Foraging Populations and Control Strategies of Subterranean Termites in the Urban Environment, with Special Reference to Baiting

This paper reviews the literature on foraging populations, and control of subterranean termites with special reference to baiting. Studies on foraging populations of subterranean termites generally involved population characterization and estimation of foraging territories. Population characterization was normally conducted using mark-recapture techniques (single or triple) by trapping subterranean termites in underground monitoring stations, followed by marking the insects using histological dyes. Methods of studying foraging territories of subterranean termites involved the use of radio isotopes, direct excavation, histological dyes, flourescent paints and conducting agonistic behavioral experiments. Subterranean termite control strategies included chemical, biological and physical control methods. The soil treatment and baiting methods were common chemical methods, while the use of specific sand or granite particles, and stainless steel mesh are recent advances in physical exclusion method. Baiting is a relatively popular method which takes the advantage of social nature and foraging behaviour of subterranean termites where food sharing among the workers and nestmates through trophallaxis could enable the transfer of slow-acting toxicant to the whole colony. Many potential active ingredients as bait toxicants had been evaluated including metabolic inhibitors, fungi (bioagents) and insect growth regulators (IGRs), but only the latter has been