How long do Varroa mites live when off hosts?

Discussion in 'Pests and Diseases' started by efmesch, Jul 7, 2012.

  1. efmesch

    efmesch Active Member

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    Ran a small scale observaation on Varroa mites from one of my hives.
    I was taking off honey for extraction and found some unemerged drone cells where they shouldn't have been. I decided to see if these drones were infested with mites and opened the cells and extracted the larvae/pupae one by one. Not all were infested, but there were several which convinced me that I was starating to get a varroa buildup that needs attention. I ntend to try my fogger with food grade mineral oil --if I can get it to work. If not, I'll probably use check-mite.
    At any rate, I decided to collect several mites from the cells and see how long they could live in an empty vial without hosts to feed on.
    P1030479.jpg
    Here's one of them. The vials were sealed with a small wad of cotton.
    I confess that I didn't run this observation as if it was a real scientific experiment, (I was busy with the extracting and associated activities too, plus company visiting) but did manage to follow them for two days. After 24 hours about half of them were still alive. After 48 hours they were all dead. Sorry that I didn't make exact counts nor run hourly checks, but take it for whatever it's worth. Incidentally, the light smear marks on the glass are from the mites--I assume their waste products, the vial was new and totally clean before the mites were put in.
     
  2. PerryBee

    PerryBee New Member

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    Thanks Efmesch, I just learned something! :thumbsup:
     

  3. Omie

    Omie New Member

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    Ah, but were these fully adult mites, or mites that were attached to drone larvae and possibly still maturing?
    I would have done the experiment on fully adult mites that were found on adult bees or wandering in the hive, not mites inside drone cells. Adult mites might have more mature extoskeletons, which might enable them to survive longer after having emerged from the drone cell 'mite nursery' area. Mites that are still maturing inside a damp cell might have more porous skins, which would be more vulnerable to drying out if placed in a vial before being fully adult. Just a thought!
     
  4. efmesch

    efmesch Active Member

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    Omie, your thoughts are definitely valid and in a really proper experiment they would have been accounted for. As to the mites I collected, they seemed fully mature. I didn't go into a description of my collecting them but I would add that they looked fully mature with regard to size, color and activity.
    Many of them managed to escape from being collected as, while I got my tools lined up (thin paint brush and tweezers), they ran off and hid in empty cells around the comb.
    As a behavioral observation I would add that this dispersion behavior is probably part of what quickly turns a hive into an infested mess and enables them to move from one bee to another.
    But I repeat, these are only observations, not experiments.
     
  5. Eddy Honey

    Eddy Honey New Member

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    efmesch,

    Thank you for sharing the results of your experiment and for taking the time to conduct it in the middle of a very busy time as you described.
    We now know that mites attached to hosts can't live more than 48 hours if they become detached, information I didn't know 5 minutes ago.

    Thanks again
     
  6. PerryBee

    PerryBee New Member

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  7. efmesch

    efmesch Active Member

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    Great pictures! I wish my camera would be able to take shots like that.
    In the 11th picture I believe that the white, round, small mite is a male. I came across a few like that but when mature, the males too are brown.