Answer:
These islands are barrier islands.
Explanation:
Barrier islands are islands in front of the mainland that separate part of the sea from the open sea. They lie parallel to the coast and have an elongated, narrow shape. On the sea side, dunes often shape the surface, on the land side they are flat. They were created by deposits of waves, currents and wind. Their formation requires a shallow coastal fore, a sufficiently large sediment store and a weak to moderate tidal range.
