Non-consumptive effects (NCEs) of predators are part of the complex interactions among insect natural enemies and prey. NCEs have been shown to significantly affect prey foraging and feeding. Leafhopper's (Auchenorrhyncha) lengthy phloem feeding bouts may play a role in pathogen transmission in vector species and also exposes them to predation risk. However, NCEs on leafhoppers have been scarcely studied, and we lack basic information about how anti-predator behaviour influences foraging and feeding in these species. Here we report a study on non-consumptive and consumptive predator-prey interactions in a naturally co-occurring spider–leafhopper system. In mesocosm arenas we studied movement patterns during foraging and feeding of the leafhopper Psammotettix alienus in the presence of the spider predator Tibellus oblongus. Leafhoppers delayed feeding and fed much less often when the spider was present. Foraging movement pattern changed under predation risk: movements became more frequent and brief. There was considerable individual variation in foraging movement activity. Those individuals that increased movement activity in the presence of predators exposed themselves to higher predation risk. However, surviving individuals exhibited a ‘cool headed’ reaction to spider presence by moving less than leafhoppers in control trials. No leafhoppers were preyed upon while feeding. We consider delayed feeding as a “paradoxical” antipredator tactic, since it is not necessarily an optimal strategy against a sit-and-wait generalist predator.

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Pollen beetles (Coleoptera: Nitidulidae) are major pests of oilseed rape and other crucifers. Efficient and timely management of these pests can greatly be improved by effective monitoring of their spatial and temporal distribution. In field trials in Hungary, we have discovered striking differences in colour responsiveness among pollen beetle species: Brassicogethes aeneus F. 1775 (earlier Meligethes aeneus) and B. viridescens F. 1775 responded most strongly to fluorescent yellow traps, whereas B. coracinus Sturm 1845, Fabogethes nigrescens Sturm 1845 and Meligethes atratus Olivier 1790 were most attracted to blue or white traps. Differences in the spring flight period were also recorded, with B. aeneus and B. viridescens flying ca. 1 month earlier than the other three species. Further tests established that funnel traps having both fluorescent yellow and blue colour cues are the most efficient in attracting a wide range of pollen beetle species. On the other hand, fluorescent yellow traps can be used to detect and monitor B. aeneus specifically.