Taking the agricultural sting out of `killer' bees. US and Mexico are crossbreeding the insects to soften their impact

In a program they hope will thwart the northward movement of ``killer'' bee swarms, the United States and Mexico have joined forces to genetically control them. The Isthmus of Tehuantepec, the narrowest strip of land in Mexico stretching from the Pacific Ocean to the Gulf of Mexico, has been designated as the ``bee regulated zone.'' In this 100-square-mile area, an attempt is being made to stymie the spread of the killer bee so that scientists can learn more about how to minimize its impact.

According to many entomologists, growers, and beekeepers, the bees - which are hard to manage, produce less honey, and are poor pollinators - could adversely affect the agriculture and beekeeping industries in both countries if they are not slowed down or stopped.

Sam Lewis, an almond grower in Chico, Calif., says that if the killer bees spread into the US their impact will be ``unbelievable.'' The impact Mr. Lewis refers to is the havoc the bees could wreak on the $20 billion-a-year fruit and vegetable crops and the $150 million to $200 million-a-year beekeeping industry if they bring their undesirable traits into the country. Although beekeeping is a relatively small industry in the US, crops like alfalfa, almonds, melons, and other fruits and vegetables depend on bees for pollination. Many experts say the bees could impede this process.

Nicknamed killer bees because of their aggressive traits, the insects are a strain of honey bee from Africa brought to Brazil in 1956 by an entomologist who wanted to develop a hardier bee.

Since last September both the Mexican Ministry of Agriculture and Water Resources (SARH) and the US Department of Agriculture (USDA) joined efforts in funding an $8.75 million three-year program on the isthmus.

The objective, says Dr. Thomas Rinderer, laboratory director of the USDA's honeybee breeding, genetics, and physiology lab, is not to build a barrier to the bees' progression. ``It's to modify the population in that area so that whatever comes north is highly Europeanized.''

At present the program is concentrating its efforts on two control areas into which the bees have moved since May - one on the Pacific Coast and another on the Gulf Coast. The chief aim is to genetically dilute Africanized bees (European or wild bees crossbred with African bees). Africanized male bees are trapped; then, European males are flooded into the area to mate with Africanized queens.

Another control method is to induce Africanized bees to colonize in traps baited with sexual attractants. Every few months the traps are checked. The bees are then killed if they are found to be Africanized.

In addition, an extensive information program educates the Mexican public and beekeepers about the killer bees through animated TV spots and illustrated brochures. A bounty system encourages program personnel to find and bring samples of Africanized bees to the lab. Several Mexican state governments have also established a quarantine system for beekeepers so they will not move their bees to new areas.

At this stage it is too early to determine if the project is working, but many entomologists are confident it will succeed. ``We have a tremendous chance with this program. I'm very much convinced it will work, provided the government doesn't give up on it,'' says Alfred Dietz, an entomology professor at the University of Georgia in Athens.

But others, including Dr. Orley Taylor Jr., a professor of entomology at the University of Kansas in Lawrence, disagree. ``In order to make anything like this work, first of all you've got to have the technology, second, you've got to have the money, thirdly you've got to have the personnel, and fourthly you've got to have the infrastructure ... They [the US/Mexico program] don't have anything.''

Taylor says that trying to Europeanize the bees in the Rio Grande Valley of southeast Texas would be a more successful approach because their population densities would be lower, the bees would be approaching their climatic limit, and mountains provide natural barriers on two sides.

If the Africanized bees became dominant, beekeepers, who use little protective clothing now, would have to wear beesuits and keep the bee hives in isolated areas far from people or livestock. Their insurance rates would rise, growers would have to pay more to have their crops pollinated, and the price of produce would increase, say experts.

``We need to convince the people in power that we have a problem here and that we need to do something about it. What we're affecting is our food supply and the price of the food as well as the adverse impact of people being stung by bees,'' almond grower Lewis says.