Varroa mite reinvasion?

[Chris B]

I have an interesting situation in one apiary. Forking out drone brood revealed a heavy varroa infestation in most colonies which I must now deal with. The colonies are not suffering (yet) and last autumn they were as clean as any other apiaries after Apiguard treatment. What is different about this apiary? My only clue is another nearby beekeeper who has also mentioned his bees are a bit shabby..
Does anyone have any similar story i.e. sudden jump in varroa population possibly explained by reinvasion via nearby collapsing colonies?

 

[Mike a]

I have an interesting situation in one apiary. Forking out drone brood revealed a heavy varroa infestation in most colonies which I must now deal with. The colonies are not suffering (yet) and last autumn they were as clean as any other apiaries after Apiguard treatment. What is different about this apiary? My only clue is another nearby beekeeper who has also mentioned his bees are a bit shabby..
Does anyone have any similar story i.e. sudden jump in varroa population possibly explained by reinvasion via nearby collapsing colonies?

An experienced beek friend warned of this happening after our long freezing winter (although compared to some other european countries our winter was shorts and t-shirt weather for them). He went on to say there will be a huge problem towards the middle of June onwards after several mite brood cycles useless beeks keep hitting them hard and use a range of different methods as part of their IPM before the main flow.

His suggestions
Icing sugar - pointless waste of time suggested using flour instead ? I don't see what difference this would make...
Drone culling
Thymol
Grease patties
Shook swarm if heavy infestation and other treatments not working.

 

[BobsBees]

Chris B,
Did you treat your bees with Oxalic acid over the winter, by any chance?
Bob

 

[Chris B]

Hi Bob,
yes I do, but I've done no varroa checks between autumn Apiguard and now.