Applying UAS Photogrammetry to Analyze Spatial Patterns of Indigenous Settlement Sites in the Northern Dominican Republic

Abstract

When in December 15, 1492 Christopher Columbus' ships passed the hilly north of an island he had named La Hispaniola, today divided into Haiti and the Dominican Republic, he noted in his captain's log smoke of many fires rising from the hill tops. While it remains questionable if these were meant as signals or simply represented daily domestic activities, his description provides evidence of indigenous occupation on the slopes of the island's northern mountain ranges. What evidence can be found through photogrammetrically surveying pre-colonial settlements in northern Hispaniola? Archaeological topographic studies show that the first inhabitants of this island significantly transformed the landscapes they lived in---these `footprints' now serving as one of the criteria that indicate an archaeological habitation site. The indigenous settlements were located on hill tops, flanks, slopes or ridges, their settings provided a view over a valley or towards the sea, and good inter-visibility between various settlements. Depending on the location, the intra-site topography can either be characterized as a group of shallow mounds (i.e. montículos described by the Spanish) or flattened areas, each of which having been dug into the natural slope to level the base for wood-supported round houses---Excavations of post hole features in a circular array in the north-western Dominican Republic support this theory. Around these house structures ceramic, lithic and food waste was dumped creating shallow mounds, which were additionally used for other domestic and ritual purposes. The recent development of affordable, small, camera-mounted UAS, has made it possible to record these sites by photogrammetric means. The resulting orthophotos and the DEM analysis complement the archaeological finds of the site of El Manantial in the Montecristi province. They highlight the slight changes in soil patterns and topography, and reveal the existence of levelled mounds. The technique shows great potential for fast and precise recording of archaeological sites in difficult terrain. Digital reconstruction could provide answers how a village was spatially structured and organized at its time of occupation. In addition, the technique provides an opportunity to map and measure more recent changes to the landscape, caused by excavations, illegal looting or ploughing.