The archaeological signature of ‘ant bed’ mound floors in the northern tropics of Australia: case study on the Lower Laura (Boralga) Native Mounted Police Camp, Cape York Peninsula

Ant bed (also known as termite mound) floors were a common feature of historical buildings in colonial Australia, yet they are rarely identified in archaeological contexts. In this paper we present a case study of these features in buildings associated with a late nineteenth century Native Mounted Police camp in Cape York Peninsula, Queensland. Aboriginal colleagues reported the former existence of these floors in buildings at the site, though none could be seen at the contemporary ground surface. The question thus existed as to whether they were extant in subsurface contexts. Ground-penetrating radar revealed rectangular, high amplitude reflections in many parts of the site. Excavation demonstrated these features comprised stratigraphically discrete units that were highly compact, often with a substantial gravel component. Sediment analysis of the coarse-grained component has distinguished these floors from surrounding off-site samples. The level of compaction seen in the floors has significant implications for the retrieval of artefacts in such contexts since it prevents any objects from being integrated into the deposit. While the distribution of the practice of using ant beds for floors is unknown, it appears their use was common throughout Australia in the late 18th through the 19th and 20th centuries. Examination of the physical elements that make up these floors has provided a clearer idea of each floor's recorded history and use. We have also identified a methodology for examining ant bed floors in Australia and elsewhere that can be used anywhere that ant mounds occur and may have been a source of flooring material.