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.
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.
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.
No ‘Silent Sea’
The Farallones may be remote, but they’re not quiet. As we close in on the largest island, Southeast Farallon, we become immersed in its soundtrack. Thousands of sea lions bark alongside chattering seabirds roosting on the steep cliffs. Massive swells crash into the island, sending mist as high into the air as a whale’s blow.
“Are you ready?” Scot shouts down the deck. I snap out of my reverie and get to work.
On the back of our sailboat rests the tagging boat, where Sal, Scot and I will spend the rest of our day. The tagging boat feels perilously tiny, considering it’s about the same length as the sharks we’re after. The sailboat crew launches the tagging boat into the sea, and tries to maintain control as it bobs uncomfortably close to the sailboat.
I wait for just the right moment to take a big step across the water and into the tagging boat. We wave goodbye to the sailboat crew, which will chaperone us at a distance until we return in the late afternoon, and we motor closer to the island.
Sal and Scot plan to place tracking tags on white sharks, and add to their ever-growing database of dorsal fin photos.
Unique as a fingerprint
“Each shark fin is like a fingerprint. It has a unique series of notches and ridges along the trailing edge that allows us to distinguish one shark from the other,” Sal explains. “We’ve been able to show that the fins remain unchanged over decades. So, if you get a good fin ID of a shark, you will be able to identify that shark 10 or 20 years later.”
Over the past decade Sal and Scot, along with colleagues from Stanford University, have identified 250 individual sharks by taking photos of their dorsal fins. The records show that many of these sharks have been visiting the Farallones for 10, 20 or even 25 years. The photos also help the researchers estimate population sizes and track migration patterns.
White sharks primarily visit the Farallones from late September to early December. A short shark season, combined with frequent winter storms, narrows the window for field research to just a few days. Sal and Scot have literally been waiting all year for this opportunity.
I quickly attach microphones to their gear and climb into the “crow’s nest,” a small platform near the boat’s console. Sal drops a piece of carpet cut into the shape of a seal onto the water, where it floats on the surface. When a shark approaches the faux seal—white sharks are visual predators, so they assume it’s the real thing—the researchers yank the carpet back into the boat.
Sal and Scot are attempting to snap photos of the shark’s dorsal fin three different ways. First, an underwater camera is mounted to the decoy, capturing video of curious sharks that may investigate but not surface or follow the decoy to the boat. Second, when a shark does break the water’s surface, Scot is ready to take photos with a still camera. Finally, Scot has an underwater video camera mounted to a pole, and films each shark when it gets close to the boat.
The decoy is out. Cameras are in position. The sea lions are still barking. Let’s do this.
A waiting game
Three hours come and go. No sharks.
Sal detects my disappointment. “A lot of days you might not see a single one,” he says. The conversation shifts to lunch.
Suddenly: “Shark up!” Scot yells, as a massive white shark breaks the surface of the water, its crimson gums and bright white teeth exposed. It narrowly misses the seal decoy.
The two researchers work in perfect coordination. Sal reels in the decoy as Scot snaps photos of the sleek black dorsal fin.
Sal recognizes this shark—dubbed “Middle-Notch,” for the shape of its fin. Scot first spotted Middle-Notch at the Farallones 15 years ago, and the team has seen him here eight other years since. The researchers have a lot of history with Middle-Notch, and they share stories about his exploits around the island.
The fin dips below the surface just behind our boat. Scot drops his still camera and switches to the underwater pole camera. Middle-Notch swims so close to our boat, I could reach out and touch him. His smooth, graceful movements around the boat barely ripple the water’s surface. I guess that’s how an animal the size of box truck can sneak up on a seal.
With every investigative circle around the boat, Middle-Notch grows less and less interested in the decoy. Sal and Scot take lots of photos and video, but they aren’t able to get another tag on him.
They’re not worried. He’ll probably be back next year.
Photos by Monterey Bay Aquarium / Presley Adamson and Angela Hains.
Featured image: A white shark, named “Middle-Notch” for the pattern on his dorsal fin, swims near our researchers in the Farallones.
Learn more about Monterey Bay Aquarium’s shark research