Almost everyone has heard of "killer bees", but what they really are talking about are Africanized Honey Bees. Both names refer to the same bee. The term "killer bee" is a misnomer made famous from films coming out of Hollywood.
Africanized honey bees are hybrids of African honey bees brought to Brazil in 1956 and honey bees originally brought to North America by early European colonists. Because of the way Africanized honey bees have been portrayed in the movies, some people expect these bees to viciously look for victims to sting them to death. The chances of being killed by any honey bee is less than the odds of being hit by lightning.
To the untrained eye, an Africanized honey bees look like other honey bees, about 3/8" - 1/2" long. However, trained specialists can distinguish between Africanized honey bees and other honey bees.
All honey bee colonies are composed of three castes: a queen, several hundred drones, and from 30,000 to 50,000 workers. Because colonies are highly specialized, no individual bee, including the queen, is capable of living alone or establishing a new colony.
The worker bee, which flies from flower to flower, is the most familiar of the three castes. It measures about 3/8"- 1/2" long. Although the Africanized honey bee looks like our European honey bee, it can be differentiated by a laboratory examination and computer analysis. An identification method called FABIS (Fast Africanized Bee Identification System) is currently being used. First, a bee sample is taken and the wings are measured. Results are then compared with standard European bee wing measurements. If the results indicate a probable positive Africanized honey bee, a complete body part measuring analysis is conducted.
Both European and Africanized queens are responsible for reproduction in their colonies. Drones mate with the queens, while the workers, which are actually sterile females, collect nectar and pollen and defend the colony against attacks.
European and Africanized workers have barbed stingers. When either type of bee stings a human, it leaves both the stinger and tiny, attached venom sac. This causes the bee to die soon after. The venom of an Africanized Honey Bee is no more poisonous than that of their European counterparts.
Africanized Honey Bees are more defensive if provoked. The stinging response of Africanized Honey Bees is 10 times greater than that of European honey bees. Vibrations from motors, such as a power lawn mower or weed whacker, particularly seem to disturb them. When provoked, the bees will wander as far as a quarter mile from their nest to chase an intruder. However, individual Africanized Honey Bees on foraging trips for nectar and pollen are no more likely to sting than our European honey bees. Africanized honey bees tend to colonize large areas and swarm excessively. Also, the bees will leave the colony completely and move to a new location when conditions in the environment do not suit them - a special trait known as "absconding." Africanized honey bees may abscond on flights of several miles.
Africanized honey bees have spread through most of the Americas partly because of their tendency to move more frequently than other European honey bees. Their biggest move, however, crossing the Atlantic from Africa to Brazil, didn't happen by accident. Much controversy and a little mystery surrounds what exactly happened, but this much is clear: there was a man that helped them on that one.
By the 20th century, many people in the tropical zones of South America had developed a taste for honey and they imported European honey bees to establish on their farms. But these South American beekeepers found that the production of the European honey bee was not entirely satisfactory. The German, Spanish and Italian honey bees from colder and drier climates never adapted well to hot, wet and humid conditions of Brazil. To compensate, the tropical American beekeepers began investigating how they might breed a bee better suited to their special climate.
Some Brazilians thought the answer might be found in the tropical zone of Africa. They had seen reports of beekeepers in South Africa getting remarkable production from native honey bees. Some African beekeepers had imported European bees but they had not done well.
African peoples had been obtaining honey from the wild honey bees for many centuries, and while they knew how furious the insects could get, they had also developed ways to avoid attack.
In 1956 a Brazilian geneticist, Warwick Kerr, was asked by the Brazilian Agriculture Ministry if he could obtain some African honey bee queens and bring them back for breeding experiments. Kerr had devoted himself to studying Brazil's native stingless bees and was quite familiar with bee breeding and apiculture. Kerr believed he could utilize African bees to produce a new breed of honey bees, which would be less defensive than the wild African bees but which would produce more honey than European honey bees in Brazil's tropical setting.
By interbreeding the queens through artificial insemination with European drones, Kerr had produced a number of first generation hybrids. After several months of this activity, natural attrition reduced their stock of Africanized honey bees to just 29 bees and they were maintained in hive boxes equipped with queen excluders.
Queen excluders is a devise placed over the hive entrance with small holes. Because the queen and drones are larger than works, the queen bee is unable to leave the hive and therefore can't breed outside of the hive.
In October of 1957, according to Kerr, a local beekeeper wandered by, noticed the queen excluders and removed them. Such excluders are normally only used in the time before queens begin laying eggs and it is possible that the fellow was just trying to be helpful. As the story goes, the removal of the excluders accidentally released 26 Africanized honey bee queens with small swarms into the lush forest nearby. By the time Kerr learned of the accident, there was no way of figuring out where the bees had gone. He continued his work with the remaining Africanized honey bees and hybrid queens thinking that perhaps the escaped bees would either perish in the wild or mate with European honey bees and eventually lose their African characteristics. Wrong!
Within a few years, reports from surrounding rural areas of bees attacking farm animals and even humans. By the early 1960s, it was clear that a rapid expansion had occurred among feral bee colonies and that the Africanized honey bees were moving quickly into other parts of the country. Whereas European honey bee swarms might go only a few miles and look for an place to set up a new hive, Africanized honey bees often move 60 miles at a hop and build their nests. By the 1980s, they had reached Mexico. Africanized honey bees entered Southeastern Arizona in June 1993.