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Successful biological control of winter moth, Operophtera brumata, in the northeastern United States

Cite this dataset

Broadley, Hannah; Elkinton, Joseph; Boettner, George (2020). Successful biological control of winter moth, Operophtera brumata, in the northeastern United States [Dataset]. Dryad.


Winter moth, Operophtera brumata, native to Europe, invaded the northeastern United States in the late 1990s, where it caused widespread defoliation of forests and shade trees ranging from 2,266 to 36,360 ha per year between 2003 and 2015 in Massachusetts. In 2005, we initiated a biological control effort based on the specialist tachinid parasitoid Cyzenis albicans, which had previously been introduced along with the generalist ichneumonid parasitoid Agrypon flaveolatum to control winter moth in Nova Scotia in the 1950s and British Columbia in the 1970s. Due to concerns of possible non-target impacts by A. flaveolatum, we focused entirely on the specialist C. albicans. Each year for 14 years, we collected several thousand individuals of C. albicans from British Columbia and released them across widely-spaced sites in the northeastern United States. As of 2020, we had established C. albicans at 41 of 44 sites from coastal Maine to southeastern Connecticut. By 2016 winter moth densities (pupae/m2) had declined from 100-500 pupae/m2 to 0-10 pupae/m2 at six widely spaced release sites and was coincident with the onset of 10-40% parasitism. At one site in Wellesley, Massachusetts, this decline occurred in 2012 and winter moth densities have remained low for seven subsequent years. Defoliation in Massachusetts has been reduced to undetectable levels since 2016. DNA sequencing of the barcoding region of the mitochondrial gene CO1 confirmed that all C. albicans reared from winter moth matched the C. albicans collected from Vancouver Island and were distinct from parasitic flies (presumably a native species) reared from a native congener of winter moth, Bruce spanworm (O. bruceata). Successful establishment of C. albicans on winter moth represents a rare, if not the only, example of the biological control of a major forest defoliator that attacks a wide range of tree species anywhere in the world by the establishment of a single specialist natural enemy.


See the methods section of the corresponding manuscript. 

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U.S. Forest Service, Award: USDA-FS 13-CA-11420004-236

Animal and Plant Health Inspection Service, Award: AP17PPQS&T00C068