The short answer

An ultrasonic or high-frequency deterrent can interrupt a dog mid-bark, and some dogs react strongly to it. Many react a little or not at all, the effect tends to fade as a dog gets used to the sound, and it barely carries through walls or glass. Used as an interrupter alongside training, it can help. As a cure on its own, it usually disappoints.

What a deterrent actually does

A deterrent is an interrupter. An unexpected, unpleasant sound makes the dog stop for a moment to work out what it was. That pause is the useful part: it is a gap you can reward, call the dog away in, or use to deal with whatever it was barking at.

What the sound does not do is change the reason for the barking. Dogs bark to alert, to ask for something, out of boredom, frustration or fear, and when they are left alone. A sound that interrupts every bark the same way does nothing about any of those, so on its own it teaches the dog very little.

What the research says

There is not much of it. We could not find a controlled study that measured whether consumer anti-bark devices reduce barking over weeks. What exists tests how dogs react to ultrasonic sound in the moment, and it points the same way: reactions vary a lot, and loudness matters.

  • Blackshaw and colleagues (1990) tested ultrasonic units, a flashing light and a compressed-air alarm on dogs 1 metre away. In the first experiment, with ultrasonic units at 60 to 75 dB, no device repelled all 15 dogs, though several reacted badly to two of the units and to the alarm. In the second, a unit putting out about 120 dB, far louder than a phone speaker can play, produced an immediate reaction in 13 of 14 dogs: nine aversive, two apprehensive, two that just pricked their ears.
  • Moxon, Allison and England (2010) exposed guide dogs to an ultrasonic pest repeller (29 dogs) and a device meant to deter young people (24 dogs). The dogs noticed both, but their behaviour was not adversely affected. Noticing a sound is not the same as being deterred by it.

Full references are under Sources. Neither study tested a bark-triggered device, and neither tells you what will happen with your dog. They are a fair warning against any product that promises a result.

Why dogs get used to them

Habituation is one of the most basic kinds of learning: a sound that keeps happening and never leads to anything stops getting a reaction. A deterrent that startles a dog on Monday can be background noise by the end of the week, especially if nothing else changes.

Varying the sound slows this down, which is why DogQuiet rotates between several. But variety only buys time. What makes the difference is what happens in the pause: a calm “quiet”, a reward for stopping, removing the trigger. Without that, the dog learns to wait the sound out.

Why they don’t work through walls

High-frequency sound is fragile. Walls, closed windows and double glazing absorb or reflect almost all of it, and even open air soaks up high frequencies faster than low ones. On top of that, every sound weakens as it spreads out with distance, and a phone speaker does not start out very loud.

So the sound needs a clear, fairly short path to the dog: same room, or outdoors and in view. In our own tests with a phone at full volume, outdoors and pointed at the dog, the useful range was about 15 metres. Through a wall it is close to zero.

Barking travels the other way much better, because it is loud and lower-pitched. That is why a phone can hear a neighbour’s dog through a wall that its deterrent cannot get through. For that situation a bark diary is the more useful tool.

Ultrasonic, or just high-pitched?

“Ultrasonic” means above human hearing. Dogs hear roughly 67 Hz to 45 kHz, and people roughly 64 Hz to 23 kHz, with the top end falling as we age. Those ranges come from a compilation of hearing studies by veterinary neuroscientist George Strain at Louisiana State University.

Phone speakers cannot play true ultrasound well, so phone deterrents, including DogQuiet’s whistles, mostly sit between 15 and 19 kHz: the very top of human hearing. Most adults will not hear a 17 kHz tone. Children and teenagers often will, and so will other animals: on the same compilation, cats hear to about 64 kHz, guinea pigs to about 50 kHz and rabbits to about 42 kHz. Think about who else is in the house.

When a deterrent is the wrong tool

  • Fear or anxiety. A dog barking because it is frightened needs to feel safer, not to hear another unpleasant sound.
  • Being left alone. Barking that starts when you leave is often distress about being alone. That is worth raising with a vet or a qualified behaviourist.
  • Pain or illness. New or unusual barking, especially in an older dog, is a reason to see a vet.
  • Boredom. A dog with too little exercise or too little to do will keep finding reasons to bark.

How to use one well

  • Use the pause. Reward the quiet that follows, or calmly call your dog away.
  • Watch your dog. If it hides, trembles, tucks its tail or seems scared, stop using the deterrent.
  • Keep a clear line of sight. Same room, or outdoors in view, and point the speaker at the dog.
  • Vary the sound so it does not become background noise.
  • Mind the household. Children and other pets may hear what you cannot.
  • Keep a record. When your dog barks, at what and for how long tells you more than any sound will.

That is the thinking behind DogQuiet. It answers a bark within about a second, stops when the barking stops, can rotate sounds, and keeps a journal of every episode so you can see what is actually changing.

Sources

  1. Blackshaw, J. K., Cook, G. E., Harding, P., Day, C., Bates, W., Rose, J. and Bramham, D. (1990).Aversive responses of dogs to ultrasonic, sonic and flashing light units. Applied Animal Behaviour Science 25(1-2), 1-8. doi:10.1016/0168-1591(90)90064-K
  2. Moxon, R., Allison, A. and England, G. C. W. (2010).Effect of ultrasonic devices on the distraction behaviour of guide dogs. International Journal of Orientation & Mobility (now Vision Rehabilitation International) 3(1), 27-37. doi:10.21307/ijom-2010-003
  3. Strain, G. M. How well do dogs and other animals hear? Louisiana State University School of Veterinary Medicine. Compiled from Fay (1988) and Heffner (1983), among others. lsu.edu/vetmed/deafness/hearingrange.php