Ancient engineering of fish capture and storage in southwest Florida

Significance Fish were captured and stored by Native Americans of southwestern Florida in complex walled structures called watercourts, constructed of shell and other sediments. These structures were engineered with knowledge of tidal systems, hydrology, and the biology of species to be stored in these courts. This work documents the considerable ability of the Calusa, a nonagricultural society, to engineer systems that significantly alter their natural environment. These structures are associated with an ever-growing population and complex system of governance among the Calusa of Florida. In the 16th century, the Calusa, a fisher-gatherer-hunter society, were the most politically complex polity in Florida, and the archaeological site of Mound Key was their capital. Based on historic documents, the ruling elite at Mound Key controlled surplus production and distribution. The question remains exactly how such surplus pooling occurred and when such traditions were elaborated on and reflected in the built environment. Our work focuses on the “watercourts” and associated areas at Mound Key. These subrectangular constructions of shell and other sediments around centralized inundated areas have been variously interpreted. Here, we detail when these enclosures were constructed and their engineering and function. We argue that these structures were for large surplus capture and storage of aquatic resources that were controlled and managed by corporate groups.