An aerial view of Tangier Island looking south just after sunrise as rain showers pass the island. Shore erosion from the Chesapeake Bay is thought to be a major threat to the island. (Timothy C. Wright/For the Washington Post)

Five months after President Trump lent his support to the mayor of a tiny island with a vanishing shoreline, Virginia's senators are urging the president to protect Tangier Island from disappearing into the Chesapeake Bay.

Democratic Sens. Mark R. Warner and Tim Kaine, both former governors who have visited Tangier, sent a letter to the White House asking Trump to fulfill his promise to the island's mayor, James "Ooker" Eskridge.

In the summer, Trump called Eskridge, whose constituents are overwhelmingly Republican, and said his island of mostly watermen and their families would remain intact. The pledge came despite reports that show that Tangier could be uninhabitable in 25 to 50 years.

Many island residents disagree that man-made climate change is to blame and say natural erosion washing away land has finally come to their doorsteps. In their letter, Warner and Kaine avoided the reason Tangier is disappearing at an average rate of eight acres a year.

"We can debate the causes for why this is happening, but regardless, the effects are clear," they wrote. "It is urgent that we address those effects."

They suggested that Trump expedite an Army Corps of Engineers study of Tangier's infrastructure needs, consider a proposal to use soil from dredging projects to build up the island, and direct the U.S. Fish and Wildlife Service to manage part of the island.

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The 1.2-square-mile island off the Eastern Shore, with its 460 residents, may not score well on traditional federal cost-benefit analyses, but the senators asked Trump to consider Tangier's other assets.

"Its history and culture predate the United States, and its linguistic characteristics are unlike any in the world," they wrote. "Letting this island wither away due to bureaucratic inertia — or worse, an active decision to write it off — would not only result in the loss of people's homes and way of life, but would be a cultural and historical loss to America."