There are relatively few studies that have evaluated how ULV sprays affect non-target insects like bees and other insects. Current studies show mixed results, where some find a negative impact (2012 paper) and others do not (2018 paper).
However, other studies have found synthetic pesticides harmful to pollinator physiology, behavior, and foraging methods (2021 paper).
It is also unclear how the pyrethroids that commercial companies apply to the barriers/edges of properties affect beneficial insects. So far, only two studies have evaluated this, and they have found that these sprays negatively impact monarchs (2006 paper) and honey bees (2022 paper).
Overall, this is an area that needs more research. The chemical, timing of spray application, spray droplet size, and more have influence on the effectiveness against mosquitoes as well as their effects on beneficial insects.
Furthermore, studies that examine effects of mosquito-sprays have primarily evaluated how these impact honey bees. While honey bees are important pollinators, little research has looked at the effects on native bee populations.
Our study will fill some of these research gaps. Specifically, we will examine the impacts of pyrethroids used by health departments and commercial companies on native bee species in Ohio. We will also evaluate how effective these sprays are in reducing mosquito populations.