Tracking large bees in open landscapes with active radio tags-Advantages and challenges using stationary receivers.

Recent technological advancements have allowed ecologists to study the movement of smaller animals, including insects, using remote tracking methods, such as very-high-frequency (VHF) technology. VHF tracking technology enables us to study migration patterns, spatial behaviour and distribution in ecologically relevant species, thereby supporting the development of effective conservation strategies. We applied VHF transmitters on two European carpenter bee species, Xylocopa valga and Xylocopa violacea, and established a remote tracking approach for insects <1 g. We studied the effect of the tags on the species' flight behaviour and their movement patterns within an open grassland landscape in Central Europe. We provided a detailed description of the application of miniaturised transmitters on the dorsal body of the bees and a step-by-step guide from purchasing the material to constructing stationary receivers. We discussed potential pitfalls of the applied technologies and how to overcome them in the field. Further, we provided a dataset and script to process the information collected by the receivers with open-source software. Our study shows that miniaturised VHF transmitters, in combination with stationary receivers, are a powerful tool for insect movement research. However, ecologists must take great care in selecting the study area and target animals and in analysing the data.