Why Bees Rob
Robbing occurs during a dearth of nectar. In Middle Tennessee, that can mean before the flowers begin blooming in the spring or it can mean in the height of summer, after the spring bloom and before the fall bloom. The bees have little to forage on and are drawn to the smell of honey in neighboring hives. If the bees can successfully challenge and overcome the guard bees, they will enter the hive and begin robbing. They will then return to their own hive to recruit more robbers. If not stopped, a frenzy of fighting, killing, and robbing will ensue. Soon you may have piles of dead bees and torn-up wax in front of a doomed hive.
How to Prevent Robbing Behavior
You can help to prevent robbing by leaving enough honey on all colonies to get them through the times in your area when flowers are not blooming. If you’ve harvested all of their honey, they will be starving and will be more likely to rob nearby hives. If you open the hives to feed them during a time of dearth, the smell of the sugary syrup or honey can incite robbing. At these times, it’s best to minimize your activity in the bee yard, getting into the hives only when absolutely necessary. Using a screen to reduce the entrances can help the guard bees by decreasing the area they must defend without restricting airflow through the hive in the summer.
Sometimes beekeepers mistake orientation flights or swarming for robbing. In orientation flights, the bees are young, fuzzy bees, and they are numerous but calm in their back-and-forth flights in front of the hive. Robber bees are older, slicker bees, having worn down the “fuzz,” and will behave in a frenzied manner, fighting with guard bees on the landing board and in front of the hive. When swarming, bees will be exiting rather than entering the hive and will flying enmass around the queen--not fighting with one another. Once they leave the hive, most of the activity will be high above the hive and not at the entrance. Swarming takes a matter of minutes whereas robbing can go on all day.
How to Stop Robbing Once It's Begun
If you see robbing in your bee yard, you’ll want to stop it immediately. Cover the hive with a wet sheet (this has worked well for me when I’ve had to do it). Reduce the entrance or screen it up completely for a day or two. Some people suggest taking the top cover off the stronger hive so that the bees will have to stay home and defend their own hive. This seems extreme and I have not tried it; however, I but might consider it if I couldn’t stop the behavior otherwise.
If you hive that has been robbed and left very weak, it may be best to combine it with another hive before winter.
Like other disasters in the apiary, robbing is easier to prevent than to stop. And at the risk of sounding like a broken record (if you follow my blog), it’s another good reason not to harvest so much honey from your bees that you have to feed them!