AN ASSESSSMENT OF SHORELINE CHANGE FOR SMALL ASSOCIATED ISLANDS OF PUERTO RICO AND THE UNITED STATES VIRGIN ISLANDS
Maximum erosion measured for a single transect was 132.35 meters, the maximum accretion for a single transect was 69.42 meters. The overall mean change was -4.7 meters, and the overall mean rate of change was -0.12 m/yr. Within individual islands, the greatest shoreline change rate is -0.83 meters/year, exhibited by Cayo Ratones. Many of the islands are very nearly stable. Cayo Ratón. Cayo Santiago, Isla Magueyes, and Isla de Cardona exhibit accretion. While erosion is dominant on the island shorelines, it is not a rapid rate of change. And in fact, the mean shoreline change rate on all but five of the islands is within the statistical margin of error of +/- 0.2 m/yr. The largest percentage of an island’s shoreline exhibiting erosion is 95%, found on Cayo Ratones, Isla de los Palomas, and Isla Morrillito. Measurements reveal a total area of land loss for all 20 islands of 20.32 hectares (50.2 acres).