Impact of area-wide management on alate densities of the Formosan subterranean termite (Isoptera: Rhinotermitidae)

Abstract:
An area-wide management project to control the Formosan subterranean termite, Coptotermes formosanus Shiraki (FST), in the New Orleans French Quarter (FQ) began in1998. Initially, all properties within fifteen square blocks were treated with either commercially available non-repellent termiticides or baits. Application was by commercial applicators through state approved pest control contracts. The treatment area has been expanded twice since inception of the project, once in March 2002 and again in March 2004. Each area is labeled respectively according to the date treatment began. Thus, Area I is the original 15 blocks; Area II is the first expansion; Area III is the second expansion; Area IV is the area on the levee and Area V is the untreated blocks. To monitor the termite densities alate traps were installed throughout the entire FQ. The alate traps were monitored at least twice weekly during the alate swarming season from April 1 to July 30. Alate trapping across all areas since 1998 indicates that Area III and the northeast most part of Area V have been the most densely infested areas in the FQ. Area-wide treatment in Areas I and II resulted in at least a 50% decline each in the number of trapped alates two years after area-wide treatment began. Although the number of trapped alates in Area I has been consistently lower than the number trapped from the surrounding areas (In 2004, for example, Area I, X = 278 vs. Area III, X = 1023), the average number of alates captured in Area I has remained unchanged since the initial decline in 2000. The continuing presence of alates in Area I is attributed to above-ground infestations in the treated structures and to infestations in secondary untreated structures (e.g. storage sheds), untreated common walls, trees and debris buried in the area. Inspection of trees and all structures, followed by treatment when active termites were discovered was begun in October 2003 to further reduce the persistent FST infestations in the managed areas.