https://bushfarms.com/beesnaturalcell.htm#whynaturalcellsWhy natural or smaller cells?
Varroa Life Cycle
Foundress enters the brood cell just before capping.
Lays one egg about every 30 hours.
First is male the rest are female.
Females have to reach maturity and mate to be viable and this takes 10.5 days from when the egg is laid.
Typical number of offspring in a worker cell with 21 day cycle (capped on day 9 and emerge 12 days later) is between one and two (1.5 +- 0.5) in a drone cell between three and four (3.5 +- 0.5). On small or natural cell the cycle is 19 days and the offspring are between none and one (0.5 +- 0.5)
During its time in the capped cell all of those Varroa, foundress and offspring, feed on the pupae weakening it and spreading viruses.
After emergence of the bee, the viable mites (the foundress mite and the one or two that made it to maturity and mated) go into their phoretic stage clinging to the bees and sucking their hemolymph like a tick, again spreading viruses and weakening the bees.
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How do smaller cells help?
Male survivorship
Less male mites survive: Reproduction of Varroa destructor in South African honey bees: does cell space influence Varroa male survivorship? Stephen J. MARTIN*, Per KRYGER
Shortened Pupation
A model of the mite parasite, Varroa destructor, on honeybees (Apis mellifera) to investigate parameters important to mite population growth. D Wilkinson, , G.C Smith
More chewing out of varroa
Small cell and natural cell beekeepers have noted more chewing out of Varroa when regressing their bees.
Pre and Post Capping Times and Varroa
8 hours shorter capping time halves the number of Varroa infesting a brood cell.
8 hours shorter post capping time halves the number of offspring of a Varroa in the brood cell.
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Accepted days for capping and Post Capping.(based on observing bees on 5.4 mm comb)
Capped 9 days after egg laid
Emerges 21 days after egg laid
