Field evaluation of aerial applications of hydramethylnon and metaflumizone to control the red imported fire ant, Solenopsis invicta (Buren) and related ant species (Hymenoptera: formicidae)

摘要

The red imported fire ant (RIFA) was introduced to the United States from SouthAmerica over 75 years ago, and has become a pest in wildlife settings. Hydramethylnonfire ant bait has been the industry standard for controlling the red imported fire ant. It canbe compared to novel baits, and used to evaluate different aerial application techniques,such as the "skip swath" method. Two baits, hydramethylnon and metaflumizone, and askipped-swath method were evaluated through observations of the activity levels of RIFAmounds and abundance. The effects of RIFA on other ant species were determined byeliminating RIFA with insecticides, and then sampling for all remaining ant species.Measurements of RIFA mound activity was done by recording their response to thevibration of wire flags located in active mounds. This method indicated control of RIFAwith hydramethylnon and metaflumizone from 61 to 180 d post-treatment. Additionalmonitoring for RIFA activity, in the same plots, was done with baited vials. These resultsindicated that complete control of RIFA was never achieved with either hydramethylnonor metaflumizone within 180 d post-treatment; however, there were significant reductionsin RIFA population as a result of both chemical baits from 3-92 d post-treatment. A reduction of RIFA populations occurred with both baits, as determined through scheduledsampling of all ant species using baited vials. Native ants, such as Dorymyrmex spp.,were found in higher numbers once RIFA populations were reduced, indicating that thetwo ant species compete for resources such as food and space. Dorymyrmex spp.numbers were suppressed by RIFA populations, while other ants, such as Paratrechinaspp. were unaffected.