Last week, Scott Mathews, who lives in drought-besieged southern California, came home to a hive in turmoil. He writes:
I came home today . . . to discover a lot of bees in the air and what looks like combative bearding. [There are] clumps of bees falling from the top entrance and what looks like new piles of dead bees on the ground and a few dead on top of the hive. I only saw one battle occurring on the ground though.
Being new at beekeeping, Scott didn’t know if he was seeing a colony being taken over by another (usurpation), a swarm, or some other kind of attack. The next day, he continued his story with photos:
I have attached a few photos of my hive from this morning (the second day of the attack). . . . There was much more activity the evening before.
Initially there was a clump of bees about 6 inches wide and about 8 inches tall with clumps of bees falling off and re-coalescing at the top entrance. There were also small “battles” occurring on the ground which looked rather one-sided (6 to 1).
After sunset I went back to the hive and noticed that the main entrance (which is JUST over 3/8th inch high) was PACKED with dead bees. So the only open access to the hive is the top entrance which is an opening about 20% of the hive width and just over 3/8th inches high. The photos are the morning after I first noticed the situation and the attack seems to be continuing.
The hive is inside a fenced off area with 6-foot high fencing and is about 12 feet by 8 feet. The 4th side is a block wall. I have gates at both ends. The photos are taken about 7:30 A.M. in sunny Southern California.
In my opinion, this is a classic case of robbing honey bees. Robbers follow their sense of smell to locate sources of food. Air that is leaving the hive is laden with odors, including the aroma of honey. The robber bees congregate in areas where they detect the smell and repeatedly try to get in. Entrances, ventilation ports, space between boxes, cracks in the wood, and poorly fitting joints are all places where the scent can leak out.
Robbing gets worse in times of drought. Honey bees suddenly have a lot of time on their hands with nothing to do, so they are perfectly willing to steal nectar from another hive. The hive being raided tries to defend itself and fighting ensures. Dead bees are commonplace.
Because robbers can do a lot of damage in a short time, and because it can be difficult to stop once it starts, prevention is key. In my own apiary, I’ve had good success with reducing the entrances at the first sign of dearth (especially on smaller hives) and leaving them reduced until the autumn rains begin. Other beekeepers avoid opening hives as much as possible.
An invention called the “robbing screen” also works well. The robbing screen fits over the front of the hive and creates a new entrance that is not in line with the actual entrance. The hive scent drifts out of the conventional entrance and attracts the robbers while the bees living in the hive soon learn the location of the new entrance. Some robbing screens also have a metal plate around the new entrance to further reduce odors from that area of the hive. Any robbers that manage to find the new entrance can be handled by the colony because the number is small compared to the large mobs at the fragrant entrances.
Scott kindly labeled his images, so if you are not accustomed to robbing bees, the photos are quite instructive.
Thanks, Scott, for the share.