where are these mammals mostly found?
North Atlantic, the North Pacific and the Southern Ocean
Pinniped
Living pinnipeds mainly inhabit polar and subpolar regions, particularly the North Atlantic, the North Pacific and the Southern Ocean. 
what class of vertebrates do seals belong to Pinnipeds what are pinnipeds? Diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. what is the diet of the the last kind of mammal you mentioned? All cetaceans are carnivorous and predatory what kind of threat do these mammals face? Due to the difficulty to survey populations, 38% of marine mammals are data deficient apart from the seal can you name some other animals that full under this type of mammals? Whales, manatees, sea otters and polar bears how do pinniped move from one place to another? They have two pairs of flippers; the fore-flippers and hind-flippers, and smooth networks of muscle bundles in their skin that may increase laminar flow and make it easier for them to slip through water do they sleep? Yes, sleep in water with half of their brain awake
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Pinniped [SEP] Distribution and habitat
Living pinnipeds mainly inhabit polar and subpolar regions, particularly the North Atlantic, the North Pacific and the Southern Ocean. They are entirely absent from Indomalayan waters. Monk seals and some otariids live in tropical and subtropical waters. Seals usually require cool, nutrient-rich waters with temperatures lower than . Even those that live in warm or tropical climates live in areas that become cold and nutrient rich due to current patterns. Only monk seals live in waters that are not typically cool or rich in nutrients. The Caspian seal and Baikal seal are found in large landlocked bodies of water (the Caspian Sea and Lake Baikal respectively).