Marine Mammals of the World: A Comprehensive Guide to Their Identification
Format: PDF / Kindle (mobi) / ePub
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.
females are up to 12 m and adult males are up to 18.3 m in length. Weights of up to 57,000 kg have been recorded. Sperm whales are the most sexually dimorphic of all cetacean species, with males weighing nearly three times as much as females. Adult female--Relatively large size, pale dorsal fin callus usually present (although sometimes difficult to see), dorsal fin more anterior than in adult males. Adult male--Large body size (up to about 50% larger than females), often with extensive
black mottling still remaining on the upper surfaces (especially the top and front of the head and along the dorsal ridge) and appendages (often as dark borders on the flukes and flippers). The narwhal's most remarkable feature, however, is its teeth. There are only two teeth, both in the upper jaw. In females, these almost always remain embedded in the upper jaw bones, but in males the left tooth nor- A group of traveling narwhals; the lead animal is a young male with a partially grown tusk.
Hudson Strait, and 300 in Scoresby Sound). IUCN status References Born et al. 1994; Heide-Jorgensen 2002; Heide-Jorgensen et al. 2003; Reeves and St. Aubin 2001; Reeves and Tracey 1980. Narwhals are perhaps the most northerly of all cetaceans and are rarely found far from Arctic ice. PHOTO:K, LAIDRE Narwhals are social animals that live among the Arctic ice--as such, they are likely to be affected by global warming more than most other species of marine mammals. PHOTO:J, K, B FORD 88 Data
jaw, in combination with their white beaks and closely-paired scratches, should allow them to be distinguished from other species of Mesoplodon that are sympatric, if the head is seen quite well. Of the species that share the range of Hector's beaked whale, Gray's beaked whale can be similar in appearance. For adult males, note the presence (Hector's) or absence (Gray's) of paired scratches, and placement of the tusks at the tip (Hector's) or middle (Gray's) of the lower jaw. Distribution
PHOTO:NATIONAlSCIENCEMUSEUM, COURTESYOFT,YAMADA of t h e W o r l d Sea. Based on a number of fetuses that have recently been examined, calving in the North Pacific appears to occur mainly from spring to early autumn, although the season may be protracted. Sexual maturity apparently occurs by about 4.5 m. Longevity is known to be at least 36 years, based on the aging of 7 specimens. Feeding and prey Stejneger's beaked whales are known to feed primarily on squids of the families Gonatidae and