Lesson learned from Fig Island

During the time of the earliest pyramids, American Indians began piling oyster shells at Fig Island.

In just a few years they feasted on more than a billion oysters from the waters around the 20-acre hummock near Wadmalaw Island.

They built up shell rings high enough that fires on it could be spotted from shell rings about 10 miles to the north and south, and created an arena large and intricate enough that archaeologists still puzzle over what it was all about.

Then the Indians died out abruptly.

They left enough shells to fill a stadium full of Olympic-size swimming pools, enough shells that, if they were living oysters, would filter contaminants from a body of water the size of Copahee Sound between Mount Pleasant and Dewees Island.

They might have eaten themselves out of house and clean water habitat, exacerbated by a rapid rise or fall of sea level.

"Ecologically speaking, they built a more complex system than was on the coast before they arrived, and they concentrated it.

"The lesson to learn here is it doesn't take long to wipe that kind of system out," said Richard Dame, Coastal Carolina University marine science professor emeritus, who has studied the site.

"The thing is, if you run out of food, you die. Everybody can have good intentions. But these coastal systems are complex, and they are not always predictable."

Reach Bo Petersen at bpetersen@postandcourier.com or 745-5852.