Massachusetts swimmers on edge after shark sightings

BOSTON (Reuters Life!) - A string of shark sightings over the past few weeks has rattled swimmers in Massachusetts at the height of the summer vacation season and sparked memories of the "Jaws" movie hysteria.

Officials in the town of Chatham on Cape Cod have warned beach-goers to stay close to shore after "numerous" sightings of great white sharks.

"Swimmers should exercise caution while swimming in Chatham's ocean waters," the harbormaster's office said in a notice posted on Chatham's website.

The town "is strongly suggesting that beach-goers and swimmers pay close attention to their surroundings while in the water, and to not venture too far from shore. If a shark is sighted, please get out of the water."

People have been prohibited from swimming within 300 feet of seals along Chatham's oceanside waters because seals often attract sharks.

The infamous great white shark can reach about 20 feet in length and weigh some 5,000 pounds.

On Tuesday, a great white shark was tagged off South Beach in Chatham during a Massachusetts Division of Marine Fisheries expedition.

At least three others were spotted close to one of the popular beaches there, and authorities warned that further sightings should be expected.

Perfect beach weather in recent weeks has seen vacationers flock to the Massachusetts shore, and above-normal water temperatures have encouraged more beach-goers to venture into the normally chilly ocean.

On Friday, swimmers at Salisbury Beach north of Boston were ordered to stay close to shore for a few hours after a fisherman reported a possible shark sighting.

That sighting was unconfirmed, but others have occurred off Gloucester, near Salisbury, and off Scituate, south of Boston.

"Jaws," the quintessential summer movie thriller from 1975 about a man-eating great white shark, was filmed on the island of Martha's Vineyard off Cape Cod.

(Reporting by Ros Krasny; Editing by Jonathan Oatis)