Natural dune systems used to extend the length of Pinellas County's barrier islands. However, the primary dunes, which under natural conditions provide sand to the beaches, have been covered or destroyed along much of Pinellas County's barrier islands. Now, natural primary dunes of significance are found only on Caladesi Island, north Clearwater Beach and portions of Treasure Island, Long Key and Mullet Key.
Artificial dunes have been created on Clearwater Beach, on the northern portion of Sand Key, throughout Treasure Island, on the southern tip of Long Key and in Madeira Beach.
Recognizing the value of dunes in the protection of property and the maintenance of the beach, many of the municipalities, homeowners and business owners along the beaches have organized and participated in sea oat plantings to help build dunes. Their efforts are paying off with a dune system being re-established along many areas on the coast.