| Summary: | The geomorphology of tropical island beaches has received little attention in literature compared to their temperate equivalents. This is particularly true of studies of the spatial and temporal variability of carbonate beaches. The British Virgin Islands (BVI), a small archipelago located in the north-eastern Caribbean contains numerous beaches in a wide variety of settings within a small geographical area. Over 100 beaches across 60+ high volcanic and reef islands were selected for study. Through the analysis of benthic habitat maps, aerial photographs, sedimentary characteristics, and ground-truthing, beach distribution and form are interpreted in terms of their geologic, oceanographic and ecologic setting. The Atlantic-facing beaches exhibit modally high energy waves which drive carbonate-rich sediment onshore from extensive reef systems and a carbonate bank. In contrast, Caribbean-facing beaches, primarily those of coral rubble, are dominated by modally low energy waves punctuated by very high energy events (i.e. hurricanes) and contain a lower proportion of fine-grained carbonate sands. While some of these high energy events have significant short-term impact, many beaches exhibit long-term stability. There has, however, been a general narrowing of beaches over the past 50 years which is tentatively attributed to sand mining in the past. In contrast to the high volcanic islands, Anegada is an emergent reef island comprising a lithified Pleistocene reef core and a sequence of Holocene deposits (beach ridges, lagoons, and mangroves). The form and distribution of the island's contemporary sedimentary environment reveal four distinctive coastlines. Three of these coastlines have shown relative stability over the past 149 years while one coastline has morphologically adjusted to surrounding environmental conditions by rotating in a counter clockwise motion. All the beaches are subject to a variety of human impacts and require a formal coastal management response, however, this has not yet been realised. Despite an existing statutory framework for beach management, environmental degradation from uncontrolled coastal development and space-use conflicts caused by unmanaged mass tourism continues. A current case study reveals the management plan requires implementation via a co-management regime between the local beach community and stakeholders with support from the local government. A simple framework is presented that provides thirteen environmental, socio-cultural, economic and governance goals which define the context in which the management plan operates. This framework ensures not only a clear understanding of what constitutes sustainable beach management, but also sustainable development specifically within the BVI.
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