For Martina Mastromonaco, Chilmark beach superintendent, the horseshoe she found recently on a dune at the west end of Lucy Vincent Beach is no lucky charm.

On the contrary, she thinks the ancient-looking piece of metal is a bearer of bad tidings. The game of throwing horseshoes at the beach has not been popular for many years, she reasons, so the fact that the ocean has uncovered this artifact now is a stark illustration of how fast her beach is disappearing.

Lifeguards made a series of rescues this week at Lucy Vincent Beach in Chilmark, where rip currents have created unsafe swimming conditions in spots, Chilmark beach superintendent Martina Mastromonaco said yesterday. On Monday, two women were rescued by lifeguards after currents pulled them out to sea.

As the Atlantic Ocean continues its assault on the south-facing shoreline of the Vineyard, Lucy Vincent Beach in Chilmark has been turned into a hazard zone, its once-broad sweep of sand now chewed away by ocean waves and littered with pieces of collapsed cliff.

“The conditions are extremely dangerous, even for an experienced person like myself,” said Chilmark beach superintendent Martina Mastromonaco yesterday. “I think my biggest concern right now is keeping people away from the area.”