This island will cease to exist. That much seems certain. Over the last six decades, more than 98% of Isle de Jean Charles has vanished into the Gulf of Mexico, leaving a frail strip of land just two miles long and a quarter-mile wide. With each high tide and with each hurricane, a little more of this historic Native American land sinks below the surface. Cow pastures are gone. Rice fields are gone. The encroaching saltwater seeps into the roots of the towering live oaks that loom over the bayou, transforming them into eerie gray skeletons.