REVERE – When word spread earlier this month that piping plover chicks had hatched on a Massachusetts beach, most bird lovers assumed the nesting area was in Ipswich, not Revere.But in an unprecedented turn of events, two piping plovers n listed by both the state and federal government as a threatened species n were born in the sand on America’s first public beach. The birds found protection beneath snow fencing erected by the state Department of Conservation and Recreation (DCR) as part of Revere’s ongoing beach restoration project.Piping plovers are rare, tiny shorebirds that often migrate and nest along protected areas of Crane Beach and Plum Island in Ipswich. Their annual presence translates to the temporary closure of those beaches to the general public.Lisa Capone, spokesman for the state Executive Office of Energy and Environmental Affairs (EOEEA), said the state Division of Fisheries and Wildlife, in concert with organizations such as Mass Audubon, have worked hard to restore the plover population.”The species presence on Revere Beach underscores the beach’s renaissance as a natural resource for Greater Boston and the North Shore,” said EOEEA Secretary Ian Bowles, who visited the beach to witness the hatchlings.Bowles said those who monitor wildlife expect piping plovers in remote places like Sandy Neck and Crane Beach, but finding this threatened species in an urban landscape like Revere was a remarkable surprise.Massachusetts supports about 15 percent of the world’s population of piping plovers, found in dunes from Newfoundland to North Carolina. A census conducted 20 years ago indicates there were 139 pairs of piping plovers in Massachusetts. The number of pairs has since grown to 482, based on last year’s count.”We’re delighted that the plovers have chosen Revere Beach as their latest habitat,” DCR Commissioner Rick Sullivan. “We’ve taken steps to protect them until they can fly.”Becky Harris, director of Mass Audubon’s Coastal Waterbird Program, described finding piping plovers on Revere Beach as unprecedented. “It’s amazing that they chose to next on a heavily-used urban beach n in fact, the oldest bathing beach in the country,” she said. “It’s an indication that, with appropriate management and protective measures, we can have successful plover nesting and public use.”