Conservation & Science

New kids on the block

Monterey Bay and surrounding waters are prime habitat for white sharks. The same adult white sharks visit this part California annually over decades, mostly during fall and early winter. Farther south, from Santa Barbara to Central Baja, white shark babies, or pups, typically spend their first years in warmer “nursery” waters.

The cohort of young white sharks close to popular Santa Cruz County beaches has sparked Monterey Bay Aquarium researchers to investigate what’s drawn them to the area. Photo © Giancarlo Thomae Photography

What’s new and surprising, though, is that in recent years a seasonal group of younger white sharks has established itself within sight of the beaches at the north end of Monterey Bay. Is this new cohort taking up residence as a result of warming ocean conditions? And why are the sharks aggregating in one portion of the bay?

That’s what Monterey Bay Aquarium research scientist Dr. Sal Jorgensen and his colleagues hope to determine in the coming months.

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For white sharks, an oasis, not a desert

This spring, a diverse team of ocean scientists headed to the middle of the Pacific Ocean, seeking to explore the vast and mysterious home of one of the world’s top ocean predators: the white shark.

White sharks tagged along the California coast guided researchers to the offshore waters where they spend half the year. Photo by Steven K. Webster/Monterey Bay Aquarium

Guided by the sharks and their need for a steady supply of food, the researchers sailed into the heart of what was once deemed an oceanic “desert.” They discovered that the open Pacific, particularly an expanse dubbed the White Shark Café, teems with abundant and unusual life forms—organisms that may help explain the fascinating behaviors of white sharks on the high seas.

“The Café is far from the desert it was thought to be,” says Aquarium research scientist Dr. Sal Jorgensen. “It is home to an abundance of life that satellite imaging is not detecting. In fact, for white sharks, it is more of an oasis.”

Researchers spent a month at the White Shark Café aboard the Schmidt Ocean Institute’s R/V Falkor. Photo courtesy Schmidt Ocean Institute

The White Shark Voyage team embarked from Honolulu for a month-long journey aboard the Schmidt Ocean Institute’s R/V Falkor and traveled east to waters halfway between Hawaii and Mexico.

Headed by principal scientist Dr. Barbara Block of Stanford University, the research team aboard the Falkor included marine biologists, engineers and oceanographers from Monterey Bay Aquarium, Stanford, Monterey Bay Aquarium Research Institute (MBARI), University of Delaware, NOAA, Montana State University and ocean tech innovator Saildrone.

While no one knew what they’d find, everyone hoped to gather insights about what might be driving the behaviors of white sharks, and what role this offshore habitat plays in the lives of these apex ocean predators.

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New insights to help young white sharks survive

What can scientists studying white sharks learn from an expert on mountain lions? As it turns out, quite a lot.

Monterey Bay Aquarium and its research colleagues have been tagging juvenile white sharks in southern California since 2002. Now they’ve gained new insights into white shark survival from those data tags. Photo courtesy Steve McNicholas

Such a collaboration is on display in new research published in the Journal of Applied Ecology. Models that estimate survival rates for top predators on land, according to the study, can also work in the ocean. The research also revealed important safeguards that can help protect white sharks while they’re young and vulnerable.

At the heart of the effort was the work of lead author John Benson. Before taking his current role as a professor at the University of Nebraska, John was a post-doctoral researcher at the Monterey Bay Aquarium, working with senior research scientist Sal Jorgensen.

Young white shark on exhibit at Monterey Bay Aquarium.

“We always learn things from adjacent fields,” says Sal, who specializes in white sharks, and who coauthored the paper along with six others. “John made his name studying mountain lions in Southern California.”

John’s past work also involved black bears in Louisiana, panthers in Florida, wolves and coyotes in Canada, and moose and their various predators in Alaska. After so much experience on land, John saw working with Sal at the aquarium as a chance to—as the saying goes—get his feet wet. Read more…

Voyage to the White Shark Café

For nearly 20 years, researchers from Monterey Bay Aquarium and Stanford University have fitted electronic tracking tags on adult white sharks each fall and winter along the California coast around San Francisco Bay. Each year, the tags documented a consistent migration by the sharks to a region more than 1,200 miles offshore—halfway to Hawaii—that’s been considered an oceanic desert. They dubbed it the White Shark Café, guessing that opportunities to feed and to mate might be the draw.

Now a team of scientists will spend a month at the Café in a month-long expedition to learn why the sharks make an epic annual migration to such a distant and seemingly uninviting location. The multi-disciplinary team is bringing an impressive complement of sophisticated oceanographic equipment, from undersea robots and submersibles to windsurfing drones that will search signs of sharks and their possible prey.

Funded by the Schmidt Ocean institute (SOI), the team is led by Stanford University Professor Barbara Block and includes marine biologists and oceanographers from Stanford University, Monterey Bay Aquarium, Monterey Bay Aquarium Research Institute (MBARI), the University of Delaware, and NOAA’s Office of Ocean Exploration and Research.  They are traveling aboard the SOI research vessel Falkor and set sail from Honolulu on April 20. They will return to port in San Diego on May 19.

Unraveling a mystery

We’ve studied these sharks for nearly 20 years, and they’ve told us consistently that the White Shark Café is a really important place in the ocean—but we’ve never known why,” said Dr. Salvador Jorgensen, a senior research scientist and shark research lead at Monterey Bay Aquarium.

Sophisticated oceanographic monitoring tools like these Saildrones will collect data to document the presence of white sharks and their prey species in the cafe. Photo courtesy Schmidt Ocean Institute.

By documenting the biology, chemistry and physical conditions in the region—a swath of the Pacific Ocean the size of Colorado—the researchers hope to understand what makes the Café an annual offshore hot spot for one of the ocean’s most charismatic predators. Read more…

International partnership confirms a new Baja nursery area for white sharks

It’s relatively easy to spot when and where a pregnant animal gives birth on land. But in the sea, it’s a whole different story.

Over the past few decades, researchers studying the elusive great white shark have pieced together a picture of their underwater lives: The adults seasonally travel between a remote region of the Pacific Ocean—dubbed the White Shark Café—and their feeding grounds in Central California and Mexico.

But where do females give birth, and where do the offspring grow up?

Researchers in Mexico and the United States, including a team from the Aquarium, have confirmed a new nursery area for white sharks on the Pacific Coast of Baja California.

“We don’t know whether [the sharks] pup in-shore or off-shore,” explains the Aquarium’s Director of Collections John O’Sullivan. “We don’t even know whether they pup in American or Mexican waters.”

But in a paper recently published online in the journal Fisheries Research, scientists have revealed a new piece of the juvenile white shark puzzle. The study—an international collaboration between researchers at the Ensenada Center for Scientific Research and Higher Education (CICESE); Monterey Bay Aquarium; California State University, Long Beach; and other institutions—revealed that Bahia Sebastian Vizcaino, a warm lagoon on the coast of Baja California, is a nursery area for newborn white sharks.

The bay, part of a protected biosphere reserve and a prime breeding ground for gray whales, is located on the west coast of the Baja Peninsula, 500 miles south of San Diego. Read more…

Dispatch from the Farallones: White shark family portraits

Monterey Bay Aquarium’s white shark tagging team recently made its annual visit to the Farallon Islands outside San Francisco Bay. The goal: to continue its long-term efforts to monitor a genetically distinct population of adult white sharks, which gathers at the islands each fall to gorge on seals and sea lions.

 During the trip, team members took photos to identify individual sharks by their dorsal fin patterns, collected tissue samples for genetic research, and attached electronic tags to study these majestic ocean predators. Presley Adamson, associate producer and editor for the Aquarium’s film team, reports back on his experiences in the field.


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Approaching the Farallones.

It’s been two hours since we lost sight of the Golden Gate Bridge and, with it, any sign of civilization. Dr. Salvador Jorgensen, senior research scientist for Monterey Bay Aquarium; and Scot Anderson, a pioneering white shark expert and seasonal researcher for the Aquarium, are somehow sleeping through the relentless rocking and rolling of our sailboat. I’m too excited to sleep.

Choppy waves have kept us stuck on shore for six straight days. Today, the waters are finally calm enough for us to cross the 25 miles of open ocean between San Francisco and the Farallon Islands.

The Farallones are technically part of the City of San Francisco, but we won’t find any subdivisions or grocery stores here. The islands, their surrounding waters, and their plant and animal inhabitants are protected in the Farallon National Wildlife Refuge, within the Greater Farallones National Marine Sanctuary.

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A whale fluke surfaces near our sailboat as we near the Farallon Islands.

More elephant seals and sea lions than people visit the Farallones. The abundance of blubbery pinnipeds attracts some of the largest white sharks in the world, who hang around the islands looking for a meal.

Sal and Scot have brought me along to document this year’s research season. I’m armed with six cameras that need to be set up before we get to the Farallones. I also need to put on foul-weather gear—boots, life jacket, raincoat, and other gear to stay warm and dry. But I’m distracted by a pod of humpback whales next to our boat, showing off their giant flukes as they go about their own morning commute.

I can just start to make out a lone pinnacle emerging from the sea. We’re almost there.

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The spooky science of shark mummies

John O’Sullivan, the Aquarium’s Director of Collections, was in Mexico on a mission. A young white shark equipped with an electronic tag had traveled over 650 nautical miles south from its release point in Monterey Bay, and the tag had popped off somewhere along the central coast of Baja California. The tag contained a complete data set documenting the shark’s movements and physiology since its release, and John aimed to recover it.

Instead his guide, a local fisherman, led John to a shark graveyard.

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Location of shark dump site in Baja California, Mexico.

A grisly grimace

Sometimes, commercial and sport fishermen accidentally ensnare juvenile white sharks off the coasts of California and Mexico. But locals in some communities consider it bad luck to discard the unmarketable parts, such as the heads, back into the ocean. Instead, they deposit these shark parts at dump sites in the Mexican desert.

In central Baja, just north of Guerrero Negro, John and a team of local Mexicans encountered hundreds of shark heads, in various stages of decay. Some were fresh; others were rotting. Some had skin that was dry and well-preserved—in other words, mummified—in this arid location.

Many of us would turn away from that gruesome sight. But John and his colleagues looked into the mouths of the shark-head mummies and saw an opportunity.

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