Yes. In many parts of the United States, invasive Asian lady beetles have become more common than native ladybug species.

 

Understanding Asian Lady Beetles vs Native Ladybugs

 

“Ladybugs” is a common name for small, round beetles in the family Coccinellidae. Native ladybugs (also called ladybird beetles) include species like the seven-spot and the two-spotted ladybug. In contrast, the Asian lady beetle (Harmonia axyridis) was introduced from Asia to control crop pests. Over time, it spread across North America and Europe.

 

Reasons for the Prevalence of Asian Lady Beetles

 

• Broad diet: Asian beetles eat a wide range of pests, so they thrive even when native species struggle.
• Strong survival traits: They tolerate cooler winters and hotter summers better than many native ladybugs.
• Lack of predators: Local birds and insects often avoid them because their body fluids taste unpleasant.
• Aggressive reproduction: One female Asian beetle can lay hundreds of eggs, leading to rapid population growth.

 

Impact on Ecosystem and Homes

 

• Competition: Asian lady beetles outcompete native ladybugs for food and habitat, reducing biodiversity.
• Indoor invasions: In fall, they gather on and inside buildings to overwinter. You may find clusters in attics or wall voids.
• Staining and odors: When disturbed, they release a yellow fluid that can stain walls, fabrics, and emit a strong smell.
• Allergic reactions: Some people develop skin irritation or respiratory issues when in contact with many beetles.

 

Identifying Asian Lady Beetles

 

• Shape and size: About 5–8 mm long, nearly hemispherical.
• Color variations: Orange to red with zero to 22 black spots, often more variable than native species.
• Pronotum mark: A distinctive black “M” or “W” shaped mark on the white area behind the head.

 

Managing and Preventing Infestations

 

• Seal entry points: Caulk and weather-strip around windows, doors, and siding cracks to block beetle access.
• Install screens: Fit fine-mesh screens on vents and chimneys to keep them out.
• Vacuum removal: Use a handheld or shop vacuum with a filter bag to gently remove beetles without crushing them.
• Professional assistance: For large infestations, licensed pest specialists can apply targeted treatments and advise on long-term prevention—residents in Nashua and beyond face this common challenge each autumn.