Life in Monterey Bay

More than 30 species of marine mammals live in or pass through Monterey Bay. Mammals that live in the ocean range in size from the furry, five-foot-long sea otter to the enormous blue whale, a hundred feet long. What do these creatures have in common? Like us, they are warm-blooded animals that breathe air, have hair and nurse their young. The marine mammals that live in or pass through Monterey Bay can be divided into three major groups. Each group evolved from different land mammals that moved back to the sea.
		Whales, Dolphins and Porpoises (Cetaceans) The cetaceans descended from cowlike ancestors that returned to ocean life about 65 million years ago. The streamlined, fishlike whale doesn't resemble its ancestor. With one or two nostrils on the top of its head, a whale can easily breathe at the surface without lifting its head. Its tail is incredibly strong, powerful enough to push the whale through the water.

Seals and Sea Lions (Pinnipeds)
The pinnipeds

are graceful and agile swimmers with smooth, tapering bodies and strong flippers, but they retain many ties to the land. Most return to shore, some more gracefully than others, to mate and give birth.

Though they look alike, seals and sea lions spring from two different families and they lead different lives. Traits they share show us how warm-blooded animals can live in the sea: big eyes and sharp hearing for dark water, where sound travels faster than in air; fur and blubber for warmth in the chilling sea; flippers and streamlining for graceful swimming.

Awkward and cumbersome on land, harbor seals maneuver with grace and agility in the water. � Mark Conlin

Otters in rafts often sleep side-by-side—sometimes wrapped up in strands of kelp—so that they don't drift far from each other. � Frank Balthis

Sea Otters

The sea otter

, adapted to living in the ocean over the past four million years, still resembles the weasel, its relative on land. Sea otters live close to shore; they're not as well equipped for the open ocean as the streamlined, deep-diving seals and whales. You can find much more about sea otters in our Sea Otter Exhibit section and Sea Otter Research and Conservation sections.

Inspiring conservation of the oceans