Selecting ant baits for an IPM strategy for Caribbean crazy ants, Nylanderia pubens (Forel) based on macronutrient preferences and nest demographics

ABSTRACT. The Caribbean crazy ant (CCA), Nylanderia pubens (Forel) is an invasive urban pest with enormous populations that infests homes and lawns in the southeastern United States. Standard pest management practices are ineffectual as perimeter spray applications suppress ants for only a few weeks. Insecticide baits, when used in conjunction with standard IPM practices, may provide acceptable suppression of CCA populations. Ant baits must be attractive, palatable, efficacious and used when ants are actively foraging. The objectives of this study are 1) to determine the macronutrient preferences of CCA over an annual cycle, 2) evaluate the attractiveness and efficacy of commercially available baits and 3) study nest demography to determine optimal bait application timing. In macronutrient choice tests conducted at four sites in Florida, it was determined that overall dietary preference of CCA is for proteinaceous foods, but there is a shift to carbohydrates in the fall. Laboratory bioassays of bait attractiveness and efficacy of 15 commercially available ant baits against CCA were conducted over three seasons. Amdro Pro and Maxforce Complete and were significantly different from all other baits tested with regard to percentage of ant mortality at 3 DAT and  100% mortality in the fewest days. Nest demography studies revealed that the period of highest brood production occurs in the spring, correlating with increased protein demands during this time. In conclusion, an IPM strategy for CCA should include protein based baits in the spring and summer when ants are actively foraging and experiencing increased colony growth.