Here are our preliminary results:

By sugar shakes in ten yards, we obtained 45 mites from two to four hives, using about a cup of bees per hive.  All the sugar was dumped into a single bag per yard for later analysis (by dissolving the sugar in water).

At the time of the first test, we immediately placed two Apistan(r) strips into each of the same tested hives and inserted sticky boards with screens. The strips and boards were left in the hives a minimum of 24 hours and a maximum of about a week (see data).

The sugar gave us 49 mites and the boards returned 2384 mites for a ratio of about 49 mites dropped by Apistan for each mite found by sugar in the same hives, however one must consider that some individual hives and some yards returned zeros for both tests and therefore a simple ratio like 50:1 cannot be used. A quick glance reveals that the ratio varies from around 15:1 to infinity:1. Several hive groups that gave zero results from sugar shake subsequently yielded mites in the hundreds.

Here is the raw data:

Yard Name Sugar Shake Date Result (Mites) Sticky Board Inserted Board Pick up Date

Duration
(Days)

Result (Mites)
BCNE S28 0 S28 O5 7 0
BCSW S29 0 S29 O5 6 0
BCSE S29 0 S28 O5 7 13
Jahns' O5 3 O5 O11 6 0
Taylors' O5 0 O5 O11 6 1
Vanovers' O10 0 O10 O13 3 28
KadarE O6 0 O6 O13 7 235
KadarW O6 3 O6 O13 7 235
ButlerW O10 0 O10 O13 3 162
ButlerE O10 0 O10 O13 3 41
Pisco O11 0 O11 O13 2 204
Hainsworth O11 0 O11 O13 2 63
Dixon Bush O11 28 O11 O13 2 421
Wilson O10 4 O10 O11 1 288
Dixon O11 8 O10 O11 1 22
Beckwith's O12 5 O10 O12 2 72
Schlags Hill O10 0 O10 O12 2 213
Schlag CS O10 0 O10 O12 2 2
Rattai O12 1 O12 O13 1 381
Key: O13 is October 13, S29 is September 29

The work was done by our competent commercial beekeeping staff while going about their normal activities, following standard procedures. Our location is east and north of 51.1 N, 114.02 W or around halfway between Lethbridge and Edmonton, Alberta CANADA.

I would be interested in comments from scientists and extension people as well as beekeepers on what to think of this.

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