The most effective way to combat rats is with rat poison. However, if you don't want to kill the animals straight away, you have to rely on alternatives. One of these alternatives are ultrasonic devices that are said to be able to permanently drive away rats, mice and other rodents. Unfortunately, no general statement can be made as to whether this method actually works. Reason enough to take a closer look at rat control using ultrasound.
Ultrasonic waves
From a physical point of view, noises or tones are nothing more than mechanical vibrations that spread in waves. We humans cannot hear or perceive all of the sound waves that surround us every day. It really depends on the respective frequency or frequency range. The so-called ultrasonic waves move above the human hearing frequency range. They are imperceptible to us. However, things are completely different with certain animals. In this range, you are able to hear sounds from around 16 kilohertz (kHz). Just think of dogs and the famous dog whistle. The situation is very similar with rats, mice and other rodents such as martens. You hear these sounds and, depending on the volume and duration of the exposure, find them unpleasant, if not painful.
Principle
The theory is that rodents avoid a place that is exposed to ultrasound or leave as quickly as possible - precisely because they find the sounds extremely uncomfortable and dangerous. To combat rats or other unwanted rodents, all you have to do is set up a device that generates ultrasonic sounds either permanently or at certain intervals. In fact, a fairly large market has now been established for these special rat and mouse repellents. The devices are also used to keep martens away from parked vehicles. The animals themselves are not harmed. This will not permanently affect your hearing either. The aim is simply to create an atmosphere or a background noise in which the rodents definitely do not feel comfortable and do not want to stay.
Devices
Typically, these devices produce sounds in a frequency range of 40 to 42 kHz. The volume is around 120 decibels. For comparison: the usual noises in the apartment fluctuate around 45 decibels, traffic noise has an average of 75 decibels and a jackhammer in the immediate vicinity can reach up to 120 decibels. It has been proven that he alth problems occur in humans when exposed to continuous sound above 80 decibels. For animals that are usually more sensitive to hearing, even a lower value is likely to cause significant problems and drive them away. However, the rat repellers usually do not send a continuous tone, but rather individual tones at fixed or different intervals. With good devices, the frequency and volume can be adjusted individually. They are usually operated with rechargeable batteries or standard batteries. Also important: You can only provide sound to a certain area at a time. Depending on the version, this is often in the range of 250 square meters.
Operation
A so-called rat repellent can be used both inside a building and outdoors. It is best to place it in the area where traces of rats have been discovered. These traces can be either droppings left behind or gnawed clothing and leftover food. As a rule, the devices are used primarily in attics, cellars and sheds. It is important to know that ultrasonic waves cannot penetrate walls or other barriers. In case of doubt, several devices would have to be purchased. When using them outdoors, it is also important to ensure that they are weatherproof and, in particular, reliably protected from moisture.
Effect
What sounds logical and quite convincing in theory often turns out to be very problematic in practice. Anyone who looks at customer reviews of rat repellents on the Internet will quickly notice that extremes dominate. Some of the reviews are downright euphoric and report sensational success. The other large part, however, usually has the tenor that the effect is zero. So far, all that has been scientifically proven is that rodents perceive ultrasonic waves and, depending on the volume, find them unpleasant. However, there is no scientific evidence that rat and mouse repellents work. Experts strongly doubt the effect and point to factors that also play a role.
Getting used to it
Rats in particular can get used to the noise relatively quickly. Especially when the clever animals have realized that the sounds are unpleasant but do not pose any real danger, there is often no stopping them. In addition, rats, especially in larger cities, have long since become accustomed to frightening background noise, so even ultrasound may no longer frighten them.
Hunger
Another point could be that the animals are so starved that they simply ignore the noises when a treat or food at all beckons. So you are consciously taking a certain risk in order to survive.
Tip:
Before using electric rat repellents, it is essential to eliminate all possible food sources and loopholes. They are not interested in places where rats can neither find food nor sleep.
Problem
Finally, there is another problem with the devices. Dogs and cats can perceive ultrasound even over large distances. If you keep pets, the devices can quickly become unbearable torture for them and lead to massive behavioral problems. Even if the distributors succeed in controlling rats, you may pay a high price.
Alternatives
If you don't want to use poison when fighting rats, you can use some tried-and-tested home remedies. First of all, it is important to eliminate all possible food for the animals.to be sealed well – this particularly applies to garden waste. If you already have rats in your garden or house, a mixture of chlorinated lime and vinegar distributed in bowls can help. It has been proven that rats cannot stand the smell. The situation is very similar with turpentine. And a coat of lime mixed with iron vitriol is anything but inviting to the animals. However, these measures do not offer 100% protection.
