Top South African honeybee scientist, Mike Allsopp, has hailed the wonders of the Cape honeybee (Apis mellifera capensis), including its resistance to the most vicious pest that has devastated beekeeping in many parts of the world.
With World Bee Day on 20 May, Allsopp, lead honeybee researcher at the Agriculture Research Council (ARC), told beekeepers who work with Cape honeybees to remember it was “a very special honeybee”, the Kim Kardashian of the honeybee stakes.
The Cape honeybee is one of two indigenous species in South Africa, especially to the Fynbos biome. The other is the African honeybee, Apis mellifera scutellata.
Honeybee scientists have long been intrigued by the unique ability of the infertile female workers in Cape honeybee colonies to lay fertile eggs. They’re literally able to clone themselves, which usually occurs if the queen dies prematurely, in this way saving the colony from an almost certain end. This extremely rare phenomenon is known in the scientific world as Thelytokous parthenogenisis, and reportedly exists in about 1 in 1 000 animal species.
More recently, scientists have been investigating why the Cape honeybee has been so resilient in the face of attacks by the highly destructive varroa mite. Allsopp recalls the appearance of varroa in South Africa in 1995, saying there was “panic as never before”. The varroa mites gorge on a honeybee organ called the “fat body”, wiping out whole colonies. Beekeepers elsewhere in the world are forced to treat their hives with pesticides to control varroa, but the mite continues to cause mayhem.
In trying to understand why the Cape honeybee has managed to fend off varroa, Allsopp says scientists have observed further rare behaviour. The nurse bees routinely remove the wax cappings of the cells in which the larvae, or baby bees, develop. This is a massive chore, as each side of the comb can have up to 4 000 cells. If the nurse bees detect a problem they haul the larvae and dispose of it. Allsopp describes this unusual re-capping behaviour as ”checking under the hood”, citing it is “the number one factor in our bees to overcome Varroa and other serious diseases, such as American Foulbrood.”
But it’s the Cape honeybee’s capacity for “virgin births” that most fascinates scientists and the possibility of replicating this in other areas of agriculture.
In another discovery Allsopp says female worker bees in Cape honeybee colonies have the startling ability to produce the same pheromones as the queen.
The queen emits these pheromones largely to control and influence the smooth running of the colony. The workers mimic this and become pseudo-queens, receiving the royal reverence from other workers that is normally reserved for a real queen.
But there is a sinister side to the marvels of the Cape honeybee. The laying workers have the capacity to infiltrate and take over the hives of other indigenous honeybees, Scutellata, which occur outside the fynbos biome. Allsopp says, in this respect, the Cape honeybee is a “unique social parasite”, so much so it is listed as a bio-security threat in other parts of the world. People attempting to import the Cape honeybee into the United States can be charged with terrorism!
Both South Africa’s indigenous honeybee populations are robust in comparison with honeybees in the rest of the world where there are dire predictions about their long-term survival. Climate change, mono-cultural farming, the reckless use of pesticides, bee pests and diseases are causing significant losses of honeybees, traditionally regarded as apex pollinators.
The biggest challenge facing South African beekeepers is rapidly dwindling forage for their honeybees. This threatens the large-scale pollination service that beekeepers provide to local agriculture. Simply put, there won’t be enough managed bees to carry out this all-important job.
