In the early modern era, the hinterland of a Caribbean island encompassed more than the land sequestered by its sandy shorelines. This article uses the loggers of Barbados and the turtlers of Jamaica to explore how Caribbean colonists forged and maintained maritime hinterlands in order to supply island residents and feed urban populations. In timbering nearby islands and harvesting adjacent waterscapes, loggers and turtlers forged an interisland web of ecological and economic relationships that inextricably linked proximate islands to one another. Barbadians, for example, depended on timber from St. Lucia, and Jamaicans provisioned Port Royal with turtles from the Cayman Islands. In both instances, colonists and local officials claimed these nearby islands as “dependencies” of the larger colony and sought to defend them. By reorienting our understanding of hinterlands from interior lands to neighboring islands and seascapes, this article offers a new way of thinking about port cities, sufficiency, and industry, especially in plantation America. Rather than peripheral trades with little economic value, ventures such as timbering and turtling promoted vernacular industries, which in turn reduced reliance on imported goods, thereby enabling the islands of Barbados and Jamaica to become efficient, populous colonies within a profitable Atlantic empire.