shb and swarms

[max2]

Not sure if this is a common occurrence or not.
I have been aware and I have seen it in my own yard  that a swarm, often  only small or a modest size, is leaving a hive if SHB  numbers increase.
Often these swarms don't fly off, indeed they tend to hang around on the hive they are leaving.
I assume that the reason can be found in the fact that the swarm contains  a physogastric queen.
She is not capable of flying.
In some cases these swarms may join another hive close by. In some cases I guess they simply perish. Sad.
In our case this activity is most common in mid summer when we have a lot of rain...plenty of rain, plenty of soil moisture...soil moisture =more SHB.

The behaviour is very different to the movements of swarms with a virgin queen. They often tend to return to the hive they came from.

Seen this swarm behaviour?

[Ben Framed]

I have been aware and I have seen it in my own yard  that a swarm, often  only small or a modest size, is leaving a hive if SHB  numbers increase.

I have noticed that after a swarm a good healthy hive will sometimes be more prone to SHB once the hive splits in the Spring. I suppose the number of bees missing give the SHB more opportunity to take advantage of the recent drastic decline of bees of the weakened swarmed hive... Natures way I suppose.. The strong survive, the weak.......

Phillip