New Invasive Fruit Fly Pest

Last Update Posted: 8/17/2012. The first Spotted-wing Drosophila of the 2012 season for Maine was found in a trap in Limington (York County) on Friday, July 13th.  Since that time, it has been found in traps at locations in Buxton, Springvale, Bowdoinham, Dresden, New Gloucester, Poland Spring, Mechanic Falls, Turner, Farmington, Wales, Litchfield, Fayette, Thorndike and Warren. During the final week of July, additional captures occurred in Buxton, Bucksport and Franklin, in addition to more captures at the earlier locations. In addition, traps in wild blueberry fields in Hancock and Washington counties have caught flies during the past week. At this point we expect that the fly is fairly widespread and active through most, if not all, of the southern, mid-state and coastal regions of the state. 

For the most recent update posted by Highmoor Farm for Maine fruit growers, visit their latest blog posting.

It is important to understand that the traps are unlikely to provide early warning, i.e. when we find them in a trap they are probably already established in that area and in that particular soft-skinned fruit crop.

Trapping / monitoring efforts for this fly are ongoing.

Report first posted December 8th, 2011
A new, invasive fruit fly pest, Drosophila suzukii, has spread into Maine.  It’s called the Spotted-wing Drosophila, or SWD for short.  It is an invasive insect from China & Japan, and was confirmed in Litchfield, New Hampshire on September 6th, 2011.  Throughout the months of September and October, it was confirmed at several locations in Maine (mostly southern Maine thus far) where traps were set out.  Confirmations were made in one town in Lincoln County, one town in Kennebec County, another town in Franklin County, and two towns in York County.   The SWD flies turned up fairly heavily in fall raspberries in three of those locations, strawberries in another location, and at a greenhouse tomato operation at a fifth location.  This fruit fly, in addition to the spots found on the wings of the males, is distinctive in that the females are armed with a serrated (saw-like) ovipositor for depositing their eggs, which means that ‘healthy’ fruit with an intact, unbroken skin, may not be immune from attack and even fruits with relatively hard skins have cause to be concerned, which is why plans are well underway to conduct extensive trapping throughout 2012 to try to get a clearer handle on what dangers Maine fruit growers might be facing from this new pest.

For more information:

• MPBN Radio Story with UMaine Extension Pest Management Specialist, Jim Dill
• [1/9/2012] Researchers Discover Destructive Fruit Fly Now in Maine
• Instructions (Maine) for Traps for SWD
• SWD Alert authored by entomologist, Alan Eaton, at the University of New Hampshire Cooperative Extension.
• Michigan’s SWD Site (Michigan State University)
• SWD Management (Penn State)
• USDA & North Central IPM Regional Pest Alert

Tags: Drosophila suzukii, fall raspberries, fruit flies, fruit fly pest, invasive fruit fly, Maine fruit growers, raspberries, spotted-wing drosophila, strawberries