Ladybugs are often seen as harmless, beneficial insects, symbols of good luck. This perception, however, can be misleading, as some species of these beetles do bite. While most native ladybug species are gentle, certain introduced species can bite humans. This article clarifies which ladybugs are responsible for these bites and the reasons behind their actions.
Identifying the Biting Species
The primary culprit behind ladybug bites is the Asian Lady Beetle, scientifically known as Harmonia axyridis. This species was intentionally introduced to North America and other regions to help control agricultural pests like aphids and scale insects. Unlike many native ladybugs, Asian Lady Beetles tend to aggregate in large numbers and seek shelter indoors during colder months.
Distinguishing the Asian Lady Beetle from native ladybug species is important. While native ladybugs are typically bright red and round, Asian Lady Beetles exhibit a wider range of colors, including orange, yellow, and black. They are often slightly larger and more oval-shaped. A key identifying feature is a distinct black “M” or “W” shaped marking on the white area behind their head, though its prominence and the number of spots can vary.
Why Ladybugs Bite
Asian Lady Beetles bite for several reasons, none involving aggression towards humans. One common circumstance is self-defense; if a beetle feels threatened or is handled roughly, it may bite as a defensive mechanism. They may also bite when seeking moisture or salt, sometimes mistaking human skin as a potential source.
Another reason for bites relates to their overwintering habits. When these beetles aggregate in large numbers inside homes during cooler months, they can become a nuisance. If disturbed indoors, they may bite as an exploratory action or when disoriented. Their mouthparts are typically used for consuming aphids and other small insects.
What to Expect from a Ladybug Bite
A bite from an Asian Lady Beetle is generally described as a mild, fleeting pinch or prick. The sensation is often less painful than a mosquito bite and typically does not break the skin.
Visually, a bite usually results in a small, red mark that may have slight swelling. This mark is often non-itchy and tends to disappear quickly, typically within a few hours to a day. Ladybug bites are generally harmless and do not transmit diseases. While allergic reactions are rare, some individuals may experience more pronounced symptoms like itching, hives, or swelling if they are sensitive to proteins present in the beetle’s body.
Responding to and Avoiding Bites
If a ladybug bite occurs, the first step is to gently wash the affected area with soap and water. This helps to clean the skin and reduce any potential irritation. Applying a cold compress or ice pack to the bite area can help alleviate any minor swelling, redness, or discomfort. Over-the-counter antihistamines or hydrocortisone cream may provide relief if itching or irritation persists.
To avoid bites, particularly from Asian Lady Beetles, prevention strategies are effective. Sealing cracks and openings around windows, doors, pipes, and utility wires in homes can prevent them from entering. Repairing damaged window and door screens is also important. If beetles are already indoors, gently sweeping or vacuuming them up is recommended over crushing them, as crushing can cause them to release a foul-smelling, yellowish fluid that can stain surfaces and irritate skin.