In the last decades, biological invasions have increased worldwide and alien species are often considered one of the major threats to biodiversity. Social hymenopterans are prone to be successful at colonization because sociality promotes flexibility. Several Vespidae are invasive throughout the world and impact local ecology, economy, and human health. The Yellow-legged hornet (Vespa velutina) was introduced into southwestern France before 2004. Since its accidental introduction, its population has expanded through the French territory but also to Spain, Portugal, Italy, Germany, and more recently the UK. This social Hymenoptera is a predator of honeybees. However, contrary to their Asian counterpart (Apis cerana), European honeybee (A. mellifera) does not display efficient anti-predator behaviour. Hornet workers prey intensively on honeybees to feed their larvae. For several years, beekeepers face heavy losses in their livestock due to different factors (pesticides, Varroa, habitat fragmentation, and losses) and V. velutina is thus an additional source of stress for honeybees, potentially contributing to their decline in Europe. Little is known about V. velutina (except its hunting activity on honeybees). The knowledge of the ecology and behaviour of this invasive pest is thus of major interest to provide an efficient management program (see our recent review [PDF]).