African bees to the rescue as colonies vanish?

The mystery of disappearing bees has scientists scrambling to find answers, farmers fearing the worst and environmentalists predicting its devastating effects. Pablo Macfadden investigates.
Issue Date: 11 May 2007

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A returning bee communicates with hive-mates by using specific movements that indicate the source of nectar.

The mystery of disappearing bees has scientists scrambling to find answers, farmers fearing the worst and environmentalists predicting its devastating effects. Pablo Macfadden investigates.

Across the United States and parts of Europe, bees are dying off and no one knows why. Hives have simply emptied. In America at least 24 states have recorded the phenomenon. Some reports say that half the country’s bee population has been wiped out in a matter of months. In some areas 90% of bees have disappeared. The Americans call it colony collapse disorder, or CCD. There are other names for it, like “vanishing bee syndrome”. CCD originally appeared in North America, where it appears to affect the introduced western honeybee.

Lately, European beekeepers claim to have experienced a similar phenomenon in Poland, Spain and Germany. Hives that have CCD often resemble ghost ships, with no adult bees and no signs of dead bees. Often food stores, both honey and pollen, are intact. Bee grubs are left abandoned. If CCD continues to wreak havoc across the US, its effects could be catastrophic. For example, orange and almond crops, which rely on bees for their pollination, would fail. Zac Browning, vice-president of the American Beekeeping Federation, is reported as saying “Every third bite we consume is dependent on a honeybee to pollinate that food source”. Various culprits While no one knows what causes CCD, scientists, beekeepers and even some conspiracy theorists have singled out one or two suspects. These include urban development, new pesticides, parasites, GM crops, an HIV/Aids-like disease and cellphone radiation.

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In the last few weeks the phenomenon of mass bee die-offs has begun to feature in the media. The news is so big that local bee researcher Dr Mike Allsop, of the Plant Protection Research Institute in Stellenbosch, received over 30 calls from journalists in a matter of days. Allsop keeps in contact with bee scientists in the US and has been monitoring the crisis closely. He believes that US bee populations have been in decline for decades, and is one of those scientists who thinks that chemicals might have something to do with it. “I think that bees have just had enough. In the US they use new pesticides and chemicals to deal with problems and don’t allow natural selection to take place.,” Allsop said. South African bees are more free-ranging and beekeepers are less likely to use chemicals, allowing natural selection to weed out the weaker colonies, he explained. Some researchers are pointing to a new class of pesticides called neonicotinoids that don’t kill the bees but instead hamper their ability to navigate and find their way back to their hives.
Another suspect is the varroa mite, also called the “vampire mite”. It has even been suggested that this blood-red parasite, which started infiltrating hives in the US in the 1980s, has introduced new bee viruses. The only problem is that the varroa mite has not been found in all the hives affected by CCD.

Bee stress
Another theory is that bees are dying off because they are simply stressed out. Beekeepers are increasingly taking on pollination contracts. They load beehives, one on top of the other, onto trucks and travel from orchard to orchard pollinating crops. It has become big business, and is now a bigger money-spinner than honey-making. In the US a single beehive can travel thousands of kilometres in a matter of months, all on the back of a truck. To keep the bees’ energy levels up, they are fed syrup and protein supplements.
Another explanation could be that these days bees are exposed to more pesticides and herbicides over a wider area. The genetically modified (GM) plant industry has also been singled out, with pesticides for GM crops possibly contributing to the spread of CCD. Again, some scientists say there is not enough evidence to blame GM crop pesticides. Another problem with this theory is that the majority of colonies that are dying in the US are nowhere near GM crops.
There is also a belief that plants poisonous to bees are the culprits, or that it might be new virus, like Aids in humans, that affects the bees’ immune system. Cellphones have also been fingered. There are thousands of articles on the Internet about the effects of cellphone radiation on bees. The belief is that electromagnetic waves released by cellphone towers could be disrupting the bees’ communication system, so they are unable to make their way back to their hives. Allsop says he has a problem with the theory. “I have searched for these articles, some of which have been printed in reputable newspapers. But they all quote a single German research study. I tracked down that study; it was published in 2003, cites no data and is actually just a proposal to conduct research on cellphones and bees,” he said.

Decline in SA wild bees In South Africa, there don’t appear to be the mass bee die-offs seen in the US. “Here, CCD is not on our radar. Our bees are happy and healthy,” said Allsop. However, Hans Blokker of the South African Bee Industry Organisation (SABIO) said that they weren’t sure if CCD was a problem, and were having urgent meetings about it. Organic bee farmer Tim Jackson, on the other hand, says that over the years he has noted a decline in the number of bees. “In Pretoria in 1995, we used to be able to catch between 16 and 18 wild bees in a day. We have only caught one this year. There are just no wild bees,” he explained. “ Interestingly, beekeepers around our cities have also noticed a dramatic drop in feral swarms in recent years.
To ensure new swarms of wild bees, the professional beekeepers have been travelling as far as the Lowveld and even KwaZulu-Natal to trap swarms. Thus an invasion of the Cape bee was blamed for the decline of the African bee on the Highveld, but this has never been proved,” he said.

But there might just be a saviour. The African bee, long demonised by the American press, could one day save the US farmer. While scientists are scrambling to find a cure for CCD, one researcher, Prof May ­Berenbaum of Cornell University, has ­proposed crossbreeding US honey bees with African bees. Africanised or “killer” bees, as they are known in the US, are considered more aggressive but they also appear to be resistant to CCD. But for ­American beekeepers to embrace the ­African bee would require a change in mindset. “In South Africa, probably between 10 and 12 people are killed by bees every year. In America, where they sue you if you spill a cup of coffee on them, there is no place for aggressive bees. But when the almond farmers are losing millions of dollars and facing collapse, they might just start ­considering Africanised bees,” said Allsop. Contact Hans Blocker at SABIO on (011) 678 2996 or fax (011) 476 6308. |fw