Inlets are pathways, created by natural or anthropogenic processes, which allow for sea water to enter the back barrier systems of a coastline. These openings provide a valuable pathway to the sea. Not only are they used by commercial and recreational fisherman, they also provide a mechanism for larvae of many different species to enter the nursery habitat provided in the protective estuaries.      The term inlet is actually somewhat of a misnomer has most actually release larger volumes of water than they take in, making outlet a more appropriate term. Several significant features also occur as a result of inlet formation. Large flood tidal delta lobes may form on the landward side of the inlet due to the large amount of sediment brought in by the flooding tide. Seaward of the inlet, ebb tidal lobes are found, which also form due to sediment resuspension by the falling tide. These features are usually smaller than the flood tidal lobes due to differences in velocity.      Jetties are hard structures used to create a permanent opening for a given channel. This is accomplished by building long stone walls, which protrude several hundred meters out into the ocean and interrupt the natural transportation of sand. This interruption causes sand to pile up on one side of the jetty and actually accelerates erosional processes on the other. These features also have detrimental affects on the wildlife of the area, limiting larval transport and overall access to the estuary. One solution to this problem is the implementation of weir sections within the jetty, which allow organisms floating on the surface of the water to pass over a lower section of the stone structure.      Shown below is an aerial photo of Sebastian Inlet in Florida, which shows flood and ebb tidal features, as well as a jetty system. Delineation of hydrographic regions