Different responses of Monochamus galloprovincialis and three non-target species to trap type, colour, and lubricant treatment

Abstract

With the increasing threat to forests in Europe from the invasive pine wood nematode (PWN) Bursaphelenchus xylophilus, effective methods are needed to monitor and reduce populations of its insect vector, the pine sawyer beetle Monochamus galloprovincialis. In the present study, we tested the effectiveness of different trap types (multiple-funnel, cross-vane, and triangular), colours (black, white and clear), and lubricant (polytetrafluoroethylene, PTFE) treatments (different PTFE formulations and timing of trap treatment) on the catches of M. galloprovincialis and three most commonly captured non-target beetle species (the xylophagous Spondylis buprestoides and two predators, Thanasimus formicarius and T. femoralis) in Poland. Of the traps not treated with PTFE, the white and black 6-funnel traps were most effective in trapping M. galloprovincialis beetles, while the catches in the cross-vane traps (both white and clear) were low. Trap treatment with PTFE significantly increased trap effectiveness, regardless of PTFE type and time of application. The catches of S. buprestoides were affected by trap type, while those of T. formicarius depended on trap colour and size. Both species seem to respond positively to ethanol and/or α-pinene in the lure composition. PTFE treatment had a significant effect on the catches of T. femoralis. In conclusion, for the monitoring of M. galloprovincialis, we recommend the white cross-vane traps treated with dry PTFE. They are less but still effective in catching the target species, while their use, together with lures containing no ethanol and α-pinene, greatly reduces the catches of non-target insects S. buprestoides and T. formicarius.