I saw one earlier this week. Then a few more as of this writing. The Asian lady beetles are making their annual move into protected areas to spend the winter. And your home is a great place for them to go.
Lady beetles are insects that are absolutely beneficial. But they are not invading your home to cause problems, only to stay warm. The lady beetle does not chew or bore holes in walls nor do they eat carpet or any food in the pantry.
Lady beetles have been considered one of our most beloved insects. They are in stories, a good luck charm for some, and I’ve even seen kids dress up as one for Halloween. Most people grew up calling the lady “bugs”.
If you grew up and don’t remember seeing as many, you are absolutely correct. There is a native lady beetle that is harder to locate and a multitude of non-native lady bug insects that are native to Asia but in the past few decades have spread to many areas of the United States.
This beneficial (yet sometimes controversial) Asian relative was released in the United States as early as 1916. More were released in the late 1970’s and again in the early 1980’s. It has taken years for the populations to spread, but now large populations are found in many areas of the south.
The lady beetle is an effective and natural control for harmful plant pests such as aphids, scale, and other soft-bodied arthropods. One adult lady beetle may eat over 5,000 aphids during its lifetime.
Adult lady beetles can have a variety of colors and spots. The larvae are soft-bodied, gray and orange, and covered with rows of black spots.
While they cause no harm, their overwintering habits inside people’s homes causes them to be a nuisance. A few folks ask if they bite. Well, sort of.
Lady beetles have mandibles, a jaw-like part of their mouth that they use to capture and eat their prey. And while they are not out to bite (like a fire-ant) or sting (like a hornet), they can certainly give someone a good pinch on the skin with those mandibles.
The lady beetle also has a defense mechanism. If agitated or disturbed, the beetle’s reaction is to “reflex” bleed in which a yellow fluid with an unpleasant odor is released from the leg joints. This reaction helps prevent predators, such as birds, from eating the lady beetle.
And yes, this fluid can sometimes stain walls and fabrics.
The lady beetle is attracted to lighter colors such as whites, grays, and yellows. They enter homes through cracks and crevices. During warm winter days and early spring, the lady beetle may become more active searching for an exit.
No real control of these beneficial insects is warranted as it is for termites or destructive insects. Homeowners can prevent them from entering the home by caulking exterior cracks and crevices. And the only “control measures” for them would be sweeping and vacuuming them up to release them back outside.
