Killer Bee March Stops at State Line

So where the hell are the killer bees?

The much-hyped and seemingly inexorable invasion of Apis mellifera scutellatus appears to have screeched to a halt at the California-Arizona border.

The Africanized honeybees--which have camped out for months in Yuma--were expected to swarm into Southern California during the spring or summer. But the Colorado River has turned into something of a Rubicon that the hotheaded insects can’t seem to cross.

Experts have several hypotheses for their aborted progress: Because of a dry spring, the desert was inhospitable for safe passage, lacking the water, food and shelter to accommodate the crossing. Or perhaps the bees have run into one of their few natural predators, a mite that infests their honeycombs and consumes their larvae.

But most intriguing, some experts surmise that these tropical bees are genetically ill-equipped for more temperate climes and finally could be reaching the northward limits of an airborne journey that has stoked fear and titillation among Southern Californians and Hollywood filmmakers.

But even if the bees don’t try to cross into Southern California next spring, some authorities fear that they will sneak into the Central Valley when beekeepers from Arizona--where the Africanized bee has established itself--import bee colonies to pollinate crops in the spring.

So public agencies in Southern California remain on guard. Throughout the summer and spring, they set up “Bee Alert” booths at county fairs, instructed schoolchildren on the dangers of bees and trained firefighters in how to rescue victims of mass-stinging attacks.

The Orange County vector control office purchased protective bee suits and special spraying equipment and hired three people to do battle with the bees. “It’s like we’re all dressed up and have nowhere to go,” said Fred Beams.

In the meantime, the three bee fighters are assigned to rat patrol, he said.

Michael C. Pearson, the bee specialist with the Los Angeles County Department of Agriculture, said the bees’ delayed arrival “has bought us more time to get ready. We’re still very concerned the bees will come and pose a serious public health risk.”

Indeed, some officials fear that the public may feel that it was duped into thinking the sky was falling--and won’t be as cautious if and when the bees do arrive.

“We had (public education) momentum, and the fact that the bees haven’t gotten here yet has hurt our efforts,” said Bill Routhier, the San Diego-based bee specialist for the state Department of Agriculture. “It’s going to take a real effort to get that momentum going again.”

The hyper-defensive bees were unwittingly released in 1957 from a Brazilian laboratory where they were being studied for their tolerance to heat. They had been brought to Brazil from Africa a year earlier. The bees moved on to Central America and Mexico and arrived in Texas in 1990 and in Arizona in 1993.

When several colonies were trapped in Yuma last spring, public safety and agricultural experts sounded the alarm, saying the bees could arrive in California any day.

Despite that scenario’s failure to materialize, bee experts say that, with a wet winter, the bees might find the desert more hospitable for travel next spring.

The suspicion that the bee may have encountered its ecological limit intrigues scientists, who were not sure where that barrier would be.

“I think we can now scale back the maps on how far north we thought the bees would travel,” said Eric Mussen, a UC Davis Cooperative Extension apiculturist who has watched the bees’ progress with fascination.

“They might still get into San Diego or even the Los Angeles Basin, but I don’t think they’ll have the genetic energy” to thrive here, he said. “Their big push northward, and spreading out, has slowed down and may be running out.”

Indeed, the bee has not wrought the havoc in southern Texas that was initially feared. Beekeepers there have had little difficulty keeping their European honeybee colonies free of Africanized honeybee invaders. And the majority of wild bee swarms in southern Texas are still of the more mellow European-bee variety, despite expectations that the Africanized bee would by now have overtaken their more docile cousins.

The only fatality from an Africanized bee attack in the United States occurred in 1993 in Texas when an elderly man, already in poor health, was stung 100 times when trying to eradicate a colony with a torch.

In Texas, the bees have moved as far north as the suburbs of Houston; in Arizona, the bees have established themselves in Tucson and Phoenix. On Wednesday, Arizona recorded its 13th Africanized bee stinging attack on a person--a Tucson-area man who was mowing the bank of a ditch and upset a ground-level hive. Even as he ran for his life, he used a cellular phone to call for help, and is now recovering from 100 stings.

Given the slow advance of the bees, some officials wonder if their appearance in Yuma was an aberration--not part of some full frontal movement, but perhaps a colony that hitchhiked there on a truck. The fact that the bees have not regenerated in large numbers in Yuma suggests that they are struggling even there, scientists say.

The three discoveries of Africanized bees in California were the result of hitchhiking bees--once by truck, twice by ship. In July, the captain of a freighter entering Los Angeles Harbor from Guatemala notified authorities ahead of time that a colony of bees was on board. The bees were eradicated.

Routhier, the state’s bee expert, says he is more concerned that the bees might enter the state by piggybacking on commercial European bee colonies from Arizona.

Neither Arizona nor California regulates the movement of commercial bee colonies, and he said California is wide open to the unwitting shipment of Africanized bees here.

But Gene Brandi, a professional beekeeper in Los Banos who sits on the state’s Africanized honeybee advisory board and on the board of the California State Beekeepers Assn., dismisses that concern.

If the bees do not enter from Yuma or by way of the Central Valley, Routhier speculates that they may eventually work their way north along the Colorado River and cross into the irrigated farmlands of the Coachella Valley in Riverside County.

For now, authorities remain perplexed but vigilant.

“We were so sure they’d be here any day, we were frantic, trying to get the word out,” said Connie Valenzuela, deputy agricultural commissioner of Imperial County.

“Now, our message is, ‘We don’t know why they’re not here yet, or when they’ll get here, but you still need to know about them,’ ” she said.

Meanwhile, the two men hired by the Imperial County vector control office to exterminate Africanized bee colonies have been shifted to mosquito abatement.