Asian Ladybugs (Harmonia axyridis)

About Asian Ladybugs (Harmonia axyridis)

Activity: Seasonal Invaders in Search of Warmth

Asian ladybugs, also known as multicolored Asian lady beetles, are most active in the fall, when they seek shelter indoors to escape the cold. Unlike native ladybugs, these invaders gather in large numbers, clustering on walls, windows, and inside homes. While harmless outdoors where they control aphid populations, indoors they become a nuisance pest, emitting unpleasant odors and sometimes biting when disturbed.

Diet: What Asian Ladybugs Eat & Why It Matters

Outdoors, Asian ladybugs are beneficial predators, feeding on:

• Aphids, scale insects, mites, and other soft-bodied pests

• They help reduce garden pest populations naturally
  However, when they move indoors for overwintering, their presence serves no beneficial role and can lead to allergic reactions or staining from their defensive secretions.

Size: Small but Noticeable

• Adult Asian ladybugs measure about 6 to 10 mm in length

• They are recognizable by their orange, red, or yellowish coloration with varying black spots

• A distinct "M" or "W" shaped marking is often visible behind their head (on the pronotum)
  Their large swarms and preference for indoor overwintering distinguish them from native ladybugs.

Nesting Habits: Where Asian Ladybugs Live

Asian ladybugs don't build nests indoors but gather in:

• Warm, sunny sides of buildings

• Cracks and crevices around windows, doors, siding, attics, and wall voids

• They can remain dormant through the winter but become active again on warm days, appearing indoors
  In spring, they attempt to exit homes, often reappearing inside as temperatures rise.

Why Professional Treatment Is Crucial

While not structurally damaging, Asian ladybug infestations can:

• Cause staining on walls, curtains, and furniture from their yellowish defensive secretions

• Trigger allergic reactions and respiratory issues in sensitive individuals

• Become overwhelming due to their massive swarming behavior
  DIY methods like vacuuming only offer temporary relief. Professional pest control ensures effective exclusion, treatment, and prevention of future invasions.

Signs of an Asian Ladybug Infestation

Watch for these indicators of infestation:

• Large clusters of ladybugs on exterior walls, especially in fall

• Ladybugs appearing indoors near windows, light fixtures, or ceilings

• Foul odor or yellow stains from defensive secretions

• Activity increases on sunny, warm winter days inside homes

Understanding the Problem: Asian Ladybug Infestations

Asian ladybugs exploit:

• Cracks, vents, poorly sealed windows and doors to access homes

• Without intervention, they can return each fall, using pheromones to attract others
  Surface cleaning won’t address the root cause. Professional exclusion techniques and targeted treatments are necessary for long-term control.

Our Professional Approach to Asian Ladybug Control

 Detailed Inspection

Identifying entry points and areas of congregation.

 Targeted Insecticide Treatments

Applying safe, effective products to infested areas and potential entry points.

 Exclusion & Sealing Services

Sealing cracks, gaps, and other access points to prevent future invasions.

 Preventive Measures

Installing screens, door sweeps, and providing advice for ongoing protection.