Out west where the moose run free they step over the fence and break the top wire. Some farmers now put an electric fence on the top rung only so the moose stop breaking the fence. I was hunting one day and a cow moose saw me, ran up to the fence then started running up and down it quite frantically. Finally she found a spot to crawl underneath the fence. Haven't seen anything quite so commical since.

Nothing is foolproof to a sufficiently talented fool.