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Diving, Protecting and Enjoying the Monterey Bay National Marine Sanctuary

Monterey Bay National Marine Sanctuary

Monterey Bay National Marine Sanctuary - Overview

Sanctuary Map

   The Monterey Bay National Marine Sanctuary encompasses over 5,000 square miles, stretching along the Central California coast from Marin County near San Francisco southward to Cambria in San Luis Obispo county. The Sanctuary protects many habitats, ranging from sand flats along the shoreline to the nation's most expansive kelp forests and one of its largest underwater canyons. Surrounding wetlands provide nursery grounds for juvenile aquatic life, help protect against flooding and improve water quality by filtering out pollutants.

Nutrient-rich currents nourish the area, supporting a productive and diverse marine ecosytem where countless species, many of them threatened or endangered, make their homes.

Silhouetted diver

Help Protect Your Marine Sanctuary

   In 1992, the Monterey Bay and surrounding Central California coastal waters became the largest National Marine Sanctuary. The purpose of a marine sanctuary is to protect ecological and historical resources. The Monterey Bay National Marine Sanctuary spans over 5,300 square miles from San Francisco to San Simeon. Sanctuary boundaries extend from the high tide line to 50 miles offshore.

   Reaching 100,000 feet in depth, the Monterey Bay canyon is the most notable geographic feature in the Sanctuary. The geology of the canyon and the rest of the Sanctuary is complex. This diverse geology provides for a wide variety of habitats. Warm and cold waters, mixed by wind and ocean currents, bring nourishment to plants and animals in many habitats. Diving in the Sanctuary is superb; this area has exceptional natural beauty and abundant marine resources. Enjoy your visit!

Marine Mammals and You


   You are most likely to see seals, sea lions, or sea otters on your dives in the Sanctuary. Curious animals may even swim up to you. Although it may be tempting to approach for a closer look, remember that these animals are wild.

   For your sake and theirs, observe marine mammals from a distance. If they start to look in your direction and fidget, you are much too close and should back quietly away. The National Oceanic and Atmospheric Administration recommends you stay 50 to 100 yards away from all animals, whether in the water or on shore.

   In addition, please do not feed marine mammals. It could be dangerous to you and is not healthy for the animals.

If You See A Pup On The Beach

   A seal or sea lion pup found alone on the beach is generally not an abandoned animal. Usually, the mother has left it temporarily while she is feeding. Please leave the pup alone. Any attempt to move it may cause you or the pup to get hurt, or cause the mother to abandon the pup.

   If you see a seal or sea lion you think needs care, leave it alone and call the Marine Mammal Center Hotline at (408) 633-6298. If you see a sea otter pup you think is abandoned, leave it alone and call the Monterey Bay Aquarium's Sea Otter Rescue and Care Program at (408) 648-4829. They will determine the best course of action for the animal.

Fishy Denizens

   The Monterey Bay National Marine Sanctuary contains a wide variety of habitats. Diving is superb in one of the more unique habitats, the kelp forest.

   You can recognize the leopard shark by the spots on its back. Like most sharks in the Sanctuary, it is not considered dangerous to humans. It eats small fish and shellfish.

   Kelp provides food and shelter for small and large fishes such as the seņorita and kelp bass. These fishes eat small invertebrates living in the water and on kelp.

   Blue rockfish are a common schooling fish of the kelp forest. You might see them nestled among stalks of kelp or feeding on small swimming animals.


   Look for cabezon and lingcod on the rocky bottom of the kelp forest. Cabezon are brownish or reddish and are noted for their large head and 'stalks' rising just behind their eyes. They eat crab, shrimp, and molluscs. The sleeker lingcod are spotted, gray to green in color, have a longer head and jaw, and eat other fish.

Dive Carefully in Fragile Habitats

   Look closely at any rocky reef, patch of sandy sea floor, or kelp forest and you will be amazed at the myriad of life. As a diver, it is important to remember that poor diving practices can destroy fragile habitats or injure animals. Near the bottom, a misplaced foot can spell disaster for a plant or animal. Many of the animals that you might disturb cannot find their way back to their homes and may die. Be sure to maintain proper buoyancy when diving to avoid harming the habitats you are exploring.

Resist Collecting Undersea Treasures

   The Sanctuary is a treasure trove of beautiful objects, but it is important to resist the urge to collect souvenirs during your dive. A beautiful shell might one day be a home for a hermit crab or a safe refuge for a young fish. Even old wrecks and other human artifacts are protected by the Sanctuary. Regulations prevent the removal of historical resources. Photos and great memories are your best souvenirs.

Help Keep Sanctuary Waters Clean

   We are fortunate that the Sanctuary has some of the cleanest coastal waters in the world. You can help keep the Sanctuary a beautiful place by preventing oil, gas, and other chemicals from getting into the water. Stow your trash for disposal in port, and pick up any plastic you see floating in the water. Birds, fish, mammals, and sea turtles can get entangled in plastic items or mistake them for food. Please help remove plastics from the ocean!

Protect Nesting Fish

   In the winter months, male lingcod and cabezon guard nests of the female's eggs. At these times, males are very territorial and will not leave the nest. This behavior makes them easy targets for spearfishers. Please try to be more conservation-minded, and take fewer lingcod and cabezon in the winter when they are guarding their nests.

Become Involved

   Protecting the Sanctuary is a big job. Consider joining a local environmental group. We all need to protect one of the world's finest ecosystems. Keep a watchful eye for destructive disturbances or activities. Please report them to the NOAA Office of Enforcement (408) 647-4220.

More Information on Diving

   For more information on diving, contact local dive shops. For fishing licenses contact a sporting goods store or the California Department of Fish and Game, (707) 944-5500, (408) 649-2870. For more information on the Monterey Bay National Marine Sanctuary and regulations, please contact the National Oceanic and Atmospheric Administration: (408) 647-4201.

All information about MBNMS provided by US Department of Commerce.

View the Wilds of a Sanctuary


  You can find picture-postcard scenes every day in the Monterey Bay National Marine Sanctuary. On a rocky shore, waves break over mussel beds. On a sandy beach, hungry sanderlings chase the surf. In a kelp forest, a mother sea otter and pup rest. Through blue-green water, a sardine school glides. In an underwater canyon, a cat shark slips through blackness.

   The Monterey Bay National Marine Sanctuary is a haven for sea otters, seals, shorebirds, squid, sardines and thousands of other species, including many that are threatened or endangered. But most important, the sanctuary boundaries include nutrient-rich currents that nourish the area and make possible the rich, diverse marine life.

   Within the sanctuary, scientists study deep-sea life, sightseers spy rugged rocky shores, divers explore majestic kelp forests and fishermen harvest the bounty. Because this is a sanctuary, educators, researchers, resource managers and resource users safeguard pristine waters and abundant marine life. What you see today will enrich and delight future generations.

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