Mayflies (shadflies and lake flies) are aquatic insects that have two pair of wings, they are not related to house flies or other true flies. They are attracted to light and become a pain when they collect at night near doorways in large numbers. Make the house less attractive to mayflies by changing from white bulbs to yellow l.e.d. bulbs or moving the light away from entrance. Also. consider reducing the light that shines from windows to avoid attracting mayflies to them at night. Insect light traps that use UV light with sticky pads is useful in attracting mayflies away from the building.
https://gogreenpestcontrol.ca/mayflies/
gogreenpestcontrol.ca insectandrodentexterminators.com Delta Ladner Tsawwassen B.C., Randy Bilesky BsF CPA RPF
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