Vibrating bees

[Fannbee]

I have about 100 or so bees on the front of my slatted rack moving up and down like they are doing a two step.  All behinds are pointing up and their heads are pointing down to the ground. 

What could this be?

[Jerrymac]

It's called wash boarding

Were they flapping their wings? That could be they were cooling the hive.

Here is something on washboarding

http://esa.confex.com/esa/2003/techprogram/paper_11018.htm

[Fannbee]

Well my wife did say they appeared to be cleaning the front of the hive.  No flapping of wings.

Thanks

[Michael Bush]

It's called washboarding.  I think it's just a line dance.