Cape Cod towns are on alert after more shark sightings.
Half a dozen sharks were spotted on Monday by a team of researchers led by marine biologist Dr. Greg Skomal.
"We had three sharks that were previously tagged, which gives us a really nice sense of, you know, residency, how long they stay around the area," he said.
Sharks were spotted close to shore in Chatham, Orleans and Eastham.
The sightings posted immediately to the Sharktivity App, which is produced by the Atlantic White Shark Conservancy.
"The one off of North Beach Island in Chatham was between 25 and 50 yards offshore," said Cynthia Wigren, Atlantic Shark Conservancy. "And there were people on the beach."
Experts said most beach goers are blissfully unaware. They only learned the news after the alert was issued.
"It's definitely not unusual for us to see the sharks very close to the shoreline," Skomal said. "That is not new. We've been seeing that every year for the last several years, you know. What's important for us is to get that out to the folks."
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