Reasons for Aggressive Honey Bees
Why are your beehives suddenly aggressive? There are several situations than can affect the defensiveness of your beehives. Let’s investigate some of the circumstances that can change the mood of your honey bee colony.
Being stung is one of the less attractive parts of beekeeping. Why do bees sting? In general, stinging occurs when the bees feel provoked. As a beekeeper gains experience, he/she learns to gauge the mood of the hive.
Aggressive Bees in Your Apiary
Honey bees are a rule as not aggressive-they are defensive. This characteristic of honey bees is one reason we are able to work with them with a minimum of fuss.
Usually, they will not attack unless they feel threatened or feel a need to defend their hive. This is defense not offense.
However, terminology aside – I don’t see any reason to “split hairs”, the fact is that angry (or defensive) stinging bees are no fun – no matter what you want to call them.
Hive inspections are more difficult with 50 angry bees bounding off the front of your veil. And, you do not want to get chased away every time you are within 50 feet of a hive.
Top Reasons for Very Defensive Bees
There are many conditions that affect the level of aggression in your colonies. External and internal factors play a role. Some of the issues related to defensive beehives can be controlled by the beekeeper – some can not.
- hot humid weather
- a nectar dearth
- a queenless beehive
- genetic profile of bees
- colonies with large populations
- aggressiveness due to bee robbing
- predators bothering the hive
- not using a bee smoker properly
- clumsy beekeeper
- high varroa mite levels
- end of the season defensiveness
- alarm pheromones on your bee suit
- Africanization genetics
Hot Weather = Cranky Bees
The sultry days of late summer do nothing to improve the mood of my honey bees. I can’t really blame them. The hot, humid “air you can wear” doesn’t make me very happy either.
This is an important time of year as the workers are trying to ripen honey. They are also collecting water and working to ventilate the beehive and control internal temperatures.
Healthy colonies are often large at this time of year and that makes the work even harder. Really hot weather = grumpy bees.
Nectar Dearth Stresses Colonies
Most regions will experience a nectar dearth at some time during the warm months. A dearth (lack of abundant nectar/pollen) may last for a few days or several weeks. It hits my area in mid-late Summer.
This lack of incoming food creates stress in the colony. The queen bee may stop laying eggs and if the food shortage continues – drone bees may be evicted to save on resources. Colonies are known to be more aggressive during times of food shortages.
Queenless Hives are Known to Be Cranky
If you have been a beekeeper for any length of time, you know the importance of the role of the queen bee. She is the only layer or fertilized honey bee eggs but she serves another important function.
The queen emits special honey bee pheromones (chemical messengers) that hold the colony together as a family and helps regulate hive functions.
When those pheromones are missing, nervous, aggressive bees may be the result. The colony is in a frantic struggle as they know something is wrong.
Bee Genetics
Among the species of honey bees, they are a large number of breeds or races. These different types of honey bees vary in average aggression levels. Even within the specific breeds you will see variances in defensiveness.
Some genetic lines are more defensive than others. This is true in any type of livestock and honey bees are no exception.
The queen bee is responsible for 50% of the genetic material of the workers. The drones she mates with contribute the other 50%.
If your colony replaces their queen, the new bees will come from a different gene pool and could be more aggressive (or not).
Large Colonies Tend to Be More Aggressive
There will be exceptions of course but large bee colonies tend to be more defensive/aggressive than small colonies.
That sweet little starter you bought – package bees (10,000) in the Spring is now 40-60,000 strong. Large colonies of older bees are very protective and they have enough members to offer a strong response.
Robbing Causes Aggressive Behavior
Every sweet loving insect out there wants to get a taste of the honey stored in the hive. Of course, the colony cant stand by and let their winter survival food be taken. So they fight, often to the death to evict the intruders.
As the robbing bees (fighting) begins at the entrance, alarm pheromones are released. This alarm notifies the rest of the workers of a threat and is a call to action. All stingers on deck.
Unfortunately, while you may not be a robber –a hive that is being bothered by potential robbers gets rather testy at any disturbance.
Predators Attacks
Several animals can be predators of honey bee hives. When a bear attacks the hive, it is rather obvious. But smaller animals can cause bees to have a testy attitude too.
Skunks can be major predators of honey bee hives – especially hives that are set low on the ground. Each night the skunk stands in front of the hive and scratches.
When the guard bees come out to investigate, the skunk eats them. His thick fur protects him from bee stings.
However, the hive may still be grumpy the next time you come near the hive. A good ready to use hive stands.
Yellow Jackets prey on honey bees, large hornets and other insect pests can be a problem during the late season. This activity can put your hive on constant alert. Using yellow jacket traps earlier in the season may help – but it wont get rid of all of them.
Improper Use of Bee Smoker
Not using a bee smoker correctly can cause a hive to act angry. Cool, white smoke does not harm your bees. It distracts them from your inspection and helps mask alarm pheromones.
Failure to use a bee smoker or using hot, black smoke creates an aggressive response in your beehive.
Rough Treatment During Hive Inspections
Staying calm while performing hive inspections can be difficult-especially for new beekeepers. However, it is important to avoid quick movements and banging hive components together.
The fast hand movements and vibrations can cause the honey bee colony to become defensive and go into attack mode. Be gentle – move slowly.
Varroa Mites Play A Role In Hive Behavior
Of course, any hive that is unhealthy is prone to be cranky. When the the level of varroa mite infestation is high, the bee colony suffers.
This leads to having more mites per bee and the unbalanced population results in unhealthy bees. You may notice a stronger defensive response in hives with high mite infestations.
Late Season Bees Become Aggressive
The transition period from late Summer to early Fall, is the most common period for our bees to “get an attitude”. The bee colony knows that Winter is coming.
They sense the end of the foraging season. This can be especially frustrating to the beekeeper trying to do some Fall feeding of bee colonies. The bees don’t know you are trying to help.
After working hard all Summer to store food, giving it up without a fight is not an option. Winter survival of the colony depends on sufficient food stores.
A Dirty Bee Suit Trigger
Okay, do you stink? Well, I mean does your beekeeping suit stink? If your suit or beekeeping gloves have alarm pheromones or venom from previous stings this may trigger an aggressive response.
It is not only alarm pheromones to be concerned about. Bees are very sensitive to odors. Sweat or other strong smells can have a negative effect on the attitude of your hive.
Wash your bee suit occasionally. And, as I always tell the students in my online beekeeping class – “don’t go to the bee yard smelling like a bear.”
Strong smells and honey bees are not a good combination. It is also a good idea to avoid wearing dark colors in the apiary.
Africanized Honey Bee Genetics
Africanized bees (Apis mellifera scutellata) are present in many parts of the Southern United States. In most ways, they are very much like our everyday bees in the field.
However, colonies with these genetics are much more defensive than the European Honey Bees that we are accustomed to working.
The media has labeled them as “killer bees” due to the danger involved when a colony is alarmed.
Confirmation of African genetics requires the use of a lab, you can not identify them with the naked eye. If you live in an area with known African genetics, be vigilant in keeping docile queens in your hives.
Still, it is important to understand that even normally gentle colonies can become very defensive. Just because you have an angry hive – it does not mean they are killer bees.
Colony Temperament Changes Over Time
It is important to understand that the temperament of a honey bee colony can change at any time. This is why finding the best location for your beehive is so important.
Place hives far enough away from your house to have a buffer zone. The entertaining, docile new hive sitting beside your back door in April, may seem to be a monster in September.
This is a common beekeeping mistake that is easy to prevent.
How to Deal With Aggressive Honey Bees
Among the many factors that affect the temperament or aggressiveness of our honey bee colonies, some are seasonal. The hives will cool down once the weather cools. But what is the considerate beekeeper to do until the hives calm down?
- Inspect your colonies when the weather is nice – not the hottest part of the day
- Use your smoker with cool white smoke and be gentle
- Make and feed sugar water to your bees if they need it
- Control mite levels in your colonies – learn when to treat hives for mites
- Reduce the size of your hive entrances if you notice any robbing
- Requeen beehives that are constantly overly defensive
FAQs
Honey bees show varying levels of defensive behavior. But, the most common honey bee to show aggressiveness is the Africanized Honey Bee (aka Killer Bees).
Late Summer is the time of year when beekeepers most commonly experience aggression in their hives. Colony populations are high and the bees are very protective of their stored food.
Several factors inside and outside the hive contribute to aggression in honey bees. These include, bee genetics, colony size and health, availability of food and hive management.
Numerous workers buzzing loudly and clustering around the beekeepers head area as a sign of aggression. Also, bees that chase humans when they approach the hive from what use to be a safe distance.
Finally
The first bees brought to America (Black Honey Bees) were hearty insects but known to be defensive. Over time, bee breeders began to select for more desirable traits.
If your colony is well fed and healthy and not being disturbed by predators, they may just be experiencing the end of the season defensiveness.
Rarely a beekeeper may decide to destroy a dangerous colony and this can be a wise decision. However, don’t be too quick to make this decision.
A little patience may allow the colony to calm down when conditions approve. Or, you should consider giving them a different queen and hope that her genetics will produce a calmer bee.