Charting the Waters at Cordell Bank

Until 1978, no diver had explored the Cordell Bank. This extraordinary place is now a National Marine Sanctuary. There’s an interesting history behind how this part of the ocean off the coast of California, northwest of San Francisco became a sanctuary.

The bank was discovered by George Davidson while conducting surveys along California’s north coast in 1853. Sixteen years later, in 1869, a more extensive survey was conducted by Edward Cordell, after whom the bank was named. What follows is some of the experiences shared by the first divers to view the bank.

At 150 feet, air bubbles slide out of my regulator sounding like gravel being poured from a metal bucket. We are 20 miles from the nearest shore on a ridgetop of a large Pacific seamount named the Cordell Bank and the scene below is incredibly bright. Anemone, hydrocoral, sponges, and algae cover everything in sight, in many places growing on top of each other.

While collecting some of these organisms, we are suddenly flushed with a euphoric giddiness. We try to smile, but numb lips and the regulator make the effort that much sillier. Struggling to control the narcosis, we keep collecting and exploring. All too soon, however, my buddy waves a thumbs-up in front of my mask. Now, where’s the ascent line? A flashing strobe catches my eye and I swim toward it. The line’s there, so we follow our bubbles – but not to the surface. At 10 feet, we both grab the regulators of full scuba tanks. The decompression wait seems eternal as we can hardly wait to tell the others about our dive to where no one has been before.

These experiences were shared with the author from Robert Schmeider, Ph.D., of Walnut Creek, California, who was obsessed with the exploration of Cordell Bank. In 1977, while studying a chart of northern California’s coastline, this atomic physicist became intrigued by Cordell Bank, which is 20 miles (32 km) due west of Point Reyes and to the northwest of San Francisco. The chart showed there was at least one shallow place with a depth of 20 fathoms or 120 feet (37 meters). It could be dived using regular scuba tanks, so Schmeider assumed it had been. But when he asked a few diving friends if they had ever been there, he discovered none had. So he talked to people with the Coast Guard, the Navy, the California Academy of Sciences, the University of California at Berkeley, the Department Fish and Game, the Geological Survey, the National Oceanic and Atmospheric Administration (NOAA) and others. After a couple of months, Bob realized to his amazement, no one knew much about the bank at all. The idea of exploring Cordell Bank soon became a serious goal.

But Bob expected many dangers. Deep-diving can always be dangerous, especially with compressed air scuba diving due to the possibility of nitrogen narcosis and decompression problems. Additionally, he knew the water was cold, and a fairly stiff current of one or two knots ran in the area. Two knots is nearly impossible to do any work in. To make matters even worse he expected to encounter lots of sharks, including great whites since Cordell Bank lies about midway between Tomales Bay and the Farallon Islands, both places where great whites are known to congregate.

The fisherman in Bodega Bay knew the Bank well as an excellent fishing area, so Bob lined up a boat and skipper from there. After extensive discussions with several of his regular diving partners, he announced his plan to divers in the Sierra Club’s Loma Prieta chapter from the San Francisco Bay area in October of 1977. He knew exploring the bank would require a large support group. At an organizational meeting held in the U.S. Geological Survey chambers in Menlo Park, the group elected a divemaster and all but one of the 40 people attending pitched in $40 a piece to kick off Cordell Bank Expeditions.

After a few practice dives at Monterey and at the Farallon Islands, Bob felt his group was ready to go to Cordell Bank. Unfortunately, he ran into numerous difficulties. Most importantly, a number of divers had dropped out of the group, so Bob had trouble gathering enough divers for a trip. Finally, on October 20, 1978, with just five divers, Bob made it to Cordell Bank.

As Bob recalls, “What we saw on that day absolutely astonished us. We were totally unprepared for the light level. Not only was it not dark, it was incredibly light. After I made the first dive with a buddy, I told the other drivers not to take their lights, as they simply would not need them. It was so light you could almost read. And we had been to a depth of close to 150 feet.”

“There were enormous aggregates of 12-inch (30 cm) fish swimming around above the pinnacle. To us, it seemed an incredible snowstorm of fish. When we finally broke through the fish on our way down, our entire field of vision was just filled with this miraculous sight. We could see colors – reds and oranges and yellows – and the rocks were covered, just inundated, with organisms. Sponges, especially Corynactics (Strawberry anemone), pink hydrocoral, hydroids, and a lot of large-bladed algae. It looked as if someone had landscaped it. We were just overwhelmed.”

On the first dive, they collected nearly 50 species, including at least one new genus of algae and one new species. By working closely with a number of professional biologists at the University of California at Berkeley, the California Academy of Sciences, the Los Angeles County Museum, the Geological Survey, the Smithsonian, and other institutions, they sorted and identified their new collections until the list included more than 400 species.

After that first dive, made possible by the Sierra Club divers and by grants from such organizations as the San Francisco Foundation and the National Geographic Society, the Cordell Bank Expeditions evolved into a member-supported, systematic, data-gathering organization that bought its own research vessel, the Cordell Explorer, which was retired in 2014. They bought a LORAN-C receiver and carried out depth surveys back and forth across certain areas, measuring depths and recording positions. From that data, they were able to generate their own set of charts. Those charts became a major help in carrying out more successful dives, as they could more reliably find the pinnacles and ridges they wanted to dive. In the summer of 1985, Bob and a colleague were able to obtain state-of-the-art hydrographic survey data on the Bank as a result of a project conducted by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS). That survey covered the 200-mile Exclusive Economic Zone (EEZ) off the coast that the U.S. claims control over. Cordell Bank may well be the best-surveyed feature off the coast of North America.

Aside from collecting specimens and surveying, the expedition also used 35-millimeter photography, plus Super 8-millimeter, 16-millimeter, and videotape cinematography. Some of their photographs have been useful in identifying species that didn’t show up in their collections and in showing physical features the divers may not have noticed during their dives.

They have found this seamount is roughly elliptical and, at the 50-fathom depth, it is 9-1/2 miles long by 4-½ miles wide (15.3 x 7.25 km). It lies right on the edge of the continental shelf and is the northernmost such shallow place all the way to Canada. The bank is a distinct plateau with its flat top rising to the 30- to 35-fathom depth. Atop this plateau, at least four cliffy ridge systems, two in the north and two in the south, and several pinnacles reach to diveable depths. In fact, the shallowest point the expedition has found is about 19 fathoms (114 feet or 35 meters) and is part of a ridge system in the northeast. Geologically, it is considered a piece of the ancient Sierra Nevada that was sheared off by the Pacific Plate, thus explaining its granite composition.

Growing on this 19-fathom peak is a dense, whitish cap of barnacles and red algae. Below this, from 20 to 25 fathoms (36.6 to 45.7 meters), the sessile community grades to nearly foot-thick piles of sponges, anemones, including the common Strawberry Anemone Corynactis californica, California Hydrocoral Allopora californica, hydroids, and tunicates. Space is the limiting factor. The organisms are very brightly colored with reds, yellow, white, and pinks. At 30 fathoms (55 meters), the community thins to a few large, widely spaced creatures, mainly sponges, urchins, and anemone. By 35 fathoms (64 meters), bare rock dominates the scene. Around 200 feet in various places, brilliant white sediments of almost a hundred percent shell fragments accumulate.

The Cordell Bank community is very healthy showing little evidence of disease or death because the California Current brings clean, clear, cold (50 to 55 degrees F. or 10 to 13 degrees C.) water, with a high nutrient content, upwelling to the relatively shallow bank. When the disruptive El Niño current occurs off California’s coast, the water temperatures at the bank rise to over 60 degrees F. or 15.6 degrees C. The sun’s rays penetrate this water so deeply divers can take photographs using available light at 150 feet (46 meters). Visibility is sometimes as good as 100 feet (30.5 meters). Because of the water’s clarity and nutrient load, photosynthesizing organisms support a vast and complex food chain up to large fish, birds, and mammals.

Cordell Bank has long been known as a superb fishing area. Groups of rockfish congregate around the pinnacles, sometimes so thickly, divers report whiteout conditions. Besides rockfish, sport fishermen regularly catch lingcod, yellowtail, salmon, albacore, and shark. Oddly enough, the divers have yet to see great white sharks, in spite of the fact that the great white’s favorite prey, seals and sea lions, are at the bank. They have, however, seen blue and mako sharks.

Like rockfish, seabirds often congregate around the pinnacles, and it was just such gatherings that enabled the expedition to initially home in on shallow points to dive. On surveying and diving trips since 1978, volunteer observers from the California Marine Mammal Center and San Francisco State University have recorded many sightings of seabirds and mammals at or near Cordell Bank. They’ve seen 33 species of seabirds including black-footed albatross, northern fulmar, surf scoter, south polar skua, common murre, pigeon guillemot, tufted puffin, and brown pelican. The previously endangered brown pelican was particularly noteworthy because it was sighted on about two-thirds of the trips.

The observers also recorded fourteen kinds of marine mammals. Of special interest were two endangered cetaceans, the humpback and blue whales. Both species feed at the bank. The team’s most exciting encounter with blues occurred on October 10, 1982, when a pair approached from off the port bow, surfaced 30 yards away, visibly swam under the ship, and surfaced again several hundred yards astern. Marc Webber and Steven Cooper, reporting for the group, felt the number of blue whale sightings “represents a substantial number of records for this species over the continental shelf in the Cordell Bank area, and along with probable observation of feeding suggest this area is an important autumn habitat for this species.” Also of particular interest were sightings of northern elephant seals whose pelagic habits have only recently become better understood. Other observed mammal species were Minke whale, Dall’s porpoise, harbor porpoise, orca, Pacific white-sided dolphin, Risso’s dolphin, Northern right whale dolphin, California sea lion, Steller sea lion, northern fur seal, and harbor seal. These have all been autumnal observations. The expedition has restricted their trips to the autumn because the weather is most predictable at that time and because the California and Davidson currents more or less cancel each other out, which makes diving more practical.

The greatest mysteries Bob and his divers have encountered are a number of large, cylindrical holes that lie right on the sharpest, highest parts of the region. Some holes appear to be man-made, but others look natural. Hearsay has it the holes were made by the U.S. Navy during the 1960’s in a project related to submarine detection. Bob’s expedition was once followed for nearly an hour by an unidentified submarine. In spite of his security clearance, Bob has been totally unsuccessful in learning anything from the Navy about any of this.

Cordell Bank is now a national marine sanctuary. The Sanctuary Programs Division (SPD) of NOAA, which is in charge of the sanctuaries program held its first informational hearing on the bank in San Francisco on April 25, 1984, and published a draft Environmental Impact Statement and other documents.

Bob is optimistic about Cordell Bank’s future. He believes, “It’s incumbent upon those of us who wish to preserve certain areas of our environment like museums, to set up the legislation to protect those areas. We don’t give any thought whatsoever to commercially developing Yosemite because it’s become part of our national environment, our cultural heritage. And our marine sanctuaries will become the same way. I hope and believe that 50 or 100 years from now, areas like Cordell Bank, which had long since been designated marine sanctuaries, will be part of our national heritage and will be considered inviolate.”

Creating a Marine Sanctuary

The federal marine sanctuaries program was established by Title III of the Marine Protection, Research, and Sanctuaries Act of 1972. This law provides that areas in the ocean as far out as the edge of the continental shelf and in the Great Lakes may be protected.

During its first 5 years, the program crawled slowly along, because no funds were appropriated. By 1977, only two marine sanctuaries had been designated. The first was a six square mile site off Cape Hatteras, North Carolina, to protect the wreck of the U.S.S. Monitor, and the second was Key Largo Coral Reef Marine Sanctuary adjacent to John Pennekamp Coral Reef State Park in the Florida Keys, which covers 100 square miles. In that year, 1977, President Carter, in an environmental message to Congress, expressed support for the program and boosted funding. In contrast to the law’s original intent, Carter was trying to protect areas threatened, in this case, by offshore oil development. As it turned out, one of Carter’s last official acts was the designation of three new sanctuaries: Looe Key in Florida, Gray’s Reef in Georgia, and the Gulf of the Farallones off California. (Cordell Bank neighbors this sanctuary.) Once again, the program was slowed by restricted funding under the Reagan Administration.

The slowness of the marine sanctuaries program was especially disheartening because all the land is under state or federal control already and doesn’t require acquisition funds. Money was needed only for evaluating potential sites, managing a site after it becomes a sanctuary, and enforcing the protective laws.

The marine sanctuaries program works in the following way. Any organization or member of the public may send nominations to the Sanctuary Programs Division (SPD) in the Commerce Department’s National Oceanic and Atmospheric Administration (NOAA) for consideration. The idea of nominating a place need not be intimidating. As Bob Schmeider found out, “the nomination itself doesn’t need to be very specific at all. Of course, if the (SPD) already knows about a site, which they had already known about Cordell Bank from information I had given them well before the nomination, (then) the actual nominating step was simply a letter from me to them saying I would like to nominate Cordell Bank. If a site is totally unknown and you’re preparing a nomination, then you need to include some details and some information, so that they will have some knowledge of it. That’s all.”

Formerly, a nomination was automatically placed on a List of Recommended Areas, but this has been replaced by a Site Evaluation List (SEL) that includes nominated sites meeting certain preliminary criteria. After review by the SPD staff, the SPD can promote the area to active candidacy. At that point, they’ll produce draft documents, including a management plan, environmental impact statement (EIS), and a designation document. These will be circulated among interested individuals, organizations, and governmental agencies. They’ll also schedule public hearings in the communities nearest the candidate site to get additional input. From that, they’ll produce final documents and circulate those and hold more hearings. Congress has the opportunity to review a site’s candidacy and hold their own hearings. Cordell Bank was the first marine sanctuary candidate to receive such scrutiny. If the site is within state jurisdiction, then that state’s governor may veto the designation, but this won’t necessarily cancel a site’s candidacy altogether. (Cordell Bank wasn’t in state waters.) After all of these steps, the Secretary of Commerce can sign the designation document and the site will become a national marine sanctuary.

Cordell Bank was established as a marine sanctuary in 1989 and expanded in 2015 to cover 1286 square miles.

The official government website for Cordell Bank is at: http://www.cordellbank.noaa.gov, while the Cordell Bank Expeditions web site is at: http://www.cordell.org.