LE3 .A278 2019

2019

Hillier, Kirk
Sweeney, Jon

Acadia University

Master of Science

Masters

Biology

Biology

The invasive beech leaf mining weevil, Orchestes fagi L. (Coleoptera: Curculionidae), is a common pest of beech trees in Europe that has recently established in Nova Scotia, Canada. Adults overwinter and emerge in early spring to feed on and lay eggs in beech leaves. Developing larvae mine beech leaves and cause significant defoliation when populations are high. Successive years of heavy defoliation by the weevil is killing native American beech trees (Fagus grandifolia) in Nova Scotia and the weevil is spreading rapidly. Our main objective was to develop survey tools to monitor the weevil’s spread and detect new infestations as early as possible. By using bioassays and field trapping experiments, we have analyzed the response of O. fagi to auditory, chemical, and visual stimuli to better understand putative attractive cues used by the beetle. Results from field trapping trials in 2017 and 2018 comparing several trap colors, trap types, and the addition of an attractive host volatile suggest that yellow, green, or white sticky prism traps without a host volatile lure are an effective way of detecting O. fagi adults. Additionally, we recorded sounds produced by adult O. fagi under three conditions: male in distress, female in distress, and male in presence of female. Playback of recorded sounds to adult beetles suggest female O. fagi are repelled by sounds produced by distressed males. Taken together, our acoustic results provide a deterrent which could have potential implications in control of this pest, and our trapping experiments suggest an effective means of monitoring the spread of the species in Canada.

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https://scholar.acadiau.ca/islandora/object/theses:3209