Thursday, September 24, 2009

Multi-Colored Asian Lady Beetle

 The name of this little ladybug is a mouthful; to say the least. They are called Multi-Colored Asian Lady Beetle (Harmonia axyridis), or just Asian Beetle as many of us refer to them. They are native to Asia as the name suggests, and were brought to the United States in 1916 to help control Aphid populations in greenhouses. A few of these beetles escaped the greenhouses and found this new country much to their liking. So much so that they are now found throughout all of the United States and most of Southern Canada. On top of those that escaped confinement there were enterprising individuals who felt that our own native species just weren't doing their job adequately enough to suit them, so in their infinite wisdom they released these beetles in various locations all across the United States. In effect they succeeded in controlling the aphid populations, but they also made things very difficult on our native lady beetles, which just couldn't compete with a new, more aggressive interloper. Consequently many of our own lovely  ladies have disappeared in parts of their range and are severely declined in other areas. Not all ladybugs are created equal....Asian lady beetles amass in huge numbers in the fall and invade our homes, garages, and other structures, looking for a place to spend the cold winter months. Asian ladybugs also give off a musky sent when disturbed and can give a little nip when handled. Sometimes they will land on your arm and bite for no apparent reason, other than they feel like it.

Asian lady beetles are highly variable in color, ranging from orange, red, reddish-orange and even black with red splotches out in the western most part of their range. Sometimes they are spotted, but many are not. In Missouri these beetles have a white pronotum (thorax region) that contains four black spots, that vary from small to large, and can sometimes blend together to look like a "W" or "M".

Mating takes place at all times during the late spring and summer. I've seen larvae as late as September, feeding on aphids. The tiny larvae look like miniature alligators, they are voracious eaters and consume untold amounts of aphids, thrips, mites, moth and butterfly eggs and other soft bodied insects. It typically takes them a total of four instars(molts) to reach adulthood. In the last molt they will enter into a pupal stage. This pupa is an elongated dome shape attached to leaves by the spikey remains of the last molt clinging to one end. Once they reach adult size they may live up to 90 days, depending upon food sources available and temperatures. In Missouri there are probably two generations each year.

Newly Emerged Asian Lady Beetle

                                                               Asian Lady Beetle Larvae

                                                     Asian Lady Beetle Pupa

For many of us, a Ladybug is a Ladybug. I suppose in some ways this true, they certainly look similar. I can't say that I dislike these Asian Lady Beetles, they are serving a great purpose by ridding us of harmful aphids and other plant eating insects. I only wish it didn't come at such a high price for our lovely native ladies.

Im sure many of you have been reading about a worthwhile project that Cornell University is sponsoring. Cornell is famous for it's citizen scientist outreach projects. We are all familiar with the Great Backyard Bird Count, and Frog Watch. This newest project called "The Lost Ladybug Project" encourages individuals to explore their parks, natural areas, backyards and anywhere else that you are likely to find ladybugs. Camera in hand, photograph any all ladybugs you find. Take those pictures and upload them to Lost Ladybug Project. Give your best guess as to what species you think you've photographed. They compile this information and use it to determine how populations of individual species have changed, including their range, and numbers. It is truly a worthwhile project and fun for anyone who enjoys getting outside.


  1. Shelly I have seen lots of the 4th picture, just had no idea what they were. I am not looking forward to their visit this year. They get down my shirt and in my hair when we are outside and yes they do bite. I pray for cool days, cloudy days which keep them away. They seem to peak after the first frost if I remember right.

  2. It won't be long and they will be here in NWMO is great numbers, and yes it does seem to be right after the first frost. Sometimes we have them in such great numbers that the south side of my house looks like it is polka dotted. They hoard themselves into our window sills, and come into the house each time someone opens the door, then they end up in all the light fixtures. Little dead bodies cooked in the light fixtures is not exactly a welcoming sight to say the least.

  3. How do you control them? Just moved into a new house this winter, and every sunny day brings them out of the woodwork, all over the windows and into the rooms. I could vacuum twice a day everyday and still have ladybugs crawling and flying around. I spray around the windows and vacuum them up, but the next day, they are back!

  4. There really isn't a fool proof way to get rid of them. They are very persistent, especially in the fall when they are seeking shelter for the winter. Then again in the spring when they are leaving those shelters. Vacuuming is usually what is recommended and then returning them outside, but they just come back in again. Pesticides can be used, but many of them can be toxic to pets or to other insects that you may not want to kill. I'm not a big advocate for using pesticides. Truthfully these beetles may be just one of those things you have to put up with. Many people bemoan the fact that they have them, but I've not heard of one good remedy for getting rid of them. I get them by the 1000's too in the fall, and many of them make it into the house. Generally speaking though I don't see a lot of them throughout the winter. Lately I've been seeing a few that are coming out of their hideouts. Soon spring will be here and they will disappear out in the gardens where they belong. Thankfully.