Killer Bees: Appearance, Common Traits & Behavior

Killer bees have quite an interesting past. In 1956, a colony of African honeybees was imported to Brazil. Brazilian beekeepers wanted to increase honey production and decided they would cross-breed the African honeybees with the local bees.

This proved to be a mistake, as 26 African honeybee queens escaped and mated with swarms of European worker bees. This mistake created the Africanized honeybee, also known as the killer bee.

killer bee

How Big Are Killer Bees?

The name “killer bees” is enough to send shivers down most people’s spines as it sounds like a giant. The killer bee, however, isn’t much different from a regular honeybee. They’re actually smaller than European honeybees, measuring about ¾ of an inch.

What Do Killer Bees Look Like?

Killer bees are brownish in color and covered in fuzz. They also have a few black stripes; however, these aren’t as distinctive as those seen on wasps and hornets.

The killer bee has four clear wings which are attached to the thorax. Here, you will also find six legs. After the thorax comes the middle section, the abdomen, which is a bit larger than the thorax. The abdomen ends in the stinger.

The head of the killer bee is smaller than the body, although its eyes are large and bulbous. Killer bees have very efficient eyesight, which allows them to see ultraviolet rays. This means they can fly under darkness.

Why Are They Called Killer Bees?

Killer bees have been given their name from their hostile nature. They are extremely aggressive compared to other bee species. To understand why they’re so aggressive you’ll have to look at their relatives. Killer bees are a hybrid of European honeybees and African honeybees.

Honeybees, in general, are known to be quite aggressive, as they have to protect their hive. They do so by attacking the intruder with painful stings. The killer bee has taken this protective nature to a much higher level.

These bees will actually chase the intruder for up to half a mile. Sometimes they’ll do this without even being provoked.

Killer bees also have an incredible sense of threat. They can detect humans or animals from more than 50 feet away and mechanical equipment from a distance of up to 100 feet.

Why are they so aggressive? Where does this come from? Biochemists in Sao Paulo, Brazil have studied the brains of these fascinating bees.

They discovered two already known proteins called allatostatin and tachykinin. These are present in the bees’ brains at all times.

The biochemists did a test where they swung a leather ball next to the hive. They would then collect the killer bees which stuck to the ball as they attacked. The biochemists also collected a few of the bees still remaining in the hive to compare.

What they discovered was incredible. The bees that remained in the hive (unprovoked) only had the two regular proteins active in the brain.

The provoked bees, however, showed a third protein—neuropeptide. Neuropeptides are signaling molecules that influence activity in the body and brain.

In killer bees, this protein is what makes them more aggressive and easily provoked. The biochemists injected some of this protein into a few young honeybees. This resulted in the youngsters becoming aggressive, similar to the elder bees.

Neuropeptides aren’t only found in killer bees, though. In fact, other insects were found to have a certain amount as well. In other insects, however, the neuropeptides are used to regulate digestion and feeding, not aggression. Neuropeptides are also very common molecules present in humans.  

Are Killer Bees Dangerous?

Since their accidental beginnings in Brazil, killer bees have caused more than 1,000 deaths in the United States. When they attack, they most often do this in large swarms, meaning the victim will receive more stings.

When the killer bees detect a threat, they will respond very quickly. A swarm of drones will target the intruder, and nearly all the bees will go for the sting. Victims have reported being stung hundreds and even thousands of times.

Are they really that dangerous though? The simple answer to that question is no. Killer bees only become aggressive when they detect a threat to their hive.

If you’re out walking and you stumble upon one Africanized bee, chances are, it will just mind its own business.

Their venom also isn’t much different from that of regular European honeybees. The reason why their attacks can be deadly is due to the number of stings the victim receives.

Victims that are unable to run from the attack, such as elder, young, or disabled people, will have a more serious outcome.

People who already are allergic to bee venom will likely go into anaphylactic shock, which is a life-threatening allergic reaction. It requires an immediate dose of epinephrine, and in many cases, hospitalization.

As painful as the sting may be, the truth is it would normally take many stings to actually kill a human. If you’re a regular-sized adult with no allergies, it would take more than a thousand stings for the attack to be lethal.

There are also ways to reduce your reaction to the stings. Experts recommend scraping off the stingers instead of pulling them out. Pulling out a stinger, with your fingernails or tweezers, will only force more venom into your skin, worsening the reaction.

Living in Peace

Entomologists in Puerto Rico have been studying these bees since they were first detected in 1994. Studies have shown that the Puerto Rican Africanized honeybees have lost some of their aggressive nature over the years.

The studies also revealed that the killer bees attacked in fewer numbers were slower to sting, and did so less frequently. Puerto Rican beekeepers use local Africanized honeybees with no reports of aggressive behavior.

Entomologists suggest that the island environment is what makes the killer bees less aggressive. In Puerto Rico, there is an abundance of resources and fewer natural enemies to the bees, therefore, they become less defensive.

In other parts of the world, people aren’t as lucky though. Killer bees were first seen in the US, in southern Texas in 1990. They have since traveled, reaching Arizona in 1993 and California in 1995.

Listen to the Warnings

As scary as the killer bee may seem, they usually send out a warning before attacking. When they detect a person, or animal, closing in on the hive, the attackers might bump the intruder.

The bumping usually happens without stings, but in some instances they do sting. If you do not retreat after the warning, you most likely will be attacked.

What You Should Do If Faced With Aggressive Killer Bees

If you happen to come across aggressive killer bees, you may consider running for the closest water source. This method, however, won’t do you much good when dealing with these bees, as they’ll wait until you resurface. Here are a few tips to try:

Stay Calm and Quiet

Flailing your arms will only make the attack worse. The attacking bees will think you’re attacking them, or they may get stuck in your clothing or become trapped in places like the armpit.

Get Away

Killer bees will chase you down, and as we covered above, they do this for great distances. If you are being chased by a swarm, take shelter. Run for the car, house, or any other enclosed space where you can be sure the bees can’t follow.

In an unfortunate situation where shelter isn’t an option, your best bet is to try to outrun the attackers. Run as fast as possible and don’t stop until the bees stop chasing you.

Cover Your Head

Killer bees are known to go for one of the most vulnerable places—the face. The bees target the eyes, mouth, and nose; therefore, try to cover up the best you can. Use your jacket, shirt, or any other item you may have on you.

Never Kill the Bees

You may be feeling inclined to kill your attacker, but, this could prove to be a huge mistake. As an Africanized bee is killed, it releases an alarm scent. This scent will attract other bees from the hive, increasing the attack.

Where Do Killer Bees Live?

Africanized killer bees are considered an invasive bee species in the Americas. Since they were first established in Brazil, killer bees have spread south to Argentina and north into the southern states of the US.

Different from European honeybees, killer bees aren’t as picky when it comes to nesting sites. They will settle pretty much anywhere as long as the location is protected. You might find a nest underground, in rocky areas, and even around buildings.

Another interesting fact about killer bees is that they’re very quick to abandon a nest, unlike European honeybees. This happens often, especially if the nest is repeatedly disturbed or if there’s a shortage of food supplies.

Killer bees prefer a warm and humid environment and they also tend to choose nesting sites close to a water source.

African honeybees were brought to Brazil in the hopes of increasing the local honey production. Unfortunately, the Africanized honeybees actually produce less honey compared to their European co-workers.

They tend to store less food, or honey, in their hives. This is thought to be due to the fact that they’re native to an environment where food sources are available throughout the year.

Africanized honeybees also use more propolis when building their nests. Propolis, also known as bee-glue, has been known for centuries. Propolis was used as medicine in ancient societies in Egypt and Greece, due to its healing properties. The glue-like substance is produced by bees using substances they collect from plants, exudates, and buds.

Honeybees use propolis to build and repair their hives, the substance is hard and brittle in its natural form. When heated, propolis becomes wax-like and sticky. Africanized honeybees use propolis mainly to weatherproof their nest. Since these bees are native to tropical climates, they have adapted to survive unpredictable weather.

Nest Thieves

Since killer bees usually live in smaller colonies, they don’t require as much space as regular honeybees. Sometimes, though, they prefer to snatch an already thriving hive.

A small swarm of killer bees and their queen will sometimes land on the outside of a European honeybee nest. The worker bees from the Africanized colony will slowly introduce themselves to the new hive.

They will begin to exchange food and pheromones with the European worker bees—slowly ensuring their adaption into the colony.

After a while, the European queen is lost, most likely killed by the Africanized bees. The Africanized queen will then come in and take its place. The killer bees have now successfully taken over a European colony.

This is a behavior only seen in killer bees. European honeybees aren’t known to carry out these kinds of colony overtakes, but they often fall victim to it.

Killer Bee Colony Structure

Killer bees live in fairly small colonies; however, they do consist of the usual queen, drones, and worker bees. When the hive needs a new queen, worker bees will feed female larvae with royal jelly.

The first female larva to become a young adult will then become the new queen. She will then kill her queen sisters to eliminate any competition. Any unfertilized eggs will result in male bees, also known as drones.

Killer Bee Conservation Status

In North America, Africanized honeybees are much disliked by local beekeepers. This is due to the fact that they produce less honey, are more aggressive, and excessively leave their nest.

Most of the country’s apiaries are found in the south, where killer bees are found. If beekeepers decide not to continue their business, due to aggressive bees, it could affect the whole continent.

There are a couple of measures currently being taken to try and limit the amount of Africanized honeybees. The first is something called drone-flooding.

Drone-flooding involves trapping a large number of European honeybee drones before releasing a European queen. This reduces the chances of the European queen mating with the Africanized workers—which would only result in more killer bees.

Another thing beekeepers do to limit the number of killer bees is to requeen often. They will simply remove the queen and replace her with a European queen. This will ensure that the queen is always European, and that mating only occurs between European drones and queens.


The killer bee, also known as the Africanized honeybee, might be one of the most feared, but are they really so dangerous? What we have concluded is that killer bees earned their name from their aggressive nature, not for being ferocious killers.

Killer bees are smaller than regular European honeybees, however, they reproduce much faster. Africanized honeybees have almost the same venom as regular bees, so, unless you’re highly allergic, or are stung a great number of times, their sting won’t be lethal.

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