Title: Long-term monitoring of the introduced emerald ash borer (Coleoptera: Buprestidae) egg parasitoid, Oobius agrili (Hymenoptera: Encyrtidae), in Michigan, USA and evaluation of a newly developed monitoring technique
Author: Abell, Kristopher J.; Bauer, Leah S.; Duan, Jian J.; Van Driesche, Roy.;
Source: Biological Control. 79: 36-42.
Publication Series: Scientific Journal (JRNL)
Description: Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a serious invasive pest of ash trees (Fraxinus spp.) in North America from China. The egg parasitoid Oobius agrili Zhang and Huang (Hymenoptera: Encyrtidae) was introduced from China as a biological control agent for this pest in Michigan and throughout the infested area of the United States. A critical component of any biological control program is post-release monitoring and evaluation; however, because of the small size and cryptic nature of O. agrili, evaluation of its impact is difficult. We compared two methods for measuring parasitism of emerald ash borer eggs: (1) timed visual searches of bark on standing ash trees and (2) bark collection, sifting, and sorting. Both methods were carried out in paired parasitoid-release and control plots, the visual search method over a six-year period (2008-2013) and the more recently developed bark-collection and sifting method for 2 years (2012-2013). The visual search method found parasitism in release plots remained low (0.7-4.2%) in samples taken from 2008 to 2012 and reached 10.6% in 2013. In comparison, the bark-sifting method found that rates of egg parasitism were considerably higher in release plots, 21.8% and 18.9% for samples taken in 2012 and 2013, respectively. These findings indicate that the population-level impact of O. agrili is increasing and may be an important source of mortality for EAB populations. We recommend the bark-collection and sifting method as the more effective method to recover parasitoids and estimate parasitism rates of O. agrili.
Keywords: Invasive species, Parasitoid release and recovery, Natural enemy introduction, Parasitoid recovery methods
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
XML: View XML
Abell, Kristopher J.; Bauer, Leah S.; Duan, Jian J.; Van Driesche, Roy. 2014. Long-term monitoring of the introduced emerald ash borer (Coleoptera: Buprestidae) egg parasitoid, Oobius agrili (Hymenoptera: Encyrtidae), in Michigan, USA and evaluation of a newly developed monitoring technique. Biological Control. 79: 36-42.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility