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Dr. Killer Bee 4 pages: | 1 | 2 | 3 | 4 |

How and why were the African bees brought to the Americas?

Image of Map
 
Africanized bees are currently found in five U.S. states: Texas, Arizona, New Mexico, Nevada, and California.

They were brought here in 1956 by Dr. Warwick Kerr, a pioneering geneticist. Brazil's honey industry was in terrible shape. The government came to him and asked him to breed a bee that would do well in Brazil's tropical environment. South Africa had very sophisticated beekeeping. They had good bees and made lots of money. Plus, the climate in Pretoria was almost identical to that of Brazil. So Kerr got some African bees and set up apiaries.

Now, what happened isn't exactly clear and there are some nice conspiracy theories, but some got away. At the time, nobody was aware of the severity of the stinging problem. They knew the African bees were a little more aggressive, but they thought they could breed that out of them. So Kerr and his colleagues set about the task of fixing and neutralizing the bees. They were successful and now Brazil is fourth in the world in honey production.

Dr. Kerr was vilified, but he did a tremendous service to the Brazilians. Brazilian beekeepers love these bees. They are a little bit testy, but the neighbors won't be able to steal them or the honey. These are the same bees we now have roaring around Tucson, Arizona.

What makes these bees such a problem in the United States?


Brazilian beekeepers love these bees. These are the same bees we now have roaring around Tucson, Arizona.

They "pioneer swarm." Like the pioneers who opened the frontier, the average guy was a little socially rougher and tougher than the guys who stayed in Boston and New York. The nastiest most defensive bees go north. Their wimpier colleagues wouldn't do well, because each time they'd arrive in a new place, predators would test them out, and the wimpy ones wouldn't make it. The nasty bees, well, the predators learn to leave them alone. It's like the Marines. The selection process favors the toughest and meanest and the most defensive.

What geographic or climatic factors are likely to keep the Africanized bees in check?

Photo of Bee Stinging
Bees stings can cause an allergic reaction in certain animals as well as humans.
 

As they get into more temperate climates, the Africanized bees don't deal as well with the long periods with no food. Our bees are adapted to get through a long winter. They swarm in late May- early June, and if they're lucky, they'll have enough time to store enough food for the winter. Our bees have evolved to swarm less often and early. They resist abandoning the parent nest.

In Africa, bees give up that nest any time of the year to avoid predators or lack of flowers. They can always find some flowers somewhere, so they can pick up and take off anytime. If they tried that in Salt Lake City, they are guaranteed not to make it through the winter.

Also, farther north, they'll run into very well adapted European honeybees. Where the Africanized bees are now, the European bees are kind of on the margins of where they're suited to live. Certainly, in the northeast and the Midwest, the European bees are wonderfully adapted and the Africanized bees coming in are really kind of marginal. In those places, the Africanized bees are outside the limits of where they do well. Where is the line? Everyone has a different opinion, but there will be lines.

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4 pages: | 1 | 2 | 3 | 4 |

Photos: Chedd-Angier; Justin O. Schmidt


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