Along the western coast of the North American continent flows an ocean current that contains some of the richest waters in the world when it comes to the study and observation of marine mammals (fig. 1). Worldwide, some 130 different species of marine mammals exist, and more than a third of these are residents or migrants to this rich region. From Killer Whales that dwell around Vancouver Island, Canada, and Gray Whales that give birth in the lagoons of Baja California to Sea Otters that nestle in nearshore kelp beds and elephant seals that plumb the depths of the Pacific...

“Cetacean” is derived both from the Greekketos, for “sea monster” or “huge fish,” and the Latincetus, for “large sea animal.” The order includes hairless, fishlike mammals that live entirely in water (fig. 40). They shed their fur and evolved an impermeable skin and thick blubber. They also shed their land-based hind limbs to assume a fishlike shape with flukes as tails. The tail is the primary means of propulsion through the water.

Although they are not carnivores per se, all cetaceans eat other animals, ingesting prey varying from crustaceans to other marine mammals. A primary difference between kinds...

Living marine mammals under Carnivora fall within five families. Pinnipeds are grouped in three separate families under the suborder Pinnipedia, otters in the Mustelidae family, and polar bears in the Ursidae family. Polar bears are classed as marine mammals because they have evolved special features to live in the ocean, but they range far north of the California Current (CC).

Pinnipeds, seals and sea lions, have “winged feet,” from the Latin for “feather” (pinna) and “foot” (ped) (fig. 90). They lead a dual existence: like whales for their life in the sea, and like wolves for their life on land....