>>Don't forget the colonies that swarmed will have 3-4 weeks without 
laying queen until virgin is mated. During this time many mites will 
die and no new produced. Wouldn't surprise me if the parent colony is 
the one that loose most mites due to swarming. Mites only have flying 
field bees to live on for some time.

The time span from the last worker brood emergence to new eggs is about a week in my 
experience.  Mites get really concentrated on the last batch of brood from the departing 
queen's last eggs.  [Upwards of 75% of all the mites in a hive are in capped brood.]  This weakens the last emerging nurse bees.  Likewise, the majority of 
the phoretic mites attacks the first batch of brood from the new laying queen weakening 
them.

During the broodless period between the queens, a lot of the bees are idle or prepping 
cells for new eggs.  [There is no open brood to demand extra nutrition.]  Flying is much 
decreased compared to other colonies.  A lot of mites survive to do more damage.  
Literature seems to support this.

Waldemar

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