Nothing sweet about bees with basic killer instinct


January 02, 1994|By John D. Cox | John D. Cox,McClatchy News Service

SACRAMENTO, Calif. -- Any day now, certainly by spring, the inexorable northward march of the honeybee with the reputation of a killer will reach California.

The advance guard probably will cross the Colorado River near Yuma, Ariz., where they were spotted in September, and enter the agriculturally rich Imperial Valley.

As they move up through the state during the next few years, they are going to change the way millions of Californians think about bees.

No reason for panic, experts say, but make no mistake: This is one mean little buzzer.

The advice to the stung is to run like the dickens -- fast and far, or as quickly into a house or car or other enclosed space. If one has stung, thousands could be on the way.

"Their threat to society is from their extreme defensive behavior," said Norman Gary, an entomologist at the University of California, Davis, and an expert on the Africanized honeybee. "Notice I don't say aggressive behavior."

The distinction is lost, of course, to a person under their ferocious, swarming attack.

After all the hype and all the hope over the years, entomologists say the Africanized honeybee is as ornery as it was when the first queens escaped from the hives of an experimental Brazilian breeding site.

Africanized bees have killed more than 600 people in the hemisphere and countless animals.

Individual Africanized bees in the garden are no more of a menace than domestic European bees, scientists say.

The lethal difference is in the behavior of the swarm in proximity to the hive. Sensing their hive threatened, the Africanized bees attack with a ferocity unseen in European bees. They attack faster, in greater numbers, for longer periods and farther from the hive.

"The worst component is that these large populations spread out in the general area, up to one-quarter mile out from the hive," said Mr. Gary. "That is the great threat to people and animals -- this overactive defensive reaction," he said.

The whole population is the progeny of just 26 queens mistakenly released at a breeding project site outside Sao Paolo, Brazil, in 1957. Beekeeper Warwick Estavan Kerr was attempting to develop a more productive tropical honeybee, hoping to combine the productive characteristics of the African bees with the docile European bees.

"The guy was no crackpot," observed UC Davis entomologist Robert Page, a specialist in bee genetics. "He was working from basic, fundamental concepts of plant breeding that had been tried and proven since Luther Burbank."

Among geneticists, it's the proverbial case of crossing the cabbage and the radish, hoping to get the head of the cabbage and the root of the radish. "But what he ended up with was the root of the cabbage and the head of the radish," said Mr. Page.

The offspring of the escaped queens quickly produced a population that easily overtook the territories of European bees. Nothing -- not sophisticated genetic sciences or the most advanced management practices -- has stopped them.

Among the hopeful theories was the idea that as the insects advanced, their continual interbreeding with European bees would dilute the genetic strain, leading to a bee population that would be progressively more mellow. "That whole concept should be scrapped," said Mr. Gary.

Scientists are not sure why the Africanized bee is genetically so dominant. One theory holds that European bees were never well-established in the tropics, and the thriving Africanized populations overwhelmed the gene pool. Others suggest that natural selection is at work.

Advancing roughly 200 miles a year, scientists say, the bees will march straight up the state through the agricultural heartland of the Central Valley, likely devastating commercial beekeeping over time and interrupting the pollination of thousands of acres of crops.

"Africanized bees are going to spread throughout all of the areas for which that particular genotype is well adapted, and there's nothing we're going to be able to do about it," said Mr. Page.

Nobody knows for sure what the northern limits of their range will be -- how cold a winter these tropical immigrants can withstand -- but apparently nothing short of climate is going to stop them.

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