Just when Americans thought it was safe to go into the water for their final weekend dip of the summer, a great white shark scare has closed beaches on the northeast coast.

Despite an influx of visitors for the Labor Day weekend holiday, authorities closed five Cape Cod beaches after the predators were spotted off the coast.

Officials are in no mood to take chances, remembering, perhaps, the seventies movie classic Jaws, in which a decision to open a beach on one of the busiest weekends of the year proved fatal.

Three great whites, weighing about half a tonne each and measuring about 3 metres (10ft) long, were seen from spotter aircraft patrolling the Atlantic coast near the seaside town of Chatham.

It was not their presence that caused a stir so much as the timing. After a rainy summer in much of New England, sun and clear skies were forecast for the entire long weekend.

Tens of thousands of visitors hoped to swim in the warmest seas of the year; instead, hundreds sat on Chatham’s beaches yesterday looking for fins.

Kevin Tomany saw more than that. “I saw Jaws,” he said, after training his camera on a patch of ocean 300 metres offshore while his son was surfing off Nauset Beach in nearby Orleans on Saturday.

Hours later a biologist from the Division of Marine Fisheries made two confirmed great white sightings, one only 75 metres from Chatham’s North Beach Island.

Swimming was banned until tomorrow along a ten-mile stretch of coast — and the news networks reached for footage from the film that made Steven Spielberg’s career.

Jaws was set on the fictional Amity Island. Much of it was filmed in Martha’s Vineyard, 50 miles (80km) from Chatham, where President Obama recently had a holiday.

Great white sightings off Chatham are not unusual, because of the 7,000-strong grey seal population on nearby Monomoy Island. The first shark was reported on Thursday and the first great white was identified from an aircraft flying near the island on Friday.

On Saturday Bill Chaprales, a swordfish harpoonist, and Gregory Skomal, the state’s chief shark biologist, identified two more and tagged them with electronic devices that will record their location, and information on ambient light and water temperature, every ten minutes until January 15. The tags will then drop off and upload their findings to a passing satellite.

Mr Skomal called it a fantastic day for shark science.

Dan Tobin, the Director of Parks and Recreation in Chatham, did not anticipate much defiance of his beach closures. “People are usually pretty co-operative,” he said.

The great white has a power over the imagination of swimmers that is out of all proportion to the number of times it has attacked them.

The last fatal shark incident in Massachusetts was in 1936, when a 16-year-old boy died after being bitten in Buzzard’s Bay. His fate played a small role in emptying the waters off Cape Cod at the weekend. Hollywood did the rest.

Bite of film history

Jaws released June 1975

Opening weekend box office gross $7,061,513 Soundtrack John Williams

Body count Five humans — and a dog — are chewed up by the giant fish

USS Indianapolis In the film the shark-hunter Quint describes the fate of the warship he was on, which sank in the Second World War: “So, 1,100 men went in the water; 316 men came out and the sharks took the rest”

The story is true The Indianapolis was sunk by a Japanese submarine on July 30, 1945, midway between Guam and Leyte Gulf. The shark attacks began with sunrise on the first day and continued until the last survivors were found five days later

Source: Times database

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