Subject: Re: Varroa questions from Ormond

From: [email-masked] (Adam Finkelstein)
Date: Fri, 22 Apr 1994 14:44:27 GMT

From: Aaron Morris <[email-masked]>
Subject:      Varroa answer

   In response to Rob Biddleman's query for Ormond Aebi about varroa, I
don't claim to be an expert, but I'll be glad to pass on what I gleaned
from a pamphlet distributed at our local beekeepers association
(unfortunately, I no longer have the pamphlet and I forget the source,
although I seem to recall that it's the producers of Apistan).  I'm
thrilled to pass on to Ormond what I know, in a small attempt to
return what he has passed on to me through his book, which I thoroughly
enjoyed!
   The life cycle of Varroa is such that varroa eggs and nymphs are
laid/hatch/wait for their host in individual cells in the comb.  When
bee pupae are capped, the adult varroa attach themselves and hence are
already on the emerging bee.  The mites have a preference for drone
cells, but I haven't a clue as to how they distinguish drone cells from
worker cells.
   The only treatment I have used is Apistan (something Ormond would
disdain).  I lost two hives this winter (even though I treated in the
fall) and dead mites were left all over the bottom boards.  I would
assume that once varroa decimate an area they will die off.
Unfortunately, it would take MASSIVE die offs on a large scale to
eradicate mites from an entire area.  Even if one's entire apiary is
wiped out, starting over from scratch gives no guarantee that there
won't be mites in hives in the next county over.  My question would be,
how do mites spread from hive to hive?  If the mites enter bees in the
cell, then how does a mite-less hive pick up the first mite?  The best
guess I can take at this one is drifting, but that's just a SWAG.
   So, I've written what I know and have ended with a question.  I hope
this will help, or at least lead to a more boisterous discussion.

-- 
===============================================================================
Adam Finkelstein  VDACS Apiary Inspector 116 Reservoir St Harrisonburg VA 22801
703-433-1006 (V)   703-434-5607 (Fax)   703-564-4394 (Pager)
[email-masked]    [email-masked]        |Bees To Please|
================================================================================

---

From: [email-masked] (Adam Finkelstein)
Date: Fri, 22 Apr 1994 14:46:04 GMT

Date:         Wed, 20 Apr 1994 08:53:00 -0700
Sender: Discussion of Bee Biology <[email-masked]>
From: "Paul van Westendorp 576-5600 Fax: 576-5652"              <[email-masked]>
Subject:      Re: Varroa answer

    Aaron Morris' "Varroa Answer" speculates on the way a mite-less colony
    gets infested.  Here in British Columbia, we have witnessed a progressive
    spread of Varroa from the most southern areas close to the US border
    northward.  Due to BC's topography marked by mountain ranges running
    north-south, Varroa has been following the valley floors where bees are
    kept, and where bees are being transported.  We have seen the typical
    'leaps & bounds' phenomenon of finding incidental Varroa infestations in
    apiaries that by themselves are pretty isolated (from other bee
    populations) but are always close to the highway.  Clear proof of
    infested bees escaping from trucks moving colonies from southern BC to
    the far north.

    The other form of spread is more localized but rapid nonetheless, which
    can only be explained through drifting and drone visitations.  I
    commented sometime ago on the distance of flight of bees, and referred to
    research done by Tibor Szabo in the early eighties.  Drones with free
    access to other colonies, coupled with their 'high motivation' (ie. sex
    drive) and physical ability to fly fast and far, are overwhelming likely
    playing a critical role as vectors of Varroa.

    Your question about how Varroa distinguishes between a drone cell/larva
    and a worker cell/larva is intriquing.  I have often wandered about that
    also, but perhaps some chemical or pheremonal cues may play an important
    role.

    Paul van Westendorp
    Provincial Apiculturist
    BC Ministry of Agriculture
        Fisheries & Food
    17720 - 57th Avenue
    Surrey, B.C.
    V3S 4P9  CANADA

---

From: [email-masked] (Adam Finkelstein)
Date: Fri, 22 Apr 1994 14:44:27 GMT

---

From: [email-masked] (Adam Finkelstein)
Date: Fri, 22 Apr 1994 14:46:04 GMT

Paul van Westendorp
    Provincial Apiculturist