Elucidating the trophic role of Tapinoma ibericum (Hymenoptera: Formicidae) as a potential predator of olive pests

Abstract

Ants play a key role in improving the structure and function of local communities. They interact with plants, herbivores, predators and parasitoids and are able to change their trophic role in space and time. These features, however, make it difficult to establish the net trophic role of ants in agroecosystems. Here we aim to determine the isotopic enrichment and tissue incorporation rates in ants of the Tapinoma nigerrimum complex, which are found abundantly in olive orchards (i.e. T. ibericum), to determine their trophic role through stable isotopes analysis. We compared the isotopic signature of ants feeding on (1) natural diets, (2) experimental diets and (3) contrasting diets of ants inhabiting natural habitats and olive orchards with different management systems. Then, we contrasted our isotopic results on natural diets with the prey of ant foragers in olive orchards. Our results showed that (1) ants from olive orchards had an isotopic signature different from that of a hyper‐predator; (2) the isotopic signature did not vary significantly amongst different management practices and (3) the diet of ants in nature varies greatly on preys according to resource availability, which may be reflected in isotopic signatures. Therefore, T. ibericum is a species that can potentially contribute to control olive pests without posing a risk to other natural enemies because commonly it is not a hyper‐predator. The information presented here could be used by farmers and technicians to enhance local biological control planning and/or strategies in olive orchards.

Ant Community Is Not Influenced by the Addition of Olive Mill Pomace Compost in Two Different Olive Crop Managements

“…(in both groves again), although in the canopy of the traditional grove other species appear secondarily (P. pallidula and T. nigerrimun), but in very low quantities. Several works tend to give T. nigerrimum (and other Tapinoma) an important role in the predation of P. oleae larvae (an important pest in olives) in the canopy [35][36][37]46], but the very low presence of this species in the canopy survey of this work does not seem to support a significant role as a predator in both groves, where the presence of P. oleae was very low in spring (when anthophagous larvae feed on the olive floral buds and flowers and can be the most accessible prey [47]) in the two years of our study (data under evaluation). However, the ant species highlighted in olive orchards as potential predators of olive pests can have a counter-productive effect on natural enemies [36,37] or boost honeydew producers [48].…”

“…Most of the works cited about ants in olive crops in Andalucía (Spain) [29,[34][35][36][37][38]46] have been carried out mainly in the provinces of Jaen, Granada, and Córdoba, in areas with characteristics different from where this work has been conducted, and other works were carried out in the north of Portugal [30,31,41], which is also very different. The relative importance of the species found in our work, although conducted only in two groves and for one year (2022), gives the picture of some differences in the ant assemblage depending on the area of survey, even in an aprioristically homogeneous area as the south of Spain could be considered.…”

Current Status of the Main Olive Pests: Useful Integrated Pest Management Strategies and Genetic Tools

“…Ants also have beneficial effects in biological control because they consume large numbers of pest insects [105]. For instance, Tapinoma complex, one of the most abundant groups in the olive agroecosystem, is a strong candidate for olive moth control in Spanish olive groves [106]. Indeed, although IPM is certainly important to maintain ant communities and promote their roles as pest control agents, the Tapinoma species seems to be little affected by the landscape heterogeneity [91].…”