Iberian oak savannahs are traditional silvopastoral systems in which acorns constitute a key food source for livestock. Acorn feeding insects provoke significant economic losses; however, the high natural value of Iberian oak savannahs precludes any chemical treatment. This paper shows a novel way of biological pest control based on promoting livestock predation on these insects. Female Curculio elephas (Coleoptera: Curculionidae) oviposit into developing acorns, which are prematurely abscised before reaching their potential size. Larvae still spend 20 days feeding on the cotyledons after acorn drop, being during this period very vulnerable to predation by livestock. We experimentally assessed that cows, pigs and sheep ate sound and infested acorns in the same proportion, so that infestation rates were lower in those Iberian oak savannahs in which livestock density was higher. An effective biological control of Curculio elephas weevils should involve an early predation of infested acorns by livestock, preferentially within 10 days after falling. Doing this, most larvae will be predated before completing their development and, in addition, the nutritional value of infested acorns will still be high (cotyledons not yet depleted by weevils). We encourage landowners to increase livestock densities during September–October, when the infested acorn dropping peaks. These increased densities should rotate over the farm and be maintained at the same plot for a maximum of 3 years in a row. Otherwise, a prolonged and concentrated livestock predation on sound acorns and seedlings would hamper long-term oak regeneration.

伊比利亚橡树大草原是传统的牧林系统，橡子是牲畜的重要食物来源。橡子喂食的昆虫引起了巨大的经济损失。但是，伊比利亚橡树大草原具有很高的自然价值，因此无法进行任何化学处理。本文展示了一种基于促进这些昆虫的家畜捕食的新型生物害虫防治方法。雌性Curculio elephas（鞘翅目：Curculionidae）排卵成发育中的橡子，在达到其潜在大小之前过早脱落。幼虫掉落橡子后，仍需花费20天的时间来喂养子叶，在此期间，它们非常容易被牲畜捕食。我们通过实验评估了母牛，猪和绵羊吃的声音和受害橡子的比例相同，因此那些牲畜密度较高的伊比利亚橡树大草原的侵扰率较低。有效的电蚊的生物控制。象鼻虫应提早被牲畜侵害橡子，最好是跌倒后10天内。这样做，大多数幼虫会在其发育完成之前就被捕食，此外，被侵害的橡子的营养价值仍然很高（尚未被象鼻虫耗尽的子叶）。我们鼓励土地所有者在9月至10月，即出没的橡子下降高峰时提高牲畜密度。这些增加的密度应在整个农场中轮换，并在同一块土地上连续最多保持3年。否则，长时间，集中地捕食合理的橡子和幼苗的牲畜将阻碍橡木的长期再生。