REVERE — No one imagined that the tiny, threatened birds would stage a comeback on a beach where jets constantly swoop low overhead and thousands of people often pack nearly every square foot of sand.
But the state has been so successful in nurturing the piping plovers back to health on Revere Beach and elsewhere in Massachusetts that their nesting areas have begun consuming wide swaths of the state’s beaches.
The result has been happy birds and angry humans.
In recent weeks, as the sand-colored birds have arrived to roost on their eggs, the people detailed to protect them say they have been taunted, cursed at, and dismissed as flunkies of a state more concerned about birds than people. The bathers want their sandy shores back.
“A man told me the other day that he has spent his life trying to fight what we do,” said Lyra Brennan, a field technician for Mass Audubon, who has had to call on state park rangers for help as she patrols the beach with binoculars and a notebook.
When federal officials designated the region’s plovers as threatened in 1986, there were just 139 breeding pairs in Massachusetts. Since then, after spending $150,000 a year to help avert the extinction of the short-and-stocky species, the state has seen a resurgence of plovers, with an estimated 664 pairs nesting last year. That exceeds the federal goal of 625 pairs.
The success of the rescue effort has meant that more of the state’s beaches — and often more acreage on those beaches — are interlaced with fences at the time of year when people most want to use them. The plovers typically arrive from southern climes in late March, hatch their chicks, and then teach them to forage until July or later.
The tension sparked by the increasing number of protected areas is especially evident at Revere Beach, where 16 plover pairsare now in residence, nearly double the population last year and up from just one in 2007. The enclosures to protect the birds, which have set up nests near the bathhouses of a public beach that often attracts 10,000 people on a summer day, now take up 15 percent of the beach at high tide.
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A piping plover chick enjoyed feeding at Revere Beach.
Local residents have circulated petitions, asking state officials to reduce the fencing or move the birds. But federal laws designed to protect the birds forbid this, and local officials can do little but relay their concerns to federal officials.
“I believe the anger is justified,” said Representative RoseLee Vincent, a Democrat from Revere, who last month held a meeting about plovers with constituents, the mayor, and representatives from Senator Edward J. Markey’s office.
The number of calls, e-mails, and other complaints are running at four times the rate she experienced before the plover resurgence.
“People are very concerned that if the barriers keep growing, there will be none of America’s first public beach left,” Vincent said. “The barricades have grown to a point of absurdity.”
With the huge crowds, large planes flying overhead to Logan, and all the noise and wind-blown detritus of an urban beach, ecologists were surprised in 2007 when the first pair of plovers began nesting in Revere.
“We would have never predicted there would now be this many birds here,” said Jon Regosin, chief of conservation science at the Massachusetts Division of Fisheries & Wildlife. “We have learned that they aren’t disturbed by noise.”
The birds have also managed to raise significantly more chicks in Revere than elsewhere. Last year, the plovers there succeeded in raising an average of 3.3 chicks, compared with about 1.3 chicks on other beaches in the state, Regosin said.
“The incredible success in Revere is because they’re getting extraordinary protection,” said Katharine Parsons, director of Mass Audubon’s coastal waterbird program.
The birds, however, are not doing as well elsewhere.
They have struggled on less-crowded beaches across the state and throughout their range along the Atlantic coast, where there is often limited protection from predators, such as gulls and skunks. They also struggle to fledge chicks on beaches subject to erosion; narrower shores mean less room to camouflage themselves with and eggs more frequently washed out to sea.
Across their range from North Carolina to Eastern Canada, there were an estimated 1,761 plover pairs last year – down 7 percent from their high in 2007 and well below federal goals. The US Fish and Wildlife Service won’t consider removing the birds from federal protection under the Endangered Species Act until, among other signs of revival, they maintain a population of 2,000 pairs for more than five years.
But the success of conservation efforts in Massachusetts has raised questions about whether the state is preserving the plovers at the expense of people, especially in Revere.
“They’re denying us the right to use our beach,” said Cecilia Solomon, 87, one of scores of residents who live across from Revere Beach and signed a petition urging the state to take down much of the fencing. “It’s like they care more about the plovers than the people.”
Ralph Carchedi, 75, who has lived in a tower over the beach for 30 years, called the 11 enclosures on Revere “a disgrace.”
“There’s no place left for the bathers,” he said. “It doesn’t even look like a beach anymore.”
State officials have heard the complaints in Revere and elsewhere, and in an effort to maintain public support, they have sought a waiver from the federal government from some of the Endangered Species Act’s strict rules.
They said they hope that, by next year, the federal government will grant Massachusetts more flexibility, allowing cars on some beaches, parking lots to open near nests, and for state officials to move some eggs, if deemed necessary.
For now, state officials say they are trying to balance the tensions.
They have sought to make the enclosures less obtrusive, using fiberglass rods and blue signs, which they say blend in better. And they say their focus is on educating the public, rather than threatening them with fines.
But there are challenges. Kids sometimes chase the birds. Others pick them up. Some have set bonfires near the nests, retrieve balls from the enclosures, and fly kites nearby, which plovers sometimes confuse with predators.
This week, the eggs on four of Revere Beach’s nests disappeared.
“This is hard work,” said Jorge Ayub, a coastal ecologist with the state Department of Conservation and Recreation. “It’s all about striking the right balance.”
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A chick ran through the water along the shore of Winthrop Beach.