Stonington - Closed areas of Sandy Point expected to have been reopened by now remain closed to the public as terns, plovers and oystercatchers are still nesting and rearing chicks, according to a federal Fish and Wildlife Service official.

Charlie Vandemoer, the refuge manager of the Rhode Island National Wildlife Refuge Complex, said Tuesday that about 30 percent of the island, which is a popular summer boating destination, remains closed to the public.

While the plan was to decrease the number of closed areas once the shorebirds finished nesting, he said some birds were unsuccessful and have had to rebuild their nests.

He said the historically high tides in June contributed to the problem. A similar situation has occurred along Napatree Point and East Beach in Watch Hill, which is also monitored by the refuge.

"We have had several initial nest failures, so we need to be sure adequate habitat is protected until the renesting occurs," Vandemoer said. "That's also why it's important to minimize disturbance, or keep dogs away, so we can get these birds up and running, so their nesting season doesn't occur throughout the entire summer."

Some people had been allowing their dogs to run loose on the island; the dogs scare the birds or walk in areas where birds are nesting.

Vandemoer said Fish and Wildlife staff are on the island monitoring the situation and will reopen areas when they can.

"The majority of the island is still available to people," he said. "When we have the opportunity to reduce those (closed) areas, we will do that, but it is very bird dependent."

He said surveys have shown six pairs of piping plovers on Sandy Point, which is the same as last year, and eight pairs of American oystercatchers, a decrease by one from last year.

The number of least terns has plummeted from 27 to 1, but Vandemoer said terns are unpredictable from year to year, sometimes nesting on one beach one year and another the next.

"So even though the terns at Sandy Point declined this year, it would not be surprising to see them return in great numbers next year," he said.

In 2010, the island's owner, the Avalonia Land Conservancy, asked the Fish and Wildlife Service to manage the mile-long island for the next five years. It said the goal is to balance the use of the island with protection of shore birds.

Fish and Wildlife has posted rules for the public that include a ban on kite-flying, fireworks, open fires, camping, dogs, pets, possession of alcohol by minors and adults impaired by alcohol. Allowed activities include wildlife observation, swimming, sunbathing, walking, fishing, photography and cooking with gas or charcoal stoves, as long as debris is removed.

The Fish and Wildlife Service has called the effort a success, as the numbers of plovers and oystercatchers have both increased in recent years. While the population of terns has fluctuated, in 2010, surveys counted 443 pairs of least terns, which produced 400 chicks.

j.wojtas@theday.com