Swimmers were ordered out of the water at the Head of the Meadow Beach in Truro after researchers spotted a great white shark swimming near them on Monday, according to the Cape Cod National Seashore.
In a posting on the app of the Atlantic White Shark Conservancy, rangers from the seashore said there was a “confirmed shark report from life guard [and] plane circling over head. . . . Swimming closed for one hour.”
The item was posted around 12:45 p.m.
About a half-hour later, four great white sharks were spotted farther up the coast, near High Head Beach, between Truro and Provincetown, the research organization tweeted.
The cluster of sharks near Truro and Provincetown was spotted about two hours after researchers led by Gregory B. Skomal, the state’s shark expert, successfully tagged the fifth great white shark of the 2018 research season. A photograph of Skomal, who works for the state Department of Marine Fisheries, was posted by the conservancy on its app and website.
The tagged shark was about 12 feet long, the group tweeted.
The tagging was one of six great white sightings reported off the Cape Cod coastline on Monday. It was not immediately clear if some of the sightings involved the same animal.
Each year, Skomal and the conservancy travel along the Massachusetts shoreline hoping to tag sharks and install data collection devices. During the past several years, the partnership has resulted in the tagging of about 100 great whites.