About all those skunks and Racoons mentioned 
I solved that problem with high voltage.
I bought from a farm supply a system normally used for  livestock that 
supplies juice to a wire that is strung around a selected  area.I have the good 
fortune of having hydro nearby but there are solar versions  available for remote 
yards.
My wife actually heard one creature's yelp as they payed their visit. No  
more problems.
By the way, the tickle one gets is almost like that from a sparkplug wire  on 
a car.
 
Just an interesting observation:  I had two  3 inch screws just  above the 
entrance on either edge of the chamber acting as posts for the wire to  be wound 
around  with the wire strung from hive to hive.  The  bees immediately saw 
this as a foreign object and started to  deposit   propolis all around the screw 
where it entered the wood so  much so that it ran down the box to the bottom 
board and the buildup on some was  over three sixteenths of an inch.
They seemed to gather there and wiggle and waggle alot. Quite the  conference 
they were having.
 
Walter
Ontario

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