From: Rod Rupert [mailto:[log in to unmask]]

 > Thanks for your comments on my mite situation here in Missouri.  I wanted to
 > provide some additional information, but not being sure if this was of
 > general interest, decided to send it to you directly instead of the list.

With Rod's permission, I have CC'd this reply to the list, along with my
comments and those of another commentator who adds an interesting insight.  I
think this problem and its resolution is of general interest and answers
questions in the readers' minds inspired by the earlier posts.  Moreover this
discussion blows a warning whistle and brings in an interesting mention of
formic acid...

 > The hive in question is the center hive of a 3 hive apiary I have in my back
 > yard.  This hive (# 2 in my recordkeeping scheme) was a runt all spring
 > chiefly because it swarmed twice.  One of those swarms was completely my
 > fault, which is a whole other story, and I am not sure what I could or
 > should have done to prevent the second.  The second swarm issued on May 30
 > and I was unable to recover it.  I inspected the hive on June 12  and found
 > no young brood but did find the queen with what appeared to be an egg
 > sticking out of her abdomen.  I ordered a new queen and split the hive with
 > a double screen and installed the new queen on June 17.  The queen I thought
 > had a problem turned out to be okay because during my inspection on June 27
 > I found brood in all stages both above and below the double screen.  I
 > killed the old queen anyway and reunited the hive bodies using the newspaper
 > method.  I never installed any honey supers on this hive.
 >
 > My next inspection was on July 17.  The upper body contained much capped
 > brood and the lower body the queen, eggs, and larva.  However, for the first
 > time in my 2 years of beekeeping, I saw mites on bees and a number of bees
 > with deformed wings.  This looked bad to me, so I installed 2 strips in each
 > hive body in the areas where there was brood.
 >
 > The following day I pulled the honey supers from the other two hives.  In
 > hive #1 I saw mites on drone brood that I pulled apart from the queen
 > excluder.  I didn't see any in hive #3 but did not check thoroughly.  After
 > extracting I put the empty supers back on hives #1 & 3 for the bees to
 > clean.
 >
 > On August 7 I removed the supers from hives #1 & 3 and inspected the brood
 > chambers.  Because of the obvious problems with mites in hive 2, and the
 > fact I had seen mites in the drone brood in hive #1, I reasoned I should go
 > ahead and treat these hives.  In preparation I had purchased a mite check
 > tray and a Beltsville screen insert from Brushy Mountain.  I installed the
 > tray in hive #1 and the screen insert in hive #3, and two Apistan strips in
 > the brood area of each hive.  After 4 hours I pulled the tray from hive #1
 > and the sticky board from beneath the screen insert from hive #3 and found
 > what I would estimate to be 200 mites or more on each.  Because of this I
 > reasoned treating at that time was the correct thing to do.  Several weeks
 > into the treatment on hive #2 I installed a screen insert and sticky board
 > which I would check occasionally.  As I noted, it was not possible to get an
 > accurate mite count because the ants were carrying them off.  I decided to
 > leave the screen insert on this hive all winter but close up the back during
 > cold weather.
 >
 > August 29 - Removed Apistan strips from hive #2.
 > October 2 - Removed Apistan strips from hives #1 & 3 and removed screen
 > insert from hive #3.
 > November 11 - Did the sticky board check as described in my earlier message.
 >
 > Recent Actions:
 >
 > On November 21 the bees in hive #2 had completed the second gallon of 2:1
 > syrup with Fumidil, so I did a quick inspection of the upper hive body.  Saw
 > no deformed bees and noted capped brood about to hatch on the center frames.
 > Population seemed more than adequate for the winter.  Two days ago with
 > temps in the 50's and some bees flying, I installed a sticky board under the
 > screen insert on hive #2.  Yesterday the weather was in the upper 60's with
 > bees flying and bringing in yellow pollen.  Noted orientation flights from
 > hive #2.  This morning, November 28, I removed the sticky board.  It had
 > been in about 46 hours.  I counted about 60 mites, all but a few appear
 > dead.
 >
 > The question remains: What is the significance of this level of mite fall at
 > this time of the year in this climate?  I am concerned that I may have
 > treated too early.  Last year I installed strips around Oct. 1 and removed
 > them at Thanksgiving, but I never tried to measure mite levels last year
 > either.  Given the indications I had this year in July and August, treating
 > then sure seemed like the correct thing to do.
 >
 > My first inspection of the year is usually in February.  Perhaps I will have
 > the answer then.
 >
 > Thanks for your comments.
 >
 > Rod
 >
 > BTW,  I had a request from the U. of Northern Iowa to send them my sticky
 > board with mites.  They wanted them for some DNA research they are doing on
 > the viruses that the mites carry in an effort to develop a biological
 > control.  They received them last week.

This gives us a detailed description of what happened and also clarifies some of
the questions raised from previous posts.  Obviously Rod is careful and
observant, so I doubt that his application was at fault, unless the product was
defective for some reason.

I can see nothing to indicate that the summer treatments should not have worked
and the writer seems to have followed all the instructions very carefully and
used good judgement as to timing.  The only flaw -- and it was justified and
very minor -- was the slight offset in timing of the treatments of adjacent
hives.  Frankly, I think that it could not begin to account for the current
level of infestation.

Going back to our previous discussions, that leaves re-infestation from outside
or Apistan (r) resistant mites.

Blane White wrote me about that when I sent him Rod's note, and I quote in full
with his permission:

 > From: Blane White [mailto:[log in to unmask]]

 > I will offer one little piece of the picture that I left out of my
 > original post.  This season there has been a very large increase in
 > fluvalinate ( Apistan ) resistant varroa in the US.  I know here in MN
 > that very very few commercial beekeepers are still getting varroa
 > control at all with Apistan.  In many cases many colonies have died
 > after treatment with Apistan this fall before the beekeeper got back
 > to them and realized that the Apistan did not work.  This fluvalinate
 > resistance has also been showing up in colonies belonging to small
 > beekeepers and they are reporting high varroa populations after
 > Apistan treatment or colony death with symptoms of varroa.  In short
 > given the situation here in the US by far the most likely conclusion
 > is that the varroa in those hives are resistant to varroa and get an
 > alternate treatment in there as quickly as possible to save them.
 > They could be past saving but one will never know unless one tries.
 >
 > On another related topic:
 > Some colonies seem to tolerate much higher varroa populations than
 > others and remain healthy and productive.  There are likely many
 > factors involved but some stocks appear to be much more resistant to
 > the viruses that varroa vector and that contributes to this toughness.
 >  I have successfully wintered colonies here in St Paul outdoors with
 > fairly high varroa loads - note I can afford to not treat with Apistan
 > and have been using drone brood removal to try to keep colonies alive.
 >  I have had colonies die from varroa but have also had some survive
 > pretty high mite loads it has been interesting trying to learn how a
 > small beekeeper can live with varroa without using the so called hard
 > chemical treatments.  Now I am not apposed to chemical treatment per
 > se but am somewhat concerned about residue of treatments in wax so I
 > will use formic acid next spring as it is now legally available here
 > now.  I don't have numbers of mites in hives etc just observations
 > with my few colonies and know I can keep them alive and productive but
 > actually focus much of my management on managing varroa instead of the
 > bees so it is not reasonable on a larger scale but we have to start
 > learning somewhere.  I am looking for an IPM approach to the varroa
 > problem.
 > FWIW
 > blane
 > Blane White
 > MN Dept of Agriculture
 > [log in to unmask]

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