Dunes, eolian ripples and wind shadow structures characterise the topographically higher regions of Sagar Island and Lower Sands - the two tidal islands. The dunes have formed under conditions of high humidity and moderate to high rainfall in wet, cohesive sand under the influence of a dominant southerly wind. Halophytic herbs and shrubs have great control over their formations. The internal cross-laminations of these dunes show a higher angle of dip than those of the desert dunes. -from Authors