Dog Island is a slightly developed barrier island south of Carabelle, Florida in the northeast Gulf of Mexico. Five sedimentary facies were identified in eighteen vibracores recovered from Dog Island. Data from the cores support the theory that the Apalachicola barrier islands have evolved though shoal aggradation and beach ridge progradation. Radiocarbon dates indicate that the island is 3,000+ or -1000 years old. It is composed of sediments deposited by the Apalachicola River and reworked by the Holocene transgression. Numerous beach ridge sets show a complex history of island growth and erosion. An apparently cyclic pattern of straight and recurved beach ridges provide a history of alternating modes of sediment transport. Large scale, periodic, catastrophic weather events followed by island recovery and sediment redistribution can explain these patterns. Trends seen from less severe storms during historic times seem to mimic this pattern on a smaller scale. Exhumed peat beds and tree stumps on the Gulf side of the island attest to the large scale recession of the shoreline shown in historic maps. Sediment budgets demonstrate that erosion rates on Dog Island have oscillated about a narrow range increasing slightly over the last 150 years. The effects of storms and seasonal weather patterns are magnified in short-term studies, but on longer time scales their effect is negligible. A slowly increasing rate of erosion on the Gulf side of the island with deposition on both ends has persisted over the last 150 years resulting in Gulf shoreline retreat of up to 300 m and lateral progradation of approximately 500 m on each end.