How do varroa mites harm honey bee colonies? Several answers are possible.
- By transferring viruses between bees and brood.
- By increasing the susceptibility of bees to diseases.
- By directly destroying the food stores.
- By reducing the lifespan of the workers.
- By altering the quality of the food produced by the nurse bees.
- By causing varroosis, which progressively weakens the colony.
Show answer
Correct answers: 1 + 2 + 4 + 5 + 6.
By transferring viruses, increasing susceptibility to diseases, reducing the lifespan of the workers, altering the food produced by the nurse bees and causing varroosis.
Why?
Varroa harms bees on several levels. By feeding on the larvae, the pupae and the adult bees, it causes injuries, disrupts development and can transmit viruses, in particular the deformed wing virus.
On the other hand, it does not directly destroy the food stores of the colony. This weakening can reduce the colony’s capacity to forage, rear brood and overwinter, but it is not a direct destruction of the stores.
What to understand
Varroa destructor is not limited to taking food from the bee. It affects in particular the fat body, a tissue important for immunity, metabolism and longevity. Parasitised bees may emerge lighter, less robust and live for a shorter time.
When the young bees are weakened, their role as nurse bees can also be disrupted. The production and the quality of the brood food can suffer from this, with possible consequences for the rearing of the subsequent brood.
Key points
Varroosis is a progressive weakening of the colony, not just the presence of visible mites. The combined effects of the parasitism, the viruses and the fall in vitality explain why a poorly controlled infestation can lead to the collapse of a colony.