Great white sharks are discovering what tourists have known for years: Cape Cod is a great place to spend the summer. The latest data from a multiyear study found that the number of sharks in waters off the vacation haven is on the rise, Greg Skomal, a scientist with the Massachusetts Division of Marine Fisheries, and the state's top shark expert, tells the AP. But that's no reason to cancel vacation. The sharks are after seals, not humans, and towns are using the study's information to keep it that way. "How long does it stay and where does it go are the questions we're trying to answer," Skomal said. "But for the towns, it's a public safety issue." Researchers using a plane and boats spotted 147 individual white sharks last summer. That was up slightly from 2015, but significantly more than the 80 sharks spotted in 2014, the first year of the study, funded by the Atlantic White Shark Conservancy.
More than half the sharks spotted last summer hadn't previously been documented in the study. Researchers have tagged more than 100 to track them, though the population is probably significantly larger. "Last summer we saw greater numbers of smaller sharks, including juveniles, and that tells us that the population is rebuilding," Skomal said. Great whites come to Cape Cod to feast on seals, which used to be concentrated at the Monomoy Wildlife Refuge, but as they have moved farther north, so have the sharks. The last documented fatal great white attack in the state was in 1936. But just in case, Orleans town now flies dangerous marine life flags—with a picture of shark—every day in tourist season. "The fact that they have an eye on the situation from the air is crucial," says the town's natural resources manager. "And if they spot a shark in the swimming area, we'll close the beach." (Read more great white shark stories.)