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The 2015 trapping season is underway and first detection of SWD has occurred in Ontario, Canada and New York State. This is certainly earlier than in 2014! It is also the earliest trap catch reported for New York since this invasive arrived here in 2012. Typically, a single trap (out of four) is catching a single female, indicating counts are low. Eggs laid by those females will become adults in about a week's time.

Low trap catch counts are a good alert for you to get ready to protect your crops. We have updated the quick reference tables for insecticides for berries, tree fruit and grapes. Step up fruit monitoring in your June strawberry fields. Be vigilant of your summer raspberry plantings and know when ripe fruit are developing. Consider protecting sweet cherry and tart cherry with an insecticide targeted at SWD in your treatment program. Keep tabs on reports from your county from our monitoring network via the SWD blog.

In NY, first catch was reported from one research site in the Finger Lakes—a single female SWD in a trap on the edge of a summer raspberry planting in Schuyler County, NY—using a commercially available Sentry lure with unscented soapy water as the drowning solution. New this season, I'll be reporting research findings comparing different lures for trapping SWD from Long Island, the Hudson Valley, and the Finger Lakes regions of NY. These reports aren't included on the NY distribution map.

In Ontario, Canada they have found low numbers of flies at sites in Essex, Norfolk, Oxford, and Halton counties and the Niagara and Durham region; three of the sites were in blueberry plantings. This is about three weeks earlier than normal for Ontario Province. On their ONfruit blog is an excellent photograph of what an infested strawberry will look like—note the sunken spot on the fruit surface.

Male SWD on blackberry in August.
Male SWD on blackberry in August.

Sixteen cooperators with Cornell Cooperative Extension and the College of Agriculture and Life Sciences will be monitoring approximately 134 traps at 50 locations in 29 Counties in NY (Albany, Cayuga, Chemung, Clinton, Columbia, Dutchess, Erie, Essex, Genesee, Herkimer, Livingston, Monroe, Niagara, Onondaga, Ontario, Orange, Orleans, Rensselaer, Saratoga, Schuyler, Seneca, Steuben, Suffolk, Tioga, Ulster, Washington, Wayne, Wyoming, and Yates). No first catch reports have come in from these sites as of this writing. Our goal is to monitor SWD until first catch and report this on the blog and on the NY SWD distribution map so growers can protect their crops.

Historic look at first catch reports in NY
In 2012, first report by rearing (two week lag time) was on June 27, in June strawberry, Monroe County.
In 2012, first catch was on July 6, in sweet cherry, Yates County.
In 2013, first catch was on June 11 in woods, Ontario County.
In 2014, first catch was on July 9 in raspberry, Suffolk County.
In 2015, first catch was on June 18, in raspberry, Schuyler County.

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Reports have come in from Southwest Michigan by Rufus Isaacs, Michigan State University, and Middlesex County in Connecticut by Rich Cowles, CT Agricultural Experiment Station of first catch of SWD. As of today, no one in the NY monitoring network has reported trap catch of SWD. Although the catch in Michigan was of several adults, the report from CT was of a single male.

Because this finding in central CT is of a single adult, don't interpret this as meaning that ripe fruit is immediately at risk.  What we have observed in the past is that we can capture a lone adult here or there, but it isn't until we get sustained captures in traps set in susceptible fruit plantings that growers are at risk of infestation.

On Long Island, fruit samples contained no evidence of infestation this week nor were any SWD caught in traps set there in Suffolk County. No other reports of SWD caught in traps have come in from NY. But do stay tuned. The number of other fruit flies being caught in my traps in Wayne County, Sodus Bay area, jumped significantly this week from around 150 per trap last week to almost 1000 other fruit flies per trap.

Although the heat has been unbearable in places...let's cheer, because SWD adults are intolerant of temperatures much above 90F.

Typically, SWD trap catch continues to increase - hundreds/week - peaking in late fall. In Oregon and Washington, SWD counts in traps have about doubled each week over the last four weeks; the pressure is the highest experienced since SWD's introduction to that region in 2009. In North Carolina, where SWD arrived in 2010, high numbers are being caught in traps with fruit infestation nearing 100%. In Rhode Island, where SWD arrived in 2011, late season trap counts in the thousands are derived from an aliquot taken of the total trap contents. First found in 2012 in Colorado, this year it's across the state in very damaging numbers. Is this because as fruit quality declines traps become more attractive to SWD? Is it because adult SWD can live for 20-30 days and during that time can lay >350 eggs so that, by end of summer and into fall, there has been an exponential explosion in population numbers? Answers to these questions and more will be discussed in November by entomologists at a National SWD meeting of the The USDA Multistate Project: SWD Biology, Ecology, and Management, covering these four focus areas:

  1. Biology and ecology of SWD and how it may vary by location, plant host, and season.
  2. Reliable, easy-to-use traps, lures, and methods for monitoring SWD adults and larvae.
  3. Laboratory and field research on developmental parameters and temperature tolerance limits to develop and validate a degree-day model.
  4. Effective cultural, biological, and chemical control tactics for sustainable IPM plans for at-risk crops in the US.

As of July 15, spotted wing drosophila females have been found in summer red raspberry plantations in several locations in PA and a few females were found in traps in blueberries in Adams County. Read the SWD Update from Kathleen Demchak, Senior Extension Associate, and David Biddinger, Tree Fruit Research Entomologist, Pennsylvania State University.

The first SWD of the season was confirmed on June 19, 2013 by Heather Faubert, University of Rhode Island. A single male was caught in an apple cider vinegar/yeast insert dual trap set up in a cherry tree in Newport County, Rhode Island. Cherries were collected to check for oviposition. (Accumulated GDD 508, day langth 15:08)

One female spotted wing drosophila (SWD) was caught on June 10, 2013 in Massachusetts, Hampshire County, as reported by Sonia Schloemann, UMass Extension Fruit Specialist, UMass Center for Agriculture. Read more in Massachusetts Berry Notes. A female SWD has the capacity to lay over 350 eggs during her 20- to 30-day life span. The trap was set in the unsprayed edge of a farm with multiple fruit crops, closest to the primocane raspberry field. (Accumulated GDD 515, day length 15:09)

SWD female found in MA June 10, 2013
SWD female found by Sonia Schloemann in Massachusetts; inset shows the characteristic serrated ovipositor.
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