The woods tend to be overlooked, wedged to one side of the Patriots Point attractions, past the ball fields, abutting the golf course.

Yet they are considered invaluable to migrating birds. And conservationists are alarmed.

A 25-year conservation easement that protects the woods is approaching its expiration date. The 21 acres sit in the middle of the Patriots Point Naval & Maritime Museum complex in Mount Pleasant, part of a larger tract under lease to Bennett Hospitality, a development group looking to build hotels, residences and businesses on the larger site.

Now a sign has been removed that designated a nature trail through the grove.

The site provides food, cover and a resting point for songbirds moving north or south with the season, and which tend to make a long water crossing from or to Charleston. As many as 250 different species have been spotted there, including a dickcissel, a yellow-chested bird that resembles a meadowlark.

That bird is rarely spotted in the state outside of the mountains and Midlands.

Even among a series of important habitats along the coastal Eastern Flyway, the modest patch of woods stands out enough that a bird banding station was run there for years by the Charleston Museum.

“If you designed a site and forest to optimally benefit migratory birds in coastal South Carolina, you would end up with something close to the wooded areas at Patriots Point,” said Charleston ornithologist and conservationist Nathan Dias. “It would be a tragedy to lose them.”

Dana Beach, founder of the Coastal Conservation League, added, “They (migrating birds) are looking for patches of habitat like this one, and for reasons only birds know, find some little patches a lot more appealing than others.”

The league was part of a group that worked to defuse a move in 2011 to turn over the property for development, and transferred the easement to the S.C. Department of Natural Resources for safekeeping, a decision Beach now hopes wasn’t a mistake.

DNR would have the first option whether to renew the easement, which ends in 2023.

The department “will be monitoring and reviewing the use of the property and will make a decision about renewing the easement well within the time frame laid out in the original agreement,” said spokesman David Lucas.

“We anticipate that process will include conversations with the leadership of the Patriots Point Development Authority about their plans,” he said.

The authority leased some 60 acres to Bennett’s Hospitality in 2017, a deal expected to bring the authority at least $3.34 million per year in rent revenue to meet future needs. Mac Burdette, the authority’s executive director at the time, noted the acreage included the conserved area and that the easement could be lifted in 2023.

Patriots Point’s director, Larry Murray, said the authority would meet with both DNR and Bennett Hospitality to “discuss future interests,” but that the decision ultimately would be up to DNR.

Bennett Hospitality officials did not respond to a message left with staff asking for comment.

When asked what happened to the sign, which had a town of Mount Pleasant logo, town administrator Eric DeMoura, said no one knows.

“It was likely taken, which happens from time to time,” he said, adding the town will replace it. 

Protecting significant tracts like the Patriots Point site has become a priority for birds conservation groups as the decline of everyday species becomes more pronounced and more previously open habitat is lost.

Nearly 3 billion fewer birds fly in the United States than did 40 years ago, researchers at the benchmark Cornell University Ornithology Lab said in a recent report. The worst losses have been among common “backyard” birds — blackbirds, sparrows, warblers.

Nearly two-thirds of the bird species seen every day in places across the nation could be lost by the end of the century — an estimated 389 species — as the climate continues to warm, Audubon South Carolina reported in October.

In South Carolina, the projected loss figure is 20 percent or as many as 50 birds.

The Patriots Point woods were torn up significantly by Hurricane Matthew in 2016 and ensuing storms but still serves as an oasis for warblers, thrushes, vireos and other birds, said Matt Johnson, Audubon’s state director of bird conservation and engagement.

“Given its location on the edge of Charleston Harbor, this small piece of property is really important for birds, especially those that are migrating through in the fall,” he said.