No you are completely wrong , foxes are scavengers and opportunistic killers ......they will kill a pen of chickens because they are wild animals and tend to bury what they have killed to preserve it .......they often return to chicken pens the night after a kill to make sure the food source is still there ....of course generally it isn't .......as the people who have failed to pen in their chickens properly have cleared up .......instead of accepting this is how a wild animal works they blame the fox