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ABSTRACT Alluaud's little yellow ant,Plagiolepis alluaudiEmery 1894, (Hymenoptera: Formicidae), is an emerging nuisance species in floriculture and residential areas around the globe. Originally described from Madagascar, it ranks among the smallest widespread formicine pests. To date, no evaluations of management protocols for this species have been reported. In ants, feeding preference is related to ant body size and viscosity and nutritional content of the food source. Optimizing these factors could lead to improved bait performance. To assess population management implications of various bait parameters on a small pest ant species, four commercial ant baits of varying viscosities, active ingredient (AI) group and concentration, and nutritional content were evaluated in laboratory and field assays againstP. alluaudi. All four products negatively affectedP. alluaudisurvival compared to the untreated control, and all products were associated with greater visitation compared to the control, suggesting all AIs tested are viable candidates forP. alluaudimanagement. However, their direct use for population management in the field may be limited, as feeding cessation was eventually observed on all four baits. When baits were diluted with water, viscosity was reduced and survival was initially higher compared to with undiluted baits. However, similarly low levels of survival were maintained over time. Most importantly, we found in a 2‐year observational field study involving sustained baiting within an infested structure that only the bait formulation with the lowest overall viscosity was able to alleviateP. alluaudinuisance indoors. Our results suggest that diluting baits may be a viable strategy for targeting very small pest ant species, and the greater time to lethality of diluted baits, resulting from reduced toxicant concentration, may be a reasonable trade‐off allowing smaller ant species to continue feeding for a sufficient duration on a bait formulation.
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Are ants botanists? Ant associative learning of plant chemicals mediates foraging for carbohydrates
Abstract 1. Although associative learning is widespread across animals, its ecological importance is difficult to assess because learning is rarely studied in the field, where informative cues are juxtaposed against complex backgrounds of uninformative noise. 2. Ants rely heavily on chemical cues for foraging and engage in many ecologically important interactions with plants. Nevertheless, little is known about the role of associative learning of plant chemicals in ant foraging for carbohydrates. 3. In a field setting, the present study investigated whether the distantly related ant speciesFormica podzolica(Formicinae subfamily) andTapinoma sessile(Dolichoderinae subfamily) exhibited associative learning of the chemical cues from two co‐occurring plant species that are taxonomically and chemically distinct (Asteraceae:Helianthella quinquenervisand Apiaceae:Ligusticum porteri). 4. For two consecutive summers, ants were trained to forage from artificial sugar‐rich baits associated with the leaf chemicals from eitherH. quinquenervisorL. porterifor 24 h, after which a two‐choice test was deployed to assess whether ants would be more likely to select baits associated with the same (versus different) plant chemicals on which they had been trained. 5. The present study demonstrates associative learning of chemicals from both plant species, and these effects were consistent between ant species and years; training increased bait occupancy from 42% on the untrained scent to 66% on the trained scent. These results indicate that associative odour‐learning may be widespread across ants and serve as an important mechanism mediating ant selection of resources.
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- Award ID(s):
- 1755522
- PAR ID:
- 10458310
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ecological Entomology
- Volume:
- 45
- Issue:
- 2
- ISSN:
- 0307-6946
- Format(s):
- Medium: X Size: p. 251-258
- Size(s):
- p. 251-258
- Sponsoring Org:
- National Science Foundation
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