*Protocol to determine amount of mite immigration:*

The methodology for quantifying the number of mites invading a hive per
time period is relatively straightforward:

1.   At least six weeks in advance (I suggest mid May), choose one or more
strong, healthy hives to monitor.  In order to avoid inadvertently
selecting colonies that may have some sort of resistance to invasion, it
may be best to start with colonies that exhibit “normal” mite counts.

2.   Simultaneously apply at least two miticide treatments with different
modes of action, but that don’t disrupt the broodnest to any extent.  You
could start with an oxalic or formic treatment for quick knock down, but
also apply two time-release synthetic miticides (Apistan®, Checkmite II®,
or Apivar®) at the full label rate. Confirm that the used miticides are
efficacious against your mite population.

3.   Monitor the mite drop with stickyboards until it drops to zero per
day, and you feel confident that there are no mites left in the hive.  This
should occur by the first of July—the most reasonable time to start your
counts.  At this time, replace the miticide strips with fresh ones.

4.   From this point on, keep a stickyboard in the hive continuously,
rotating them to take regular mite counts (typically every 48 hours to
avoid accumulation of hive trash).  Since there were no mites left in the
hive, any mites on the stickyboards must have been carried in from
outside.  Record this data by day and mite count.  For consistency, plan on
taking an end-of-week count on the same day every week, and then total and
record the counts for that week.

5.  Continue these counts until colonies go dormant from the cold (winter
data would be of interest from where bees fly all year).  *Then please send
me the data and I’ll compile it in an article.*



*Protocol to detect a correlation between mite immigration with robbing:*

Limitation: must be performed in an area without late-summer nectar flows.

1.  In a yard, set up a number of hives having very low mite levels for
monitoring (so that they will not need treatment during the course of the
experiment).  Place the hives either on scales, or so as to allow easy
weighing.

2.  (Optional) Set one or more high-mite, honey-heavy colonies that you
expect to collapse in or near the same yard.  Or, restrict the apiary to
only the monitored hives, thereby measuring only mite immigration from
outside of the apiary.

3.  Take weekly alcohol wash counts (see note) and weights of the monitored
hives.

4.  Look for correlation between weight gain (as an indicator of robbing)
to the degree of increase in the mite counts.

Note: the two experiments could be combined (mite elimination, sticky
boards, and weighing), but dispense with the alcohol washes if you wish.
The stickyboard count data for mite immigration could then be plotted
against weight gain.  In either case, please collaborate with
[log in to unmask] for data sheets and the write up of the results.

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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