However, when they were outside the mean hovering distance (Cdxz = 5 in Fig. 6), they came significantly nearer to the nest as soon shimmering had started.
Third, when the hornets were closer than the mean hovering distance, they withdrew from the nest in the course of shimmering.
Second, at the mean hovering distance, hornets were not affected by shimmering; they stayed neutral with regard to approaching or leaving the nest site.
Thus, the capacity of shimmering to repel wasps is limited to a distance of around half a meter from the nest, which equals the mean hovering distance.
Summarizing, the authors conclude that at distances greater than the mean hovering distance, hornets tended to approach the nest under the influence of shimmering.
For that, two groups were distinguished regarding their distance to the nest, that is, when they were (a) nearer than the hovering distance (dxz<45 cm) or (b) when they were outside the mean hovering distance (dxz>45 cm).
This is expressed by the negative vdxz and θxz values in Fig. 7B,C (yellow symbols), which coincide with the values of the wasp outside the mean hovering distance (Cdxz = 5) in Fig. 6.
Furthermore, most of the hornets flew within the mean hovering distance of dxz = 52 cm (dashed line in Fig. 5A,C) and slower than 50 cm s−1 (Fig. 5B) when they provoked shimmering.
Second, when the hornets were close to the nest, in particular inside the mean hovering distance, the hornets turned off from the honeybee nest as soon as the shimmering wave became sturdy (scenario B).
It is known that Apis dorsata colonies, which had mobilized their guards for a potential counter attack, recognize predatory birds at much greater distances from the nest than the mean hovering distance of wasps.
