Cordell Bank National Marine Sanctuary celebrates 30 years of ocean protection

By Larisa Bennett

May 2019

Twenty-two miles offshore of the northern California coastline is a patch of ocean that looks ordinary to the uninformed eye. But beneath the surface of the deep blue Pacific, a towering undersea block of granite crowded with marine life rises up from the gloom of the depths. Cordell Bank hosts throngs of fish, invertebrates, and marine mammals along its four-and-a-half by nine-and-a-half-mile granite outcrop. The bank sits at the edge of the continental shelf and rises abruptly out of the soft seafloor sediments to within 115 feet of the ocean surface.

a rockfish swimming above a rocky reef
The underwater world found along the rise of Cordell Bank hosts a varied array of invertebrates and fish. Photo: NOAA

For 30 years this month, Cordell Bank and the highly productive expanse of seawater surrounding it have been protected by Cordell Bank National Marine Sanctuary. Dr. Sarah Hameed, director of the Cordell Marine Sanctuary Foundation, explains that the bank is “filled with colorful corals, sponges, and rockfishes. Migratory birds, mammals, turtles, and sharks visit from far and wide to feast in the productive waters that surround the bank. It’s a special place for marine biodiversity and a critical place to safeguard.”

At its beginning, the sanctuary was charged with protecting 529 square miles of ocean, including the rocky bank. In 2015, the sanctuary more than doubled in size to protect 1,286 square miles – an area about the size of Rhode Island. The expanded sanctuary encompasses the well-known Bodega Canyon and its abundance of sea life. Sanctuary superintendent Dan Howard says, “When you stop and look back 30 years, it is amazing how much work we have done characterizing and better understanding Cordell Bank National Marine Sanctuary.”

fishes swimming around cordell bank
Cordell Bank provides an oasis for invertebrates, rockfish, and more. Photo: Clinton Bauder/BAUE

Little was understood about the Cordell Bank ecosystem for many years because of the difficulty of diving in the area. Offshore currents and deep pinnacles mean that the bank is out of reach for all but the most experienced divers. Sanctuary staff have worked tirelessly to remedy this knowledge gap.

Due to its offshore location and depth, Cordell Bank went undiscovered by humans until the late 1800s when George Davidson of the U.S. Coast Survey stumbled upon it during a survey of the northern California coast. The bank was named after surveyor Edward Cordell after he more thoroughly mapped the area in 1869. However, the person who has done the most to put Cordell Bank on the map is American scientist Dr. Robert Schmeider, who began his quest to dive on the bank and document the local marine life in 1977. Thanks to his efforts to protect this precious ecosystem, Cordell Bank National Marine Sanctuary was established on May 24, 1989.

Since then, Cordell Bank National Marine Sanctuary has accomplished much in its 30-year history in the realms of education and outreach, management, science and monitoring, and support for sustainable commercial fisheries. From educating teachers on ocean topics such as marine debris or climate change, to employing underwater remotely operated vehicles (ROVs) to gather footage and data about the ecology of Cordell Bank, the sanctuary has worked hard to understand and maintain a healthy ocean community.

During an ROV expedition to Bodega Canyon in 2017 on the E/V Nautilus, researchers found marine life like this octopus. Photo: OET/NOAA

The sanctuary and its partners have worked diligently to protect the animals and ecosystems of Cordell Bank and its surrounding waters. Due to sanctuary regulations, this part of the ocean remains largely protected. The sanctuary has also been key to maintaining complex food webs, working with the Pacific Fisheries Management Council to prohibit the harvest of krill in national marine sanctuaries along the West Coast. Booming populations of krill are the backbone of many ocean ecosystems because they are a vital prey source of many larger species such as seals, whales, fish, and seabirds.

Cordell Bank National Marine Sanctuary has also been a friend to local commercial fishermen. It has advocated for allowing exempted fishing permits for local, small-scale fishermen to utilize hook and line equipment to harvest fish species with healthy populations within national marine sanctuaries. In this way, the sanctuary promotes a strong blue economy while also protecting the species that need support.

whale tail
Whales come to feed in Cordell Bank National Marine Sanctuary because of the tremendous amount of krill in the area. Photo: NOAA

Over the sanctuary’s 30 years, the conservation science program at Cordell Bank National Marine Sanctuary has focused on understanding the ecosystems of the sanctuary and monitoring the conditions of its habitats and wildlife. Technical divers and remotely operated vehicles have explored Cordell Bank, Bodega Canyon, and the surrounding areas to study sanctuary geology, flora, and fauna as well as to create better physical maps of sanctuary areas. Researchers have also mapped the area’s soundscape to better understand the ways human-made noise impacts the sounds animals use for communication and foraging. The sanctuary monitors for low-oxygen conditions and other oceanographic conditions that can harm wildlife, as well. Findings indicate low oxygen water is associated with strong upwelling but water quickly returns to “normal” when upwelling subsides. Sanctuary findings have not only described amazing new species, but have also supported efforts in the designation of no bottom trawl areas, contributed to measures to reduce ship strikes of endangered whales, and linked surface conditions to the health of deep-sea habitats. “All this helps us to do a better job managing these resources,” says Howard.

computer monitors showing readouts from an rov dive
Scientists and sanctuary staff use underwater ROVs to study and monitor Cordell Bank National Marine Sanctuary. Photo: NOAA

The sanctuary can’t do all this alone: it relies on support from and collaboration with a variety of partners. For over 15 years, the sanctuary has worked with Point Blue Conservation Science, a California nonprofit focused on conservation. To Dr. Jaime Jahncke, the California Current director for Point Blue, “The protections provided by the sanctuary are crucial for ensuring that the ocean’s fragile ecosystem is preserved in important areas like Cordell Bank.” He adds, “The monitoring work we’ve done over the years has shown that these protections really do make a difference for the health of our ocean.”

Sanctuary staff and partners also work diligently to share the remote sanctuary with the world. Cordell Gallery in the Oakland Museum of California houses a sanctuary exhibit that enables thousands of museum goers to vicariously experience Cordell Bank’s unique submarine wonders every year. There are also Cordell Bank exhibits at Point Reyes National Seashore with literally millions of annual visitors and a traveling photo exhibit of the sanctuary has been to over 20 locations and reached over 10,000 viewers.

people in a visitor center
Visitors to the ocean Exploration Center at Point Reyes National Seashore’s Historic Lighthouse Visitor Center can get to know the offshore Cordell Bank National Marine Sanctuary. Photo: Tyler Chartier

In a collaboration with Papahānaumokuākea Marine National Monument and the marine ecology non-profit Oikonos Ecosystem Knowledge, the sanctuary has also created the Winged Ambassadors curriculum to bring the sanctuary, and its key species, to students. This curriculum focuses on the albatrosses that feed in Cordell Bank National Marine Sanctuary and breed in Papahānaumokuākea Marine National Monument. As migratory birds, albatrosses link different marine protected areas together and also provide an early indicator of ocean degradation. They are the canaries in the coal mine of the ocean. The Winged Ambassadors program teaches students how to scientifically track these ocean-going birds as well as engages them on issues such as plastic ingestion. Winged Ambassadors has been downloaded and used in over 20 countries.

albatross flying over the ocean
Cordell Bank National Marine Sanctuary’s highly productive waters provide feeding grounds for a variety of birds, including albatrosses. Photo: NOAA

Marine protected areas like Cordell Bank National Marine Sanctuary help protect critical and unique ocean environments. The sanctuary has had a stellar 30 years protecting its priceless treasures – may it be a guardian of the great deep for many more to come.

Larisa Bennett is an outreach intern for NOAA's Office of National Marine Sanctuaries and a graduate student at UNC Chapel Hill.