Behaviour of male European corn borer, Ostrinia nubilalis Hubner (Lep.: Crambidae) towards pheromone-baited delta traps, bucket traps and wire mesh cone traps

Pheromone-baited traps are used to monitor the flight of European corn borer (ECB; Ostrinia nubilalis). Traps of various designs are available: bucket traps, delta sticky traps and wire mesh cone traps. However, these traps are not all equally efficient and little is known about the reasons for this difference in efficiency. We investigated the behaviour of ECB males towards bucket traps and delta traps by means of observation in a wind tunnel. We also carried out observations and capture trials with delta traps and wire mesh cone traps in field conditions. Our laboratory studies showed that ECB males were not optimally attracted and were poorly captured by a pheromone baited bucket trap. Furthermore, they were shown to readily enter delta traps in the wind tunnel but were caught after more than three passages through this trap. Field studies showed that wire mesh cone traps captured approximately six times more ECB males than delta traps. Observation of the behaviour of ECB males showed that this difference was due to more efficient moth capture rather than greater attraction of the moth. In total, 31.5% of the 219 males observed close to wire mesh cone traps were caught, vs. 2.5% of the 520 males observed close to delta traps. This greater efficiency is due to a better capture rate of the attracted males by wire mesh cone traps than by delta traps.