Hello Roni & All,

>  What would cause this to happen?

The problem can happen with caught swarms placed in new homes also. The
problem originates (my opinion) from a queen which is able to fly. She has
either been held long enough in a cage (since caged from the mating nuc) or
simply has not been mated.

I hand release certain queens and when properly mated and not caged long the
queens quickly start looking for a place to lay eggs. queens like yours will
fly from the cage or comb. Fly far and at times package bees will follow.

For years I used to rub the inside of new equipment used to hive swarms and
packages with leaves from a Peach tree. The practice was taught me by my 90+
year young mentor when I was a young teen. I run a small orchard and the
bees almost always will swarm to the Peach tree.

An alternate method is to cut a piece of old queen excluder ( or the new
plastic excluders which are reasonable) and cover the entrance for a few
days.  A frame of drawn comb can help.  Some beeks stick the whole package
in a bucket of water and pour into the hive. Others spray with syrup. Most
install at night or late evening.

Extremely rare both would leave but bees do not always read the bee books
and do what the books say the bees are supposed to do.

bob

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