Stellenbosch – Nelson de la Querra, a commercial beekeeper, lifts the top off a beehive to reveal rows of neat wooden rectangular brood frames slotted into the bottom of the hive, like books on a shelf.
“Normally when a hive is healthy, I wouldn’t be able to do this without a bee veil,” said De la Querra, as he carefully grips a frame with his thumb and forefinger and lifts it out of the hive.
The frames contain the honey comb, where Cape honey bees store honey, pollen and their larvae.
“But look how lethargic these bees are. This is an indication that something is wrong with the colony.”
The hundreds of hexagonal wax cells in the frame De la Querra is holding are dark brown, almost black and have a sunken appearance.
In healthy hives the cells are light to dark brown.
He brings the frame to his face and gives it a sniff. It has a distinct rotting smell.
The many empty cells indicate the bee larvae are infected.
The hive, which De la Querra has placed far from other colonies at the Cape Honey Factory, a commercial beekeeping operation outside Stellenbosch, is infected with American Foulbrood (AFB), the world’s most debilitating disease for bees.
“These bees are sick. The only thing to do now is to kill them,” he said. “As a beekeeper you’re a nature lover, you don’t want to do this. But you have to, for the good of the other hives in the vicinity.”
Cape honey bees not only produce apicultural products like honey, beeswax and propolis (a resinous mixture with medical benefits), but also play a vital role in pollinating fruit trees, berry trees, sunflowers, squashes, watermelons and vegetables, and vegetables such as carrots, cabbage, broccoli and onions for seed production.
With butterflies, beetles and birds, they also help pollinate fynbos.
AFB was unknown in South Africa until the start of this century, with the first outbreaks reported in the Western Cape in 2009.
It seemed to die down, but last year made a serious comeback.
In a letter sent to members earlier this month, Mike Miles, the chairman of the South African Bee Industry Organisation, warned this outbreak was worse than that of 2009.
“The situation will continue becoming worse if serious measures in combating the disease are not carried out immediately,” he wrote.
According to De la Querra, between 10 and 15 percent of the hives in their operation are infected.
No cases of the disease have been reported outside the province, but Lynette Barnes, chairwoman of the Western Cape Bee Industry Association, fears it will spread if it is not contained.
Barnes said beekeepers who suspect their hives are infected should immediately contact the Department of Agriculture, Forestry and Fisheries which can test for the disease.
If hives are infected, the bees must be destroyed and the hive components sterilised, to stop it spreading further.
The health of Cape honey bees, said Barnes, directly affects the health of the agriculture in the province. And if AFB continues to grow and spread, the result could be devastating.
To kill the infected colony, De la Querra and a worker pour about 200ml of petrol into it and then wrap it with strong layers of plastic, entombing the bees.
The petrol fumes will kill the bees inside instantly, while other members of the swarm outside of the hive will die within a day or two with no home to return to.
“It is always sad to kill bees,” said De la Querra. “This is the first time since I have started beekeeping that I have had to do this.”
Later most of the hive will be burnt to kill all AFB spores.
Parts of the hive can be reused, he said, but only after being properly treated, for example by dipping it in heated paraffin wax or by irradiation.
Each hive killed and frame burnt means losses for beekeepers.
Honey that the hive would have produced, if it had been healthy, is lost. Less honey, in turn, means higher prices on supermarket shelves.
Sick hives cannot be rented to farmers who hire hives to pollinate crops.
Fruit farmers and seed producers in the province will also feel the effects of AFB. Deaths caused by AFB mean fewer bees to pollinate crops.
This may lead to significantly higher prices for “healthy” hives in spring, when farmers pay for beekeepers to place their hives on their land for pollination.
What is American Foulbrood?
AFB IS a debilitating bee disease found worldwide.
It is caused by bacteria which infect bee larvae\[dennis.cavernelis\] when they are very young. Adult bees are not affected. The larvae become infected when they\[dennis.cavernelis\] eat consume spores in their food and typically die after the spores germinate in their gut and start to multiply.
According to a report by the US Food and Drug Administration, in time the dead larvae dry out in their beeswax cells to form “hard, dark brown to black scales” which contain billions of spores.
Nurse bees and worker bees, going about their duties in the hive, spread the spores and the whole hive may soon become infected. The disease can spread between colonies by robber bees, which steal honey from weak infected hives and carry the spores with them to their healthy hives, or beekeepers using contaminated equipment.
AFB does not affect humans at all and honey from an infected hive is safe.
The Western Cape Bee Industry Association, with the Department of Agriculture, is embarking on a road show from February 26 to raise awareness about AFB. The campaign will visit 10 locations throughout the province. Call 021 865 2050 or e-mail [email protected] for more information.