Research Articles

A two-step management strategy was evaluated for rapid feeding suppression and colony elimination of termites (Reticulitermes speratus) infesting wooden cultural heritage structures (WCHS). A large-scale (15-m foraging distance) arena system with a colony size of 10,000 termites — consisting of a main nest, a shelter, and fipronil-treated wood units connected by foraging tunnels — was utilized to compare an untreated control group, a fipronil-treated group, a bistrifluron-treated group, and a combined treatment (F+B) group. In the fipronil-treated group, feeding on the treated wood rapidly decreased, demonstrating rapid reduction in wood consumption on treated wood; however, colony survival persisted and feeding activity was redistributed toward the untreated shelter zone. In contrast, the bistrifluron-treated group ultimately achieved complete colony collapse, although feeding on both the treated wood and shelter wood continued during the elimination process. The combined treatment rapidly suppressed feeding on the treated wood and completely eliminated the colony within 10 weeks through subsequent bait consumption. Furthermore, the combined treatment significantly reduced the feeding redistribution toward untreated wood sources that were observed in the fipronil-only group. These findings suggest that the combined application of fipronil-treated wood and CSI bait can provide both immediate protection for WCHS members and long-term colony elimination, offering a promising approach that warrants further field validation as an efficient termite management strategy for WCHS.