Why are my bees so aggressive? In beekeeping, beekeepers are usually satisfied with pat answers because of the simplicity, but in reality nothing is usually that simple. One of the most common pat answers to aggressive behavior in honey bees this time of year is, “they finally have a home and brood to protect”, was this not true several months ago? Aggression in honey bees can be attributed to several different factors, environment, state or conditions within the colony or genetics. Genetics can be difficult to diagnose and is usually done through a process of elimination, meaning it is not environment or colony conditions. The (first and most important) factor with genetics is knowing where the gene pool of bees you have, came from, and staying away from known areas of the country that exhibit Africanized honey bee characteristics!

The simple remedy to genetic problems of any kind is to recognized the problem early on and change the genetics, (requeen).

Environmental issues and colony conditions are going to overlap somewhat because the environment can affect the colony both positively and negatively. Most conditions within the colony that cause aggression are usually observable, if you know what to look for, disease, swarm conditions, queen issues, poor or no ventilation, robbing, predation, and just shear number of bees being greater at this time gives the beekeeper more attention than desired.

Environmental conditions that can cause aggression are heat, cold, rain, high humidity, skunks, disturbances such as mowing and other yard work in to close a proximity to the colony or work being done at the wrong time.

Aggression is a stress indicator in bees, there are passive and non-passive stress indicators in bees, while most of us are very familiar with the non-passive such as alarm pheromone, biting, stinging, the more passive stress indicators are, bearding, and bee’s lined up peering from between the top bars. Any passive condition can turn to an aggressive state if ignored!

Solution to the problem again is recognizing the problem or condition and solving it ASAP. Most often the problem this time of year would be the heat and heat stress associated with it. Colonies that are bearding need ventilation at different points, top, bottom and maybe even in the middle, replace the inner cover with a moving screen this expels a lot of unnecessary heat from the brood nest. Also the beekeeper should purchase some 3” Styrofoam and place on the top and all sides exposed to the sun for long periods of time. Timely adding boxes to avoid congestion are also advisable, expanding the brood area in order to spread out bees on the comb is helpful, but labor intensive. Practicing all types of beekeeping well in advance will make for a better beekeeping experience for the beekeeper, family and neighbors, maybe even the family pet.

There is a lot of hot weather ahead try some or all of these ideas and expect to see a happier honey bee and better working condition for you the beekeeper.

Do not forget Varroa!!!!


43655 State Route 162
Spencer, Ohio 44275

Phone: 440-647-2602