The Problems with Underground or Invisible Fences

Periodically people ask my opinion on underground or invisible fences.  These are fences that rely on a cable laid in (or on) the ground and an electronic collar to keep a dog within a prescribed area.  When the dog gets too close to the cable, the collar will beep in warning.  If the dog continues, the collar will administer an electrostatic shock.  Generally, the boundary is initially marked with flags and the dog is gradually introduced to the fence.  Many people love their invisible fences but I don’t.  In fact, I don’t consider them to be a fence at all. 

Invisible fences:

• Don’t protect your dog from people or other animals coming into the yard and harming him.  If something poses a threat, your dog does not have an option to try to run away.

• Can cause or increase aggression and anxiety because the dog may associate the discomfort of the beep and/or correction with the people or dogs he sees passing by at the time.  If your usually cheerful, people loving dog is consistently corrected with a beep (a threat that he may be shocked) each time he trots towards the neighbors walking down the road, he may change his mind about the neighbors.

• Can cause fearful dogs be uncomfortable in their own yard.  Some dogs may be scared enough that they just won’t go out in the yard period; others may not be able to relax enough to go to the bathroom or simply enjoy the space.  Some dogs are noise sensitive and just the warning beep of the collar will make them nervous.  What’s the point of having a yard if your dog isn’t happy and comfortable there?

• Will not prevent your dog from breaking out if the stimuli is strong enough.  I have known many dogs that will happily run through a functioning invisible fence – they have learned that once they are through the shock will go away.  Once they get out, most dogs will not cross the barrier again to get back inside.  After they have learned that going through is an option, many dogs will break out over and over again. 

• Will fail when the battery gets low or the wire is damaged.  Many dogs learn that when the beep fails, the shock does too and they will be out and gone before you realize the battery is low.  If anything breaks the cable, your dog may be able to escape before you realize the fence is broken.   

Finally, that “harmless beep” really isn’t harmless.  To you, it’s a warning that your dog is getting too close to the boundary.  For him, it is a threat that he may be shocked.  Some studies have indicated that dogs may have a similar psychological response to the beep as to the actual shock itself and no wonder – the beep means the shock may be coming next.  Even for dogs who only ever get shocked once, the beep itself can be very aversive.