"I don't think there is a more dynamic big piece of real estate on the face of the earth," says Pilkey, director of Program for the Study of Developed Shorelines at Duke. "That's not just the shoreline moving, that's the whole island."
People have tried to anchor the islands with sandbags, seawalls and beach nourishment via sand dredging and dumping. In many regions of Florida, Georgia and South Carolina, the original beaches have gonereplaced by sand pumped in by beach-nourishment programs.
The United States has 405 barrier islands adding 3,054 miles (4,900 kilometers) of additional beachesnearly one quarter of the world's total barrier island mileage. Mexico follows in second place with 104 islands measuring 1,392 miles (2,240 kilometers). Russia takes third with 226 islands measuring 1,020 miles (1,640 kilometers).
"In the long term, we can't hold islands in place," Pilkey says. "We have to decide which is more important: buildings or beaches? The problem in North America is basically at its peak because almost all the beachfront property that could be developed has been sold by now."
The development issues are worldwide. "Taiwan, for example, is an end point if ever there was one," Fraser says. In 1945, Taiwan had 35 barrier islandsnow there are five. The Taiwanese filled in the lagoons between the mainland and the island and built massive sea walls to hold everything in place.
Fraser and Pilkey appreciate the inherent fragility of her subjects.
"We've got to live with the islands, not just on the islands," Pilkey says. "Living with the islands means allowing them to evolve as they would naturallyeven though we are on that island."
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