Olympic Coast National Marine Sanctuary represents one of North America's most productive marine ecosystems and spectacular undeveloped shorelines. Marine wildlife thrives here. Twenty nine species of marine mammals and scores of seabird species spend parts of their lives here; gray whales visit as part of the longest mammal migration on earth and albatross gather food here to return to nestlings on mid-Pacific islands and atolls. Sea otters munch on macro-invertebrates such as urchins, which in turn graze on majestic kelp forests. Fishes occupy myriad niches from the deepest ocean canyons to the shallowest tide pools. Influenced by geology, ocean currents and other global processes, the Olympic Coast's temperate location and physical environment supports critical habitats and unique communities of organisms, including one of the most diverse seaweed communities in the world. This Encyclopedia is meant to provide natural history information, video clips, still images, and additional resources to find more information about the marine life found within the sanctuary. We hope you find this to be a valuable resource.