Hello,

I have used screened bottom board inserts above a migratory bottom board
to monitor varroa mite fall. They are constructed like the commercial
models available with a  removable tray which can be accessed from the
front or back of the hive.

Upon removing a tray for inspection I have observed an occasional bee or
two fly from the tray area. I caught one of these bees and it could have
been used as the model in a varroa treatment advertisement. The mites
were hitching a ride back home.

Some preliminary results on the Russian F1 queens( blue line) versus my
own low mite queens selected from commercial bee stock. Initially weekly
mite fall from all the hives was less about 1 mite/day. After the Russian
bees emerged mite fall decreased to less than .3 mites/day and has
remained at that level. Mite fall from my own stock has steadily
increased to 5 mites/day.

Best Wishes
Dennis Murrell
Casper, WY