Evaluation of asian hornet (Vespa velutina) trappability in Alto-Minho, Portugal: commercial vs. artisanal equipment, human factors, geography, climatology, and vegetation

Abstract

Trapping the Asian hornet remains a viable alternative to monitor its presence, dispersion, and ecological niche. With the objective of evaluating the effectiveness of baits and traps, an Asian hornet (Vespa velutina) capture trial was conducted using combinations of artisanal and commercial baits and traps. The second objective was to explore the relationship between the species’ dispersal patterns and the influence of human, geography, climate, and vegetation factors, to identify the preferred conditions for its colonization. We identified beekeepers in the Alto Minho region of Northern Portugal, where the different combinations of baits and traps were placed. The traps were monitored from February to September 2023, and the captures were counted. The temporal variation of the captures showed a first peak at the beginning of April, corresponding to primary workers. In September, when the trial was halted, the second peak, corresponding to secondary workers, had not yet been reached. The peaks of captures were used to fit models to allow the characterisation of their ecological niche. Statistical analysis of the captures revealed no significant differences. It was concluded that there is no advantage in using the commercial devices and baits tested. The ecological niche where the higher number of captures is observed is characterised by an abundance of vegetation, humidity, and higher temperatures. Elevation and slope also favour the presence of the Asian hornet.