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Crane beach represents a very complex site in terms of coastal processes and sand transport in particular. As a result of bi-directional waves there is a convergence of sand transport at the location of the existing headland for much of the time, at least along the beach and in shallower water. These conclusions are based on a combination of interpretation of field data, shoreline change data and numerical and physical modeling.

The unique orientation of Crane Beach South (facing more to the SE than most beaches along this shore) is directly linked to the level of protection provided by Cobblers Reef. Specifically, significant wave energy radiates through a gap in Cobblers Reef located to the SE of the beach (offshore of the Crane hotel headland), while much less wave energy propogates across the higher crested reef directly offshore of the headland between the north and south beaches. This process has been demonstrated through numerical model simulations of nearshore wave transformation.

Despite some evidence for tremendous loss in beach width historically, there is no clear evidence that there is a long-term erosion trend (i.e. since Hurricane Janet in 1955). The one possible exception is the condition of the beach adjacent to and north of the revetment protecting the private property at the north end of Crane Beach South, where Halcrow (1999a) reports a recent and ongoing reduction in beach width making beach access difficult and hazardous.

Any ongoing and future long-term erosion will be due to a negative balance between sediment lost offshore and sand supplied by reef production. It is possible that sand supplied by Cobblers Reef may be reduced in the future, increasing the potential for higher long-term erosion rates.