The 2008 IUCN (International Union for Conservation of Nature) review of thestatus of the world’s mammals identified marine mammals (pinnipeds, cetaceans,sirenians, and the polar bear, Ursus maritimus)aas disproportionally threatened anddata poor compared to their terrestrial counterparts, and their status was noted asa particular concern (IUCN 2008, Mace et al. 2008, Schipper et al. 2008). Thethreats faced by marine mammals were identified as being different, with accidentalmortality and pollution being dominant threats that superseded habitat loss, whichwas identified as the principal concern for land mammals. It was suggested thatharvesting remained a major threat for half of the marine mammal species in theworld. Threat levels were highest for marine mammals living in the North Atlantic,North Pacific, and Southeast Asia. Although these generalities are of course correctfor all marine mammals as a group, it must be recognized that the large numberof species of cetaceans, compared to other marine mammal groups (85 cetaceans vs.the polar bear, 4 sirenians, and 36 pinniped species [including two species newlyclassified as being officially extinct]), biases the conclusions in the assessment formarine mammals to such a degree that a separate summary for the pinnipeds of theworld is warranted.
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