human population increase is projected to be extremely rapid in most of the countries in the range of dugongs and manatees, with increasing food insecurity. In addition, climate change is projected to increase pressure on the world’s fisheries. Many of the countries where the impacts of climate change on fisheries are projected to have the greatest national economic impacts are in the ranges of dugongs and manatees . These projected changes in human population and climate are significant to the future of manatees and dugongs because the population growth rate of all sirenians is highly sensitive to changes in adult survival rate. Most local populations of sirenians cannot withstand the human-induced mortality of even a few animals per year. The future of manatees and dugongs looks bleak When I started studying dugongs in the early 1970s, much sirenian research was limited to the study of the natural history of animals that were dead or in captivity and in the United States or Australia. There are obvious limitations to each of the dimensions of this approach, and this book is testament to the modern, global, crossdisciplinary approaches used to study and inform the conservation management of wild sirenians. The sirenians, the dugong (family Dugongidae) and the three species of manatee (family Trichechidae), are of very high biodiversity value as the world’s only herbivorous mammals that are exclusively aquatic. They have all been included on the IUCN Red List of Threatened Species for decades. The other recent sirenian, the Steller ’s sea cow, is extinct, exterminated by humans less than 30 years after its rediscovery in the eighteenth century. The extinction of Steller’s sea cow is a stark reminder of both the capacity of a species with a once vast range to become extinct and the vulnerability of relatively small isolated populations of sirenians to human impacts, particularly direct mortality. The range of sirenians spans about 90 subtropical and tropical countries on five continents. Almost all these countries are classified as less developed. The book’s editors are based in four countries from the range of three of the four extant sirenians. Eighty sirenian researchers, who are citizens of or have been based in 22 countries, have contributed to this book; more than 50 of these researchers have been or are based outside the United States and Australia. Of the 28 chapters, more than half have been co-authored by researchers from more than one country; this number is higher if the authorship of the text boxes is considered. The editors of this book, particularly Ellen Hines, are to be commended for coordinating such a large global cast of authors. Although the study of dead and captive animals has provided important insights into sirenian biology, modern benign methods are much more powerful. Section II of this book describes a range of techniques for study- throughout most of their ranges in developing countries, unless the issues of food security and alternative livelihoods are addressed. In contrast to the situation that exists for many species , however, enough is known about threats to sirenian populations to take effective steps toward their conservation , if the will exists to do so. This book will assist scientists and managers with responsibilities for...