The Swarming (of Ladybugs)

Every fall since we’ve been here we have experienced an increase of activity in “lady bugs”.  Early on it was so slight we barely noticed but in recent years it has been increasing in intensity.

Why Do They Bite?

My guess on this is that because all forms of ladybugs feed on aphids and the larval stage of several insects (thus earning them the status of beneficial garden insects) at this time of year these large concentrations of ladybugs cannot find enough to eat and turn to biting other creatures (like me) trying to obtain sustenance.

Actually the American Lady Bird beetle is not known to bite, but the Asian Ladybug does.  It is not toxic,  but not only is the bite painful, some people are allergic to it.

What’s the Difference?

Visually, the two are very similar and the untrained eye may be fooled. Both are similar in size (though the Asian beetles tend to be a bit larger than the American) and shape.  Both can be from yellow to red in color.  Both have black spots.

But there are some consistent differences that make it possible to tell them apart.

  1.  The Asian beetles have variable spots: anywhere from 0 to 20.  The American beetle has 9: 4 on each side and 1 spot just behind it’s head that is centered and bisected by the split in its elytron (wing covers).
  2. The Asian beetle has a black and white “head” with the black part forming an “M” or “W” shape.  The American beetle’s is primarily black.
  3. The Asian beetles are known to bite, the American beetle is not.
  4. The Asian beetle seeks shelter by invading our homes in fall, the American beetle is more reclusive and seeks shelter by clustering in sheltered locations outside.

Why Are Asian Beetles Here?

The Asian ladybugs were brought into the United States by the USDA and Forestry Commission to relieve the hardwood forests of many disease carrying aphids, mites, and scale insects.  But, the Asian species of beetle proved to be hardier and stronger than the American species.  The two compete for the same food sources, and the Asian species carries a parasitic fungus that kills other species of ladybugs.  Now the American Lady Bird Beetle is on the endangered species list as, once again, something imported is killing off the native species.

And from the looks of things lately, they’re gunning for us next!

About Doug

Jesus follower, writer, gardener, Sci-Fi fan, Beagle herder, occasional author, mountain man. My dogs think I'm a super-hero.

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