Asian Lady Beetles in Delaware: How to Spot Them and Keep Them Out

What they look likeSignsAre they dangerous?How we treat themPreventionFAQ

What do they look like?

Multicolored Asian lady beetles are about 1/4 inch long and pale yellowish-brown to bright orange-red. Most have 19 spots, though some are faint or missing. The best ID mark is behind the head, where white markings form the shape of an M. The larvae are black and shaped like little alligators, with orange stripes on the sides.

Signs you have them

• Large groups of beetles in the attic, basement, or living areas in fall
• Beetles on windows on warm winter days
• Yellow-orange stains where beetles were crushed

Are they dangerous?

These beetles are a nuisance pest. When crushed, they release a yellow-orange liquid that can stain fabric and walls. The bigger hassle is numbers. In fall the adults appear to give off a chemical signal that draws large groups to the same building, so they can fill attics, basements, and living areas.

When are they active?

In fall, adults look for indoor spots to spend the winter. They often show up on windows on warm winter days.

How Wolfe treats them

With lady beetles, keeping them out is the job. UMD Extension recommends sealing in late summer and early fall, before they move in. We help you find the gaps around windows, vents, and siding as part of our fall invader service. For beetles already inside, vacuum them up instead of crushing them. Call us at (302) 697-8969 to get on the schedule.

How to keep them out

• Caulk cracks and seal gaps around windows in late summer and early fall.
• Put screening over vents.
• Vacuum beetles that get inside and release them outdoors.
• Don't swat or crush them, since they stain.

Common questions

Sources: University of Maryland Extension: Multicolored Asian Lady Beetle

Last reviewed October 2026 by Wolfe Pest Control.