The Return of Jaws

The alarm went up after two fishermen made two separate reports of great white sightings. Both described their shark as wide and about 15ft long. Buddy Vanderhoop said he saw the telltale dorsal fin 500ft off a beach in early evening. Scott McDowell, the skipper of a charter fishing-boat, also claimed he had seen a shark.

Last week, town officials closed beaches then reopened them. First the 2ft 6in dorsal fin of a shark was spotted, 75 yards off South Beach. Then lifeguards doing their morning training reported seeing a shark at the very place the opening scene of Jaws was filmed. A sightseeing plane, the Red Baron, also reported seeing a large shark and by the weekend concern was growing. "It creates some excitement in town," said Trish Lyman, who runs The Boneyard surf shop. "I wouldn't call it hysteria. People are tentative but still excited. I'm still renting surfboards, four of them already this morning. The truth is there are always great whites out there and they were probably drawn in by seals which have now moved away."

There are further worries for the island's tourism industry. One man has been charged with disorderly conduct for spreading panic on a state beach. He warned people to get out of the water and claimed he had seen two sharks about 22ft long while working on a fishing boat. Police concluded that the 60-year-old homeless man had been lying.

Warmer sea temperatures may be bringing more of the killer sharks into Massachusetts waters. A few years ago, a great white was trapped for two weeks in a shallow lagoon. The 14ft and 1,700lbs great white was tagged by Greg Skomal, a shark specialist at the Woods Hole research centre nearby. "That was a telling sign for us that the animals are here," Mr Skomal said.

In the 19 years of the Martha's Vineyard shark-fishing tournament a great white has never been hooked. But, as the seal population has increased from fewer than 20 in the 1970s to more than 6,000, sharks are being drawn in. After they reach 1,000lb, they give up their fish diet and hunt seals. So far, they have yet to turn their sights on humans.