Seasonal Variation in Bait Attractiveness Among Six Mediterranean Pest Ant Species: Implications for Toxic Bait Development

Toxic baits are central to professional ant management, but their efficacy depends on matching macronutrient composition to target species’ preferences, which may vary within species and season. Comparative data across co-occurring Mediterranean ant pests are scarce. We quantified protein, carbohydrate, and mixed-diet preferences in six Mediterranean ant pests—Crematogaster scutellaris, Pheidole pallidula, Tapinoma darioi, Linepithema humile, Lasius neglectus, and Lasius grandis—using 10 replicates per species and season across autumn and spring. Distinct patterns of bait attractiveness were observed among the six studied ant species. Crematogaster scutellaris, P. pallidula, and T. darioi favored protein, whereas invasive L. humile and L. neglectus preferred carbohydrates. Lasius grandis showed no clear preference. Seasonal shifts occurred in some species: P. pallidula and L. neglectus increased protein recruitment in spring, L. grandis favored mixed diets, and L. humile shifted further toward carbohydrates. Thus, carbohydrate-rich matrices are indicated for invasive L. humile and L. neglectus, whereas protein-biased baits suit C. scutellaris, P. pallidula, and T. darioi. Seasonal adjustments, such as increased protein in spring for P. pallidula, may enhance bait attractiveness. These findings provide a species-resolved nutritional framework to guide the development of targeted, season-adapted bait formulations for Mediterranean ant pest management.