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.
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