Oyster reef
Members of Team MacDill and Tampa Bay Watch work together to build up an oyster reef along MacDill Air Force Base, Fla.’s shoreline Oct. 17, 2013. The reef, made of mesh bags filled with fossilized shells, helps to prevent erosion by trapping sediment once it has passed over the reef and provides a habitat for some sea life. (U.S. Air Force photo by Airman 1st Class Sarah Hall-Kirchner/Released)