Reviews of the Best Cat Repellents

Do Ultrasonic Cat Repellents Work?

Ultrasonic Cat repellent devices are the middle ground protection for your garden, they are more effective than powder or gel granules, but not as fully featured as water devices. Gardeners like them because they are affordable, effective and completely safe.

Some cat deterrents have multiple features, for example some water spray devices also have an ultrasonic feature build in, like the Guardener cat repeller. However what we are focusing on here are specifically ultrasonic devices, their features, advantages and exactly how they work.

ultrasonic cat repellers

ultrasonic cat repellers

So, Do Ultrasonic Cat Repellers Work?

Probably the first thing we should discuss is, do these gadgets actually work? Remembering that ultrasonic repellents are available for many different kinds of animal, this is a positive signal that they are valued by consumers. You can purchase ultrasonic repellents for dogs and insects, but interestingly not snakes. Here are some snake repellents if you are worried you cat may be takne by snakes! Anyway, back to cats; I know the first time I looked for a cat repellent it was to keep cats off my car at night, and the first thing I came across was cat powder. I sprinkled some around the car, but because the car is parked on concrete, it soon blew away and it was a pointless exercise. In the garden the same is true, albeit to a lesser extent, wind and rain are going to limit the effect of cat powder.

So after that failure, the next thing I heard about was ultrasonic devices to keep cats out of the garden. When I looked into it though, my first impression was that these were gadgets that probably didn’t work. I understood the theory, i.e. a noise that humans cannot hear, is annoying to cats, but there were a couple of concerns. Firstly, the device has to trigger, so it is reliant on a good movement detector. Secondly would it really annoy cats to the point they stopped coming around and scratching my car, or leaving cat poo in the garden?

As the device I found was fairly inexpensive, I bought it, put in a 9v battery, set it up on top of a small wall pointing at my car and tested it. There was a small red LED on the front so whenever it was triggered, you could tell. During testing, I could actually tell it was working because I would just hear the noise it was making, a high pitched tone, if I listened carefully. They say the tone is above human hearing, but I could hear it. Either the device was defective, or I had cat level hearing, who knows.

ultrasonic cat repellents

ultrasonic cat repellents

The end of this story is that yes, the ultrasonic did work, and I never came out to cat hairs on my cars roof or bonnet again. Of course it wasn’t the cat hairs that were bothering me, but the claw scratch marks they left as they tried to stop themselves sliding off my cars polished surface!

Even more surprising to me, was that even after my ultrasonic cat repeller stopped working because water got into it, the cats still never came back, bonus!

So that was my experience, but has there been any independent testing on ultrasonic cat repellers? Yes there has!

A study into the efficacy of ultrasonic cat deterrents found that they do work, and that the effect can discourage cats from returning increases the longer the device is used.  Unfortunately you have to pay to read the results of the testing, but I can summarize that in the 18 weeks test they involved well over 50 cats and concluded that ultrasonic device did reduce cat visits. They also advised that the effectiveness could be enhanced by carefully planning the location of the device to capture cat entry points.


Cat Repellent Videos

We have two videos of ultrasonic cat repellents scaring cats away. The first is a daytime example using the British CATWatch device, the second is a night-time example of a cat being scared off, using the Catstop device available in the USA.

In the video above you can see how quickly the cat runs off after meeting this ultrasonic unit; the cat was barely in the garden for 8 seconds.

Here’s the second video of an ultrasonic cat repeller scaring off a cat. You can see how quickly the cat reacts to the unpleasant sound emitted by the repeller. The device is located at the top left behind the cat, if you watch carefully you can see it being activated as a little LED lights up. Within 2 seconds the cat is gone. The device used in this test is the Catstop Ultrasonic.


There are other options for keeping cats away, common sense and easy to implement ideas, you can read about those in our how to keep stray cats away advice.