How does the Varroa mite reproduce? - briefly
Female Varroa mites enter a capped brood cell, lay a fertilized egg that develops into a daughter, and subsequently deposit several unfertilized eggs that become sons; the offspring mature and emerge with the emerging adult bee, continuing the cycle.
How does the Varroa mite reproduce? - in detail
Varroa destructor reproduces within honey‑bee brood cells, exploiting the developing pupa as a nutrient source. A mated female, known as a foundress, enters a capped cell shortly before the worker or drone larva is sealed. She deposits her egg on the ventral surface of the pupa, adjacent to the hemolymph flow.
The first egg is unfertilized and develops into a male. Subsequent eggs are fertilized, producing female offspring. The timing of egg laying follows a precise schedule: the male egg is laid within the first 12 hours after cell capping, while each female egg follows at intervals of about 30 hours. This staggered deposition ensures that the male reaches adulthood before the females, allowing mating to occur inside the same cell.
Mating takes place within the sealed cell. The adult male, which never leaves the cell, copulates with each emerging female before they exit. After mating, females attach to the pupa’s cuticle, feeding on hemolymph through a specialized mouthpart. They remain attached through the pupal stage, completing their development.
Upon emergence of the adult bee, the mature female mites hitch a ride on the newly emerged adult, dispersing to other brood cells or to adult bees in the colony. They can also engage in phoretic transfer, spending several days on adult workers before re-entering brood cells to start a new reproductive cycle.
Key points of the reproductive cycle:
- Foundress enters capped cell before sealing.
- First egg → unfertilized male; later eggs → fertilized females.
- Egg‑laying intervals: ~12 h for male, ~30 h for each female.
- Mating occurs within the sealed cell; male never leaves.
- Females feed on pupa hemolymph, develop, and emerge with the bee.
- Dispersal via phoresy on adult bees leads to colonization of new cells.
The entire process from cell entry to mite emergence typically spans 9–12 days for worker brood and 12–14 days for drone brood, reflecting the longer development time of drones. This precise synchronization with bee development enables Varroa populations to increase rapidly within a colony.