# The Impact of Termiticides on Termite Corpse Management

## TL;DR

This study investigates how termiticides affect the behavior of termites toward dead nestmates, revealing that chemical changes in corpses don't always alter their behavior.

## Contribution

The study reveals that termiticides alter corpse volatiles but do not consistently change termite behaviors like corpse removal.

## Key findings

- Termiticides like bifenthrin and fipronil alter corpse volatiles such as 3-octanol and 3-octanone.
- Despite chemical changes, termite behaviors like corpse removal remain largely unchanged.
- Bifenthrin is an exception, showing some behavioral differences in corpse management.

## Abstract

This study explores how chemical treatments for controlling termites affect the behavior of surviving termites toward their deceased nestmates. Focusing on the eastern subterranean termite, Reticulitermes flavipes, it examines the effects of two primary termite control methods: soil treatments and baits. The overall goal of this research is to clarify how these treatments impact the volatile profile of termite corpses and subsequent behaviors of living termites. Significant differences in volatiles, such as 3-octanol and 3-octanone, were detected in corpses resulting from exposures to the termiticides bifenthrin and fipronil. These chemical changes, however, did not consistently alter behaviors such as corpse removal or cannibalism, suggesting a complex interplay between chemical signals and termite behavior. Apart from bifenthrin, behavioral responses showed no significant differences across treatments. These findings suggest that while postmortem chemicals do influence behavior, they do not solely dictate how termites interact with their dead nestmates. These combined results underscore the importance of understanding termite undertaking behavior to improve pest management strategies, paving the way for more effective and environmentally sustainable control practices.

Soil treatments and baits are two primary chemical control strategies for subterranean termites. Baiting is targeted and eco-friendly but requires ongoing maintenance, while soil treatments provide immediate, long-lasting protection with potential environmental concerns. Previously, we found that termites differentially manage deceased individuals based on their postmortem chemical signatures, potentially circumventing chemical controls. Given the distinct differences in the synthetic termiticides used for soil treatments (fast-acting) and baits (slow-releasing), we hypothesized that termites would respond differently to corpses treated with these two methods. To test this hypothesis, in Reticulitermes flavipes, we (1) profiled postmortem chemicals in termites exposed to different termiticides and (2) documented live termite responses to these corpses. Significant variations in postmortem chemical signatures, particularly 3-octanol and 3-octanone, were found among termites exposed to different termiticides, especially bifenthrin and fipronil. However, these variations did not lead to significantly different undertaking behaviors, indicating a complex relationship between death cues and termite behavior. Contrary to our hypothesis, except for bifenthrin, the fundamental undertaking behaviors were consistent despite differences in retrieval timing. This suggests that termiticides alone do not fully dictate termite undertaking behavior. Understanding termite corpse management is crucial for evaluating termiticide effectiveness, highlighting the need for an integrated pest management approach.