The importance of soil on incipient colony development of the Formosan subterranean termite

In termites, a pair of reproductives (queen and king) start a colony after their dispersal flight. During this colony foundation period, it was suggested that the initial weight of reproductives is a critical factor for colony foundation success. However, there might be another factors that could affect incipient colony development such as initial habitats of the colony. In this study, we investigated the effect of soil on incipient colony development of Coptotermes formosanus Shiraki. A pair of reproductives was introduced into a vial containing either four pieces of wood (hereafter wood) with nitrogen-rich organic soil or wood without soil conditions. Rearing units were kept for six months without any disturbances. We measured colony growth parameters such as total biomass, number of termites and the weight of reproductives at zero, six and twelve months. In general, total biomass and the number of termites were significantly higher in colonies reared in the wood with organic soil environment than colonies reared in other environments. The initial weight of reproductives and total biomass gains were positively correlated when organic soil was present and not significantly correlated in both wood with sand and wood only environments. In addition, both reproductives from colonies reared in the wood with organic soil environment lost significantly less weight than reproductives reared in the other environment.