It's even more encouraging to see plants colonizing and stabilizing the fresh sand. The vegetation will help maintain the sand through wind and rain, so that the growth of the dunes is permanent. Eventually as organic matter filters down through the sand it will take on the appearance of soil. In several places this friable soil is exposed due to dune erosion. When the sand that once formed an energy absorbing barrier is removed, the soil is unprotected and vulnerable.
Gaps form in the barrier.
The force of the waves during especially high tides carries sand inland, and further undermines the crumbly soil. When this occurs, there is no longer a barrier for the sand to bank up against, and the erosion cycle continues. There are several pieces of old ironmongery, two car wrecks and several wartime concrete constructions, around the beach. These are probably not helping the impression of Maui as an unspoiled paradise, but they are remnants of Maui's history. We can only guess at their effects on the reef and wildlife.