Contrary to native predators, which have co-evolved with their prey, alien predators often benefit from native prey naïveté. Vespa velutina, a honeybee predator originating from Eastern China, was introduced into France just before 2004. The present study, based on video recordings of two beehives at an early stage of the invasion process, intends to analyse the alien hornet hunting behaviour on the native prey, Apis mellifera, and to understand the interaction between the activity of the predator and the prey during the day and the season. Chasing hornets spent most of their time hovering facing the hive, to catch flying honeybees returning to the hive. The predation pressure increased during the season confirming previous study based on predator trapping. The number of honeybee captures showed a maximum peak for an intermediate number of V. velutina, unrelated to honeybee activity, suggesting the occurrence of competition between hornets. The number of honeybees caught increased during midday hours while the number of hornets did not vary, suggesting an increase in their efficacy. These results suggest that the impact of V. velutina on honeybees is limited by its own biology and behaviour and did not match the pattern of activity of its prey. Also, it could have been advantageous during the invasion, limiting resource depletion and thus favouring colonisation. This lack of synchronization may also be beneficial for honeybee colonies by giving them an opportunity to increase their activity when the hornets are less effective.

Correlated random walks are the dominant conceptual framework for modelling and interpreting organism movement patterns. Recent years have witnessed a stream of high profile publications reporting that many organisms perform Lévy walks; movement patterns that seemingly stand apart from the correlated random walk paradigm because they are discrete and scale-free rather than continuous and scale-finite. Our new study of the movement patterns of Tenebrio molitor beetles in unchanging, featureless arenas provides the first empirical support for a remarkable and deep theoretical synthesis that unites correlated random walks and Lévy walks. It demonstrates that the two models are complementary rather than competing descriptions of movement pattern data and shows that correlated random walks are a part of the Lévy walk family. It follows from this that vast numbers of Lévy walkers could be hiding in plain sight.T urchin 1 argued that correlated random walks are the most influential and practicable approach to describing animal movement patterns. In these models, an individual's trajectory through space is typically regarded as being made up of a sequence of distinct, independent, randomly oriented 'steps'. It has long been recognized that the transformation of an animal's continuous movement path into a broken line is necessarily arbitrary and that probability distributions of steps lengths and turning angles are model artifacts 1 . Nonetheless, for most researchers this shortcoming is not important on a practical level (smoothing out the simulation data will not really change anything) and that the 'problem' can be fixed using 'continuous-time' correlated random walk models in which velocities evolve as a Markovian process [2][3][4] . This position changed somewhat when it was realized that, as a result of auto-correlation of velocities, continuous-time correlated random walk models produce Lévy walk movement patterns 5 ; an increasingly popular but controversial model of animal movement patterns [6][7][8] . Lévy walks comprise clusters of short step lengths with longer movements between them. This pattern is repeated across all scales with the resultant clusters creating fractal patterns that have no characteristic scale because the root-mean-square step-length is a divergent quantity. The distribution of step lengths has a powerlaw tail, p l (l) , l 2m where 1 , m , 3. Lévy walks are controversial, in part, because many early studies had wrongly ascribed Lévy walks to some species through the use of inappropriate statistical techniques 9,10 . More recently, however, studies have provided compelling evidence that many organisms (a diverse range of marine predators, honeybees, mussels, Escherichia coli, T-cells) display movement patterns that can be approximated by Lévy walks, with m < 2, and these have been attributed to the execution of an innate, advantageous searching strategy [11][12][13][14][15][16][17][18] . Continuous-time correlated random walks do, however, present different Lévy walks characteristics. First...