RT Journal Article T1 Livestock as a biological pest control: Experimental validation for oak savannas A1 Canelo, Tara A1 Bogdziewicz, Michal A1 Pérez Izquierdo, Carlos A1 Gaytán, Álvaro A1 Bonal Andrés, Raúl AB Ungulates consume plants and seeds together with the insects that feed on them, which have consequences at the ecosystem level. We carried out an experiment to assess the effects of intraguild predation by livestock on the main acorn pest (Curculio spp. weevils) in Iberian oak Quercus spp. dehesas, a widespread traditional agroecosystem. Acorns are a key food source for free-range livestock (especially pigs), but, if properly managed, livestock could become a pest control agent.In three dehesa farms, we replicated eight experimental trios, each including one tree from which livestock was excluded, another from which all dropped acorns were removed manually (simulating intensified predation by livestock), and a control one in which livestock was allowed at standard densities. Removal of marked infested acorns by livestock, adult and larval weevil numbers, and acorn production/infestation rates were recorded at all trees.Livestock predated most weevil larvae within the prematurely dropped infested acorns before larvae had time to finish development. Hence, in those trees subjected to intensified predation, the local number of larvae decreased. Consequently, adult weevil abundance in the following year was lower than in trees within the exclosures of livestock.The consequence of the decrease in the number of adults was a reduction in the rates of acorn infestation in control oaks and intensified predation compared to those excluded from livestock (8% and 20%, respectively). C. elephas mobility is low, especially when trees are isolated, and acorn infestation is greatly dependent on the number of weevils emerging beneath the canopy of each oak. Therefore, a locally focused elimination of infested acorns may succeed in reducing the negative impacts of the pest.Synthesis and applications: We suggest intensifying livestock predation on prematurely dropped-infested acorns by allowing livestock foraging from October 1st onward. Pigs are usually released free range in early November, once weevil larvae have completed their development and escaped predation. The proposed management would increase the availability of healthy acorns, thus increasing the farm capacity and the economic profit by up to 20%, tens of millions of euros of additional profits when translated into the prices of the Iberian pork market. PB Wiley SN 0021-8901 YR 2025 FD 2025 LK https://hdl.handle.net/20.500.14352/120951 UL https://hdl.handle.net/20.500.14352/120951 LA eng NO Canelo, T., Bogdziewicz, M., Pérez-Izquierdo, C., Gaytán, Á., & Bonal, R. (2025). Livestock as a biological pest control: Experimental validation for oak savannas. Journal of Applied Ecology, 62, 824–833. https://doi.org/10.1111/1365-2664.70012 NO This work was supported by the Spanish Ministry of Economy and Competitiveness (AGL2014-54739-R) and the European Regional Development Fund (FEDER, European Union). Raúl Bonal was funded by the Atracción de Talento Investigador Programme (Gobierno de Extremadura) (TA13032). Tara Canelo benefited from a Ayuda del Programa de Recualificación del Sistema Universitario Español - Margarita Salas (NextGeneration EU), Ministerio de Universidades (MS-20). Michal Bogdziewicz was supported by the Polish National Science Centre grant 2019/35/D/NZ8/00050. NO Ministerio de Economía y Competitividad (España) NO Ministerio de Universidades (España) NO European Commission NO Gobierno de Extremadura NO Polish National Science Centre DS Docta Complutense RD 21 dic 2025