Unfortunately, the science behind ultrasonic pest repellers is ultra-shaky. Seems like an attractive idea though, right? Just plug a charger-sized device emitting undetectable sound into the wall, wait about 2 weeks, then BAM, your garage oasis is insect and rodent free without the use of chemical pesticides or inhumane traps. Sounds great! Too bad these devices have never been proven to actually work. But let’s take a look at the theory anyway.

Ultrasonic sound waves have a frequency higher than what human ears can hear, but invading species can detect them. The sound is meant to irritate pesky critters and prevent them from making homes near the source of the noise. I’m pretty sure this is similar to how I feel about Montreal’s constant construction – in all fairness, I would move away too if I had the choice. But this only makes sense in theory. In actuality some animals seem to habituate to the noise, and others just don’t seem bothered at all.

Image by Cassandra Lee.

Some studies conducted in perfect laboratory conditions show that ultrasonic sound can be fatal to certain species by critically increasing their body temperature or causing audio-induced seizures. So the humane notion of pests simply scurrying out of your garage with a massive headache isn’t quite right either. But due to the variable nature of pest invasions, these findings have not been replicated in actual homes. Researchers using higher quality ultrasound generators have shown that sound can be effective at disrupting mating or eating habits of particular animals. These generators, however, are several grades above any device available for consumers which can’t replicate the complicated patterns of sound and turn out to be pretty much useless.

Additionally, the studies done on commercially available devices are very limited and often lack a control situation. Thus when some studies show that pest infestations do decrease, they have no way of proving that it was a result of the ultrasonic sound. For these reasons, researchers strongly advise against buying into these devices. There is simply not enough evidence. But this doesn’t stop companies selling these products from making claims. This device – one of many similar models available on Amazon – claims to use “safe & effective technology to extremely irritate rodents and insects thus causing them to run away from your home”. Well, they are definitely right about them being safe, safe for humans and pests alike: don’t be fooled.

“But Linda swears by these devices, she never gets mice”, you might say. Well it’s very possible Linda got very lucky. Pest control is messy and extremely variable between homes, so save yourself the $19.99 on Amazon and try some other old fashioned methods: like endlessly sealing up holes and shaking your fists angrily at the pesky critters.

@cassandranlee