This dataset, prepared by the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center, provides first and last return elevation data collected during a September 20-22, 2006 airborne lidar survey for the Chandeleur Islands, Louisiana, and Cat Island, Mississippi, through Dauphin Island, Alabama. Elevation measurements were collected over the area using the National Aeronautics and Space Administration (NASA) Experimental Advanced Airborne Research Lidar (EAARL), a pulsed laser ranging system mounted onboard an aircraft to measure ground elevation, vegetation canopy, and coastal topography.