Molting site fidelity: A case of death chase in Coptotermes formosanus (Isoptera: Rhinotermitidae) colonies treated with chitin synthesis inhibitor baits

Site fidelity by molting termites in Coptotermes formosanus colonies is a new addition to our understanding of lower termites’ behavior and biology. In our studies, workers in the colonies traveled from foraging sites to the central nest and molted in the proximity of eggs and reproductives. Although molting is an important issue when attempting to eliminate a subterranean termite colony using molt disrupters like chitin synthesis inhibitors (CSIs), our knowledge on spatial distribution of molting individuals that die under the effect of CSI in a colony is limited. Here we report the spread of death and response of the surviving individuals including reproductives to dead individuals in a colony. The aversion to the dead and decaying individuals causes physogastric queen to leave the original inhabited site in a colony and refuge at newer site every few days. Because mortality was an event observed only in the individuals undergoing molting under the effect of CSI, death was observed only around reproductives in the form of molting individuals with molting site fidelity. In the final few days of senescence of CSI baited colony, some reproductives were spotted in the bait chamber; which agreed with field observations.