A California sea lion dives in search of rockfish in the waters above Cordell Bank. (photo: Gulf of the Farallones NMS)

An elephant seal checks out an observer before disappearing beneath the surface again. Elephant seals are known to be able to dive to at least 5600 feet. (photo: Gulf of the Farallones NMS)

Humpback whales engage in cooperative lunge feeding on krill-tiny crustaceans abundant over Cordell Bank. These baleen whales filter the tiny shrimp-like animals from the water column in big mouthfuls. (photo: Dan Shapiro)

Two giant blue whales, near 100 feet each in length, appear at the surface of Cordell Bank before they resume diving. The thick tale stalk and the two raised blowholes are characteristic of blue whales, as is their mottled blue-gray color. (photo: Dan Shapiro)

Speedy Pacific white-sided dolphins skim the surface waters of Cordell Bank as they race to join others from a herd of 100. These dolphins typically travel in large groups and will join fast-moving vessels to ride the bow waves. (Photo John Calambokidis)

Yellowtail rockfish cluster in schools above the densely covered pinnacles of Cordell Bank. (photo: Cordell Bank Expeditions)

A mixed species school of rockfish hang mid water in the boundless blue ocean above Cordell Bank. (photo: Cordell Bank Expeditions)

A rosy rockfish rests near yellow sponges and strawberry anemones on the bottom at Cordell Bank. (photo: Cordell Bank Expeditions)

A giant ocean sunfish, or mola mola, cruises slowly through the water column. At the surface these unusual-looking fish will sometimes be mistaken for a shark because of their tall dorsal fins. (photo: Gulf of the Farallones NMS)

Canary rockfish are a prized catch for sport fishers at Cordell Bank. (photo: Tony Chess)

A leatherback turtle comes in closer for a better look. Lucky viewers may sometimes see leatherback turtles swim in the waters above Cordell Bank. They are often found in water masses that hold gelatinous zooplankton, their favorite food. (photo: Gulf of the Farallones NMS)

Legions of seabirds feast on the abundant food resources present at Cordell Bank. (photo: Gulf of the Farallones NMS)

Multitudes of Sooty Shearwaters sit on the surface, resting between foraging sessions, at Cordell Bank. (photo: Jamie Hall)

Two Common Murres. Males leave the nest with flightless chicks and teach the young how to survive. (photo: Dan Howard)

A close-up detail of the spines of a red sea urchin. These animals can live to be 20 years old. (photo: Gulf of the Farallones NMS)

Tiny strawberry anemones stretch their starry crowns of tentacles to catch prey from the food-rich currents. (photo: Cordell Bank Expeditions)

A jewel-like top snail pictured with some closed strawberry anemones on the surface of Cordell Bank. (photo: Cordell Bank Expeditions)

A bizarre-looking polychaete worm extends its tentacles from its tubular home. The fan of tentacles filters food from the passing waters. (photo Cordell Bank Expeditions)

Orange cup coral appears brilliant on Cordell Bank. One of the few relatives of the true corals in California waters. (photo: Cordell Bank Expeditions)

Juvenile rockfish swarm over the invertebrate-covered pinnacles of Cordell Bank, far from protective cover early in life. (photo: Cordell Bank Expeditions)

A fiery explosion of sea cucumber tentacles is often all one can see protruding from rock crevices. Tentacles trap small organisms and detritus from the water. (photo: Cordell Bank Expeditions)

At the top of a pinnacle, yellow sponges and pink anemones dominate the cover of Cordell Bank. The white rope is being used by the researcher taking the photograph to document the species occurring along a transect line. (photo Cordell Bank Expeditions)

A stream of gelatinous zooplankton in this case a siphonophore-drifts through the water column. Siphonophores can reach up to 30 feet in length. (photo: Gulf of the Farallones NMS)

A close-up of a euphausiid shrimp, commonly known as krill. These tiny (less than 1 cm) animals cluster together in great clouds and are fed upon by everything from huge whales, to seabirds, to fish. (NMFS, La Jolla)

A lion's mane jellyfish pulses through the surface waters near Cordell Bank. The productive waters of this region yield many different kinds of gelatinous invertebrates.(photo: Gulf of the Farallones NMS)

Aggregate salps in water near Cordell Bank. Salps have some of the fastest reproductive rates documented for any animal. (photo: Gulf of the Farallones NMS)

A pteropod, or sea butterfly, flutters through the water column. This snail has adopted life in the water column and internalized its hard shell. (photo: Gulf of the Farallones NMS)