The reason some dogs don’t do well with an invisible fence relates to pain levels as well as fear levels. A low-fear, low-pain dog like a retriever, either golden or Labrador, can sometimes just run through them. I knew one family whose golden retriever would bound through the perimeter on his way out of the yard but then refuse to come through it on the way back. He didn’t want to get shocked. Apparently he didn’t mind getting shocked when he was making his Great Escape, but getting a shock just to come home again wasn’t worth it.
It was a huge nuisance, because there was one family down the street who was terrified of that dog, even though he’d never done anything bad to them. Naturally that was the one house he’d always make a beeline for whenever he was done with his travels. He’d plop himself down on their doorstep and just lie there waiting for his owners to come get him and take him home. Probably he’d noticed that his owners always seemed to show up the fastest when he landed at the scared family’s house. That was true, of course, because the instant the scared family saw the dog they’d start frantically calling the owners every five seconds -- and naturally the owners would race over to retrieve the dog the minute they got the call, because they knew how upset the scared family was. Until the owners arrived, the scared family would be locked up inside their house, too terrified to come out. Naturally the owners lived in fear of having this happen sometime when they weren’t home. What if there was an emergency and the scared family was trapped inside their house because the dog had busted through the invisible fence again?
I heard about another dog, a little Jack Russell terrier, who would get through the fence just because his fellow-dog, another retriever, could go through it. The retriever would sail through unscathed, and the Jack Russell would lower himself to the ground and stare at the place where he knew he’d get the shock. Finally he’d bolt. The lady who told me about him said, “He’d decide to take the hit.” I’m sure if that dog had lived alone, or at least in a house whose other dog wasn’t a retriever, he would have stayed put. But he wasn’t going to let his pal take off without him.
Those are the problems you can have with dogs who are low-fear (or low-pain). They’re unusual, but they do happen. The problems that can crop up with a high-fear dog are more difficult to manage. I’ve never heard of a dog getting out-and-out traumatized by an invisible fence, but I’ve seen some come close. Some dogs will get so scared of the perimeter that they’ll refuse to ever go through it, whether the collar is on or off, and including when you put them on a leash to take them for a walk. You have to carry or drag them through the perimeter.
That’s not so horrible, but I also heard about a two-year-old collie who got so scared of her own yard that she lost her house-training and started pooping inside the house. If her owners would force her to go outside she’d just stand on the deck barking until her owners finally gave up and let her back in. Then she’d poop on the carpet.
These are all unusual cases. Most dogs live happily inside an invisible fence and don’t panic when you walk them through the perimeter on a leash. But even when an invisible fence works perfectly, you still have to keep on top of the situation. Although animal fears, like human fears, are permanent, animals will reality-test a fear that falls short of a phobia.
I know that happens with invisible fences. I talked to a woman who bought an aboveground invisible fence for her two young dogs. It worked like a charm, but remembering to put their collars on every morning was a pain. (She didn’t like the dogs to sleep in the collars at night, because one of them had sensitive skin and the metal prongs were rubbing it raw.) So she figured she’d be vigilant for a couple of months until the dogs took it for granted that they couldn’t leave the yard without getting a shock. Then she wouldn’t have to worry about whether one of the dogs got out of the house without the collar on. She said she based this on some story she read back in college about how B. F. Skinner once trained some sheep to stay inside a fence, then replaced the fence with a symbolic wire strung between posts. Supposedly the sheep never tried to get past the wire, even though they easily could have.
I don’t remember ever seeing that story in Dr. Skinner’s work myself, and I’d be surprised if that’s what he found. In my experience some animals don’t test fences, but others do. That lady turned out to have fence-testing dogs. At first everything seemed to be working out. The dogs never went near the boundaries, whether they were wearing their collars or not. They didn’t act like they associated the shocks with the collar, either, because every time she took their collars off to take them for a walk she’d have to pull them through the perimeter. They were scared of getting a shock whether they had the collars on or off.
So after a while she just stopped worrying about getting the collars on first thing in the morning. Big mistake. One morning she was sitting outside reading the newspaper when she noticed the dogs running a couple of feet up the hill beside her house, then coming back down again. They seemed to be doing this repeatedly, although she wasn’t paying close enough attention to be sure. She thought they were getting awfully close to the shock perimeter, but since she figured they’d been permanently conditioned like Dr. Skinner’s sheep, she didn’t worry about it.
The next thing she knew, both dogs were gone. They stayed away for hours and probably had a nice romp around the pond a little ways from her house. She’s been having problems with them ever since. As long as she has the collars on and the batteries are working, they stay home. But if she slips up -- either forgets to check the batteries or slacks off on putting the collars on in the morning -- it doesn’t take too long for the dogs to figure out they’re free.
I don’t know how they manage it, but it sounds like they’re doing their own doggie version of reality testing. The owner has observed that every time she forgets the collars for a few days the same sequence unfolds. First the dogs stay well within the invisible fence boundaries, collar or no collar. Then they start expanding the perimeter, going a little bit farther than the collar would let them go, but no farther. Then, not too long after that, they’re gone.
What she couldn’t figure out was, how do the dogs know it’s okay to expand the perimeter? They’re still acting scared when she takes them through the perimeter on a walk, so why do they test it on their own?
I think they are probably picking up signals a human can’t perceive. I’m guessing they get some kind of little vibration or early warning buzz from the receiver before they reach the spot where the warning sound beeps. They get a warning before the warning. Once the dogs stop perceiving the pre-warning sound or sensation, they start testing the boundaries.
The reason I think this is that the dogs never set off the warning beeps. That has to mean that somehow they know it’s safe to start pushing out the boundaries. If they were just sporadically testing from time to time, to see whether the perimeter was still there, they would set off beeps on days when their collars are on, which is most days.
However those two dogs are doing what they’re doing, the Mark Twain saying about the cat on a hot stove is true only as far as it goes. "She will never sit down on a hot lid again -- and that is well;” he said, “but also she will never sit down on a cold one anymore." That’s true only of a cat who got burned badly enough to be traumatized by the experience, or of a cat who didn’t get burned too badly but doesn’t have any good reason to sit on the stove apart from the fact that cats like to be up high. If the cat isn’t flat-out terrified of the stove, just leery, and if there’s a plate full of yummy meat sitting up there, I predict most cats are going to be back up on that stove.
Canada's Guide to Dogs
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as well as directly from the Author's website