It's a popular week at the beach, and not just for people.
The warning flags are up, a sure sign that the sharks are out there and swimmers should take precautions.
"I'm very scared of them," said Maddie Cook of New York, who was at Nauset Beach in Orleans on Tuesday. "I mean, everybody's like, 'They may not hurt you,' and I'm like, 'They will.'"
Sixteen great white sharks have been spotted off Cape Cod in the past week, according to the Atlantic White Shark Conservancy, which tracks them on the Sharktivity app.
"I feel like every other week they're right off Nauset Beach," said Mike Romanko of New Jersey.
There were reports of one feeding on a seal off Nauset Beach on Monday.
"About 40 yards out from the beach," said Martha Schirippa of Texas. "It was pretty scary, and the lifeguards ran down just to make sure everything was kosher, but yeah, that had me freaked out a little bit, just a little bit. Had a little 'Jaws' moment there."
Researchers say the sharks are right on cue. They usually start trickling in around June and are known to swim here in search of food through October.
Experts say there's no need to call your Fourth of July swim off, but they don't recommend going in more than waist deep.
"We can swim in this whole big ocean together. There's plenty of room," said Chris Barry of Orleans.
Head of the Meadow Beach in Truro was closed for an hour on Monday, however, after a shark was seen swimming near shore. And on Friday, a shark was spotted near swimmers at Provincetown's Race Point Beach.