There are sharks prowling the waters off the Eastern Seaboard. A lot of them.
On any given day this week, the online Ocearch shark tracker, which follows the movements of sharks and other sea creatures that have been tagged for research, recorded more than 80 great white sharks stalking the western Atlantic Ocean. The predators could be seen hugging the East Coast from New York to Florida.
In a now-viral post, one Twitter user with the handle @punished_stu joked that “sharks are amassing on the east coast,” setting off everything from curiosity to concern about the maritime congregation.
But Chris Fischer, founder of the nonprofit Ocearch, said it’s not unusual to see swarms of great white sharks off the East Coast at this time of year.
“It’s very normal,” he said, adding that sharks typically hunt in the North Atlantic before migrating south for the winter.
“They go up to New England and Atlantic Canada in the summer and fall,” Fischer said. “They forage up there, bulking up and putting on weight, and then when it starts to get cold, they move down to their winter habitat, primarily between Cape Hatteras and Cape Canaveral.”
For more than a decade, Ocearch has been tagging and tracking sharks, sea turtles, seals and other marine animals across the world’s oceans. The subjects are outfitted with satellite devices that record “pings” with location data whenever they breach the water’s surface.
Ocearch’s tracking website and app have become fun tools for citizen scientists, allowing people to follow the meandering journeys and travel logs of various sea creatures. It’s possible, for instance, to see the zigzagging paths of an adult great white shark named Caroline along the East Coast since she was first tagged in 2019. Or the less expansive wanderings of a shortfin mako shark named Fast Ball, who can be found in the Gulf of Mexico.
But in addition to providing a glimpse of ocean life to the general public, the project is gathering valuable data for the scientific community. For one, the trackers are opening a window into the once-elusive lives of great white sharks, Fischer said, enabling researchers to monitor their feeding habits, reproductive patterns and seasonal migrations year after year.
“The lives of white sharks off the East Coast of the United States are the most comprehensively studied and they’re now the most comprehensively understood white shark population in the world,” Fischer said.
The resulting database is also helping scientists keep tabs on the broader ocean ecosystem. Since great white sharks are apex predators, their health and habits can reflect reverberations further down the food chain. If certain fish or seal populations become scarce in one region, for instance, researchers could see changes in where the sharks go to hunt and feed.
Similarly, Fischer said the shark-tracking initiative is compiling information that could be used in the future to assess the impacts of climate change. Scientists could mine Ocearch’s data to see how sharks and other marine life are affected by warming waters, changing ocean circulation and other consequences of global warming.
“We’re putting a stake in the ground for climate change, because we’re documenting the movement of the sharks now,” Fischer said. “Then, 10 years from now, or 20 years from now, we’ll be able to do a project like this again and see if there’s been any shift in their migration. We’re creating that baseline data right now.”