The marine mammal commonly seen off the Pacific Coast is the sea lion.

Sea lions, particularly the California sea lion, are frequently spotted along the Pacific Coast, especially in California, where they thrive in the coastal environment. These agile and social mammals are known for their playful behavior and distinctive barks. They have external ear flaps and long front flippers that help them navigate both land and water efficiently. Sea lions often gather in large groups on rocky shores and piers, creating lively colonies. They primarily feed on fish and squid, playing a vital role in the marine ecosystem. Their presence attracts wildlife watchers and contributes to the region's ecotourism, enhancing local economies.