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Diversity and abundance of arthropod by-catch in semiochemical-baited traps targeting apple clearwing moth (Lepidoptera: Sesiidae) in organic and conventional apple orchards in British Columbia, Canada

Published online by Cambridge University Press:  11 August 2014

V. Marius Aurelian
Affiliation:
Department of Biological Sciences, University of Alberta, CW 405 Biological Sciences Building, Edmonton, Alberta, Canada T6G 2E9
Maya L. Evenden
Affiliation:
Department of Biological Sciences, University of Alberta, CW 405 Biological Sciences Building, Edmonton, Alberta, Canada T6G 2E9
Gary J.R. Judd*
Affiliation:
Pacific Agri-Food Research Centre, Agriculture and Agri-Food Canada, Box 5000, 4200 Highway 97, Summerland, British Columbia, Canada V0H 1Z0
*
1Corresponding author (e-mail: Gary.Judd@agr.gc.ca).

Abstract

Apple clearwing moth (ACM), Synanthedon myopaeformis (Borkhausen) (Lepidoptera: Sesiidae), is an invasive species and destructive pest of commercial apple trees in British Columbia (BC), Canada. Mass trapping with Concord grape juice and sex pheromone is being developed as an organic pest management tactic. We quantified the diversity and abundance of arthropod by-catch in these traps during the 2009 flight (13 June–31 July) of ACM. Paired traps were deployed in organic and conventionally managed apple orchards planted using different tree densities representing the extremes of the current BC apple industry. Using seasonal by-catch and community-level statistical analyses we determined that family communities of arthropods caught in juice-baited and pheromone-baited traps differed significantly. Yellow juice-baited traps caught a greater variety of arthropod families in greater abundance than pheromone-baited yellow Unitraps®. We show that for each trap type, family communities caught in organic versus conventional orchards were significantly different. Organic orchard management affected abundance of some beneficial taxa, but the sign of the difference depended on the taxon examined (e.g., ladybeetles increased versus lacewings declined). Tree density had no effect on by-catch. Managing ACM by mass trapping may be detrimental to ecosystem services because many nontarget beneficial species are caught. A balanced risk-to-benefit approach should be taken before this technology is widely implemented against ACM.

Type
Insect Management
Copyright
© Her Majesty the Queen in Right of Canada 2014, as represented by the Minister of Agriculture and Agri-Food 

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Footnotes

Subject editor: Staffan Lindgren

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