The first & sustained trap captures of spotted wing drosophila (SWD) have been reported over the two weeks in many locations throughout NY state. First trap captures were reported in Orleans and Schuyler this week. Numbers remain very low in most places (<5), aside from two locations in Suffolk and one location in Wayne County where populations increased dramatically this week!
A heatwave over the past week across the state has included high temperatures in the upper 90’s (F) in most of the state with heat index values of 100+ degrees (F). It means phenomenally bad conditions to be out working. The good news is that this may also include fruit flies! As Julie reported on the SWD Blog in 2014, lethal temperatures for various drosophila were tested by scientists in 2004 (Kimura 2004). To test SWD’s temperature tolerance, flies were held at constant temperature in dark for a 24-hr period to determine the lethal temperature (LT) at which 25%, 50%, and 75% of the flies died. In this work, SWD died at and above 90 F.
Populations are specific to site, year, and conditions, and populations can increase rapidly. It is critical to monitor at your location to have the best information for deciding management actions.
First captures have been reported this season the following counties:
- Clinton
- Dutchess
- Essex
- Orleans
- Rensselaer
- Schuyler
- Suffolk
- Tioga
- Wayne
Weekly SWD trap captures by location across NY in 2025
Thank you to all of our collaborators for servicing SWD traps across the state!