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middle at Sindkhatudi in Kala- kot, Kashmir'. Stable isotope data indi­ cate that Indohyus spent most of its time in water coming to land only to feed on vegetation or invertebrates found on the shore. Many palaeontological records support the theory of cetaceans originat­ ing from an Indohyus-like ancestor that later evolved to a more aquatic lifestyle due to change in diet. Over time, modern- day cetaceans have evolved from their ancestors with many adaptations special­ ized to suit their aquatic lifestyle'. Out of the 130 species of marine re­ ported from all over the world, stranding and sighting records show that the Indian seas are a habitat of 25 species of cetace­ ans and one species of sirenian, and this book provides information about the 25 species of cetaceans. Five species be­ long to the sub-order Mysticeti (Baleen MARINE or toothless ) and the rest 20 be­ SPECIES 0£-JNPI A long to sub-order Odontoceti (toothed whales). Chapters 2-4 deal with the methodo­ logy used to conduct the survey, infor­ mation on the cetacean species and suggestions on designing and conducting marine mammal surveys. Chapter 2 deals with the survey methodology. The survey was done in the exclusive economic zones (EEZs) and the contiguous seas within the Indian territory. A major part of the 7500 km of the country’s coastline falls under the 2,305,143 sq. km of the Marine Mammal Species of . EEZ. This survey covered northeastern E. Vivekanandan and R. Jeyabaskaran. Arabian Sea, southeastern Arabian Sea, Central Marine F isheries Research Insti­ northern Bay of Bengal, southern Bay of tute (ICAR), Kochi. 2012. 228 pp. Price: Bengal, Andaman Sea and the southern Rs 750.______Sri Lanka Sea. The data were collected by conducting single-observer surveys This book is a source of collective infor­ on an oceanographic research vessel mation on the marine mammal species However, the surveys were not system­ found in the Indian seas. It is the out­ atically planned due to logistic con­ come of a nine-year study (2003-2011) straints. An observer was positioned at a funded by the Centre for Marine Living height of 17 m above sea level and the Resources and Ecology, Ministry of area was scanned in a 180° arc with the Earth Sciences, Government of India, naked eye and interspersed with scans and the Central Marine Fisheries Insti­ using binoculars for an average of tute, Kochi, Kerala. 8 h/day. The cetaceans that were spotted The book starts with a brief introduc­ were identified to lowest taxonomic level tion on the order being the most possible and were compared with the diverse, having evolved from land- photographs and morphological identifi­ dwelling ancestors around 50-60 million cations available. Out o f a total of 1068 years ago. More information regarding days on which surveys were conducted, the could have cetaceans were spotted on 430 days. A been provided by the authors. Cetaceans record of 626 sightings comprising 8674 originated about 50 million years ago in individuals was made with 65% of the South Asia. of an ancestor of the sightings in oceanic waters (>200 m cetaceans, Indohyus were discovered depth) and the remaining 35% on the from a 50 m thick bone bed from the continental shelf (<200 m depth). High- est number of sightings (31%) was be­ information is divided. Information pro­ non-availability of a survey vessel enti­ tween 1500 and 1800 h. The survey team vided in the book on Pygmy sperm rely dedicated to the study and sufficient recorded 18 cetacean species (six species (Kogia breviceps and K. sima). Melon­ financial backing. This book presents of whales and 12 species of ). headed whale (Peponocephala electro), consolidated information of the species Out of the total 626 sightings, 57.7% was Cuvier’s beaked whale (Ziphus caviro- and its ecology. Records of sightings, identified to either generic or species stris). Pygmy killer whale (Feresa attenu­ stranding and incidental catches have level. However, the rest of the 42.3% ate) and Rough toothed (Steno been complied in the book. Information could not be identified. The team sighted bredanensis) are based on stranding re­ on a species found in Indian waters from and recorded during the surveys whale cords and previous sighting records as other parts of its distributional range has and dolphin pods varying from 1 to 10 these species were not sighted during the also been provided. In conclusion, the individuals and 1 to 100 individuals re­ survey. book is a much needed pictorial guide for spectively. They found sightings to be The authors mention four cetaceans, marine mammal identification in India highest during January and lowest during the Irrawady dolphin (Orcaella brevi- and will be helpful for those working in August. This variation might be because rostris), Gangetic dolphin (Platanista marine ecology. We hope better financial of bad visibility due to choppy sea condi­ gangetica gangetica). Sperm whale backing and support will help the authors tions during the monsoon season. Indo- (Physeter macrocephalus) and Dugong improve the quality and contents of the Pacific Bottle Nose dolphin (Tursiops (Dudong dugong) to be under Schedule 1 book in its future editions. aduncus). Spinner dolphin (Stenella of the Wildlife (Protection) Act (WPA) longirostris) and Long-beaked Common of 1972. Though Sperm whale does not dolphin (Delphinus capensis) were the come under Schedule 1, it is included in 1. Thewissen, J. G. M., Cooper, L. N., Clementz, M. T., Bajpai, S. and Tiwari, B. species that were commonly sighted by Schedule 2 of the WPA. However, the N., Nature, 2007, 450, 1190-1194. the team. The authors also tried to iden­ Little Indian porpoise (Neophocaena tify the habitat preference of the cetace­ phocaenoides) is included in Schedule 1 ans by measuring distance from the of the WPA. The authors have over­ R. K. SiNHA shore, depth, temperature and salinity of looked this mistake in the book. the sea water. Chinese white dolphin In chapter 4 titled ‘Future directions’, Environmental Biology Laboratory, {Sousa chinensis) was sighted nearest to the authors provide many suggestions on Department o f Zoology, the shore, -100 km from the shore, conducting research and survey on marine Patna University, whereas Long-beaked Common dolphin. mammals. They support and highlight Patna 800 005, India Spinner dolphin and Indo-Pacific Bottle the need for the establishment of Marine e-mail: [email protected] Nose dolphin were sighted at -199, -499 Mammal Stranding Network and Marine and -599 km respectively, from the Mammal Conservation Network which shore. Most of the cetacean sightings will be helpful in documenting cetacean were in the 26°-32°C temperature range stranding reports and also help in prepar­ where salinity ranged between 26 and 36 ing an action plan for conservation of parts per thousand. The authors, how­ marine mammals in India. They also ever, are not sure of these data, as it is highlight the importance of conserving known that the temperature of the sea sea grass beds, the much needed amend­ water does not have much effect on the ment to the Marine Fishing Regulation use of an area by cetaceans especially in Act, and the need to educate and spread tropical area. awareness among fishermen on the basic Chapter 3 provides information on functioning of marine ecosystems and each of the 25 species. The taxonomic the need to conserve them. The inclusion status, common name, identification of a glossary section in the book pro­ characters, distribution, abundance, habi­ vides definitions for the technical terms tat, behaviour, food, exploitation, and used throughout, making comprehension threats and conservation status are the easy. categories under which the available Very few studies or surveys on marine mammals have been conducted in India until now. Most of the information avail­ able is based on incidental catches and on individuals that were stranded or beach cast. This study has contributed significant knowledge on the country’s marine mammal diversity and the effort of the authors is commendable as identi­ fication of marine mammals in open sea is a difficult task. Good identification guides and trained observers are essential Acrobatic leap of Stenella longrostris sighted off Dwaraka, Gujarat on to conduct such surveys. This was one of 23. 03. 2009. the handicaps in the survey in addition to