Thoraiya DyerPest Free II Ultrasonic Repellent – Drive Rodents Away By Laughing At Them
June 12th 2008 00:50
The Pest Free II Ultrasonic Rat and Mouse Repellent flashed across my humble TV screen the other day, and it got me to thinking. If ultrasound really was effective at driving rodent pests away, why isn’t it used in every warehouse and supermarket in the country?
Companies like Emblem Pest Services ( Really Long Link ) would be out of business by now if it was that simple. And yet there are plenty of these still living amongst us:
Can ultrasound drive rats mad? To them, it’s just like any normal sound, right? How do we know they don’t sing along with it like a malamute harmonising with an ambulance?
Well, let’s start at the beginning with a definition of ultrasound. Says SearchSecurity.com,
“Ultrasound is acoustic (sound) energy in the form of waves having a frequency above the human hearing range. The highest frequency that the human ear can detect is approximately 20 thousand cycles per second (20,000 Hz). This is where the sonic range ends, and where the ultrasonic range begins.”
Products like this one ( Really Long Link ) don’t specify either the frequency or the loudness of their broadcasts:
…they just give us Empty Reassurances. And here at Demented World, there’s nothing that makes us quiver with delight more than Empty Reassurances.
“The Pest Repeller Ultimate® II pumps out powerful ultrasonic frequencies inaudible to human ears but unavoidable to small pests like insects and rodents. Similar to a loud siren, the ultrasonic sound waves constantly fluctuate and pulsate on and off, making it impossible for pests to ignore the deterring sounds.”
More Empty Reassurances can be found on their Ultrasound Page ( Really Long Link ):
“Our ultrasonic pest control utilizes a high pressure ultrasonic sound that is only slightly audible to human ears. This pest repelling technique emits a disorienting pulse that startles and frightens away insects and rodents from your home or office.
Imagine a police siren and how the pounding rise and fall of the sound frequencies are impossible to ignore. Using a variable pulse generator, our ultimate pest repellers emit a range of fluctuating sound waves so pests don’t get accustomed to the sound. Your indoors are turned into a cacophony of deterring noises that ward off pests immediately.”
Imagine if repelling and disorienting police sirens drove humans away. They wouldn’t even need to get out of their cars to stop riots!
Then again, the poor police would travel about in little uninhabited bubbles of loneliness. Nobody would talk to them. We’d be too busy abandoning our homes, children, bank safes full of gold bars, etc.
Could it be that we don’t run away because we are capable of learning that a siren is harmless? And could it be that mice and rats are capable of figuring out the same thing? I mean, people listen to Insane Clown Posse, not to mention the speeches of George W Bush. Doesn’t that prove that you can accustom yourself to anything, no matter how hideous?
Limitations of ultrasonic devices can be found at Pestfree ( Really Long Link ):
“The Indoor Pest Repeller combines today's electronic technology with extensive pest behaviour research. the result is a compact device which can safely be used around children, pets and other electronic equipment.
Simply plug in switch on at the mains. Highly effective against Rats and Mice. Do NOT use in close proximity to pet Mice, Rats, Hamsters, Gerbils etc, as they will become very distressed by the ultrasonic waves. Cats and Dogs etc will be unaffected.
Ultrasonic sound cannot penetrate walls or other hard surfaces. Proper coverage for all rooms will require multiple units. Maximum effective coverage for each unit is approximately 50 square metres.”
I’m intrigued. Rodents will bolt in terror but dogs and cats will be fine, when the previous website mentioned the sound would be “slightly audible” to humans? If it’s slightly audible to humans, how can dogs and cats fail to hear it?
ISU has a handy reference here: Really Long Link , which shows the hearing ranges of humans compared to various animals.
The species we are concerned with:
Human: 64 – 23 000 Hz
Dog: 67 – 45 000 Hz
Cat: 45 – 64 000 Hz
Rat: 200 – 76 000 Hz
Mouse: 1000 – 91 000 Hz
So, blasting out a siren close to the upper limit of human hearing (23 kHz) is definitely going to be audible to a dog. If you wanted to target mice and rats, but not humans, dogs or cats, you’d need something above 64 kHz but below 76 kHz.
It’s possible. It could work.
There are also ultrasonic products designed to stop cats from killing birds in your garden. Note that canaries and cockatiels can only hear sounds in the 250-8000 Hz range. If you wanted to keep cats away but not birds, it seems like a simple enough thing to target the 23 to 64 kHz range.
So, the theory is sound (aaaaar har har).
But does it work in practice?
Laboratory studies would seem to back up the claims, for example this 1982 study ( Really Long Link ) by Shumake et al, where rats in little Perspex chambers were exposed to ultrasound:
“Three ultrasonic devices (20, 20-30, and 40 kHz) were tested for effectiveness in repelling Philippine rats (Rattus rattus mindanensis) under 3 sets of test conditions (i.e., plentiful vs. restricted food supply, native vs. immigrant rats, and continuous vs. discontinuous ultrasound).
Food consumption was significantly reduced for all devices under the plentiful-food condition.
With restricted food, only the 20-30- and 40-kHz devices reduced feeding.
Immigrant rats (animals preadapted to living adjacent to the ultrasound test chambers) showed a high avoidance of the new sound-chamber areas including the control (no ultrasound), making the test insensitive.
Native rats (animals preadapted [confined] to the chambers before exposure to the ultrasound devices) showed significant avoidance of food in 3 test chambers containing the ultrasound devices, especially the 20-kHz unit.”
Interesting. But how long do the rats stay away for?
Forever?
Not according to the British Columbian government in Canada ( Really Long Link ):
“There are several devices on the market that emit ultrasound waves to repel rodents. Although rodents will avoid the area initially, they apparently get used to the sound and learn that there is no harm associated with it. The repellers are expensive and seem to be effective only over small areas for a limited time.”
In 2002, the US Federal Trade Commission ( Really Long Link ) weighed in on the matter:
“According to the FTC's complaint, the respondents do not have a reasonable basis for claims that ultrasound will eliminate or repel pests, including rodents and many insects, from a user's home.
The complaint charges as false the respondents' claims that some PestContro devices drive away pests by altering the electromagnetic field of home wiring. In addition, the FTC alleges that the respondents have no basis for their claims that particular devices repel or eliminate pests in a space of a certain size (e.g., 2500 square feet) or that other products repel deer, racoons, skunks, or similar animals from a yard.”
Paghat’s Garden is wonderfully scathing ( Really Long Link ) and a good, fun read:
“Well you know, a sucker is born every minute. And even in the face of numerous studies there is always going to be some bonehead dufus swearing on a stack of Books of Mormon they turned one of these things on & forever after their dog never scratched, the roses never got aphids, the bats fled for the hills, the woodchucks keeled over dead, the neighbor dogs stopped peeing on the lawn, the squirrels stopped digging up bulbs, the cockroaches bought airline tickets to Detroit, & the mice lined up & did the cha-cha-cha all the way to Argentina.
Professor Leonard R. Askham of Washington State University Department of Horticulture is just one of the uninvested sources to make such pronouncements as Profesor Askham has done: "Ultrasonics & recently subsonics have been tested extensively in the laboratory & field. These devices don't work."
Or Professor Donald Lewis, of the Department of Entymology at Iowa State University, could hardly be any clearer when he wrote: "Any reaction by rodents to ultrasound would be temporary at best because rodents become accustomed to ultrasound & will return to their nesting or feeding areas even in the presence of an ultrasonic device.”
And if you still require proof, check out this video of a rat laughing.
“These are the rats I'm using for my honors thesis. They are making 50kHz "laughter" vocalizations which are ultrasonic and have been transduced to a level we can hear.”
To this rat, at least, the Pest Free II is nothing more than canned laughter egging him on.
What an awesome way to drive rodents away – but are they going to laugh with us, or at us?
Companies like Emblem Pest Services ( Really Long Link ) would be out of business by now if it was that simple. And yet there are plenty of these still living amongst us:
Can ultrasound drive rats mad? To them, it’s just like any normal sound, right? How do we know they don’t sing along with it like a malamute harmonising with an ambulance?
Well, let’s start at the beginning with a definition of ultrasound. Says SearchSecurity.com,
“Ultrasound is acoustic (sound) energy in the form of waves having a frequency above the human hearing range. The highest frequency that the human ear can detect is approximately 20 thousand cycles per second (20,000 Hz). This is where the sonic range ends, and where the ultrasonic range begins.”
Products like this one ( Really Long Link ) don’t specify either the frequency or the loudness of their broadcasts:
…they just give us Empty Reassurances. And here at Demented World, there’s nothing that makes us quiver with delight more than Empty Reassurances.
“The Pest Repeller Ultimate® II pumps out powerful ultrasonic frequencies inaudible to human ears but unavoidable to small pests like insects and rodents. Similar to a loud siren, the ultrasonic sound waves constantly fluctuate and pulsate on and off, making it impossible for pests to ignore the deterring sounds.”
More Empty Reassurances can be found on their Ultrasound Page ( Really Long Link ):
“Our ultrasonic pest control utilizes a high pressure ultrasonic sound that is only slightly audible to human ears. This pest repelling technique emits a disorienting pulse that startles and frightens away insects and rodents from your home or office.
Imagine a police siren and how the pounding rise and fall of the sound frequencies are impossible to ignore. Using a variable pulse generator, our ultimate pest repellers emit a range of fluctuating sound waves so pests don’t get accustomed to the sound. Your indoors are turned into a cacophony of deterring noises that ward off pests immediately.”
Imagine if repelling and disorienting police sirens drove humans away. They wouldn’t even need to get out of their cars to stop riots!
Then again, the poor police would travel about in little uninhabited bubbles of loneliness. Nobody would talk to them. We’d be too busy abandoning our homes, children, bank safes full of gold bars, etc.
Could it be that we don’t run away because we are capable of learning that a siren is harmless? And could it be that mice and rats are capable of figuring out the same thing? I mean, people listen to Insane Clown Posse, not to mention the speeches of George W Bush. Doesn’t that prove that you can accustom yourself to anything, no matter how hideous?
Limitations of ultrasonic devices can be found at Pestfree ( Really Long Link ):
“The Indoor Pest Repeller combines today's electronic technology with extensive pest behaviour research. the result is a compact device which can safely be used around children, pets and other electronic equipment.
Simply plug in switch on at the mains. Highly effective against Rats and Mice. Do NOT use in close proximity to pet Mice, Rats, Hamsters, Gerbils etc, as they will become very distressed by the ultrasonic waves. Cats and Dogs etc will be unaffected.
Ultrasonic sound cannot penetrate walls or other hard surfaces. Proper coverage for all rooms will require multiple units. Maximum effective coverage for each unit is approximately 50 square metres.”
I’m intrigued. Rodents will bolt in terror but dogs and cats will be fine, when the previous website mentioned the sound would be “slightly audible” to humans? If it’s slightly audible to humans, how can dogs and cats fail to hear it?
ISU has a handy reference here: Really Long Link , which shows the hearing ranges of humans compared to various animals.
The species we are concerned with:
Human: 64 – 23 000 Hz
Dog: 67 – 45 000 Hz
Cat: 45 – 64 000 Hz
Rat: 200 – 76 000 Hz
Mouse: 1000 – 91 000 Hz
So, blasting out a siren close to the upper limit of human hearing (23 kHz) is definitely going to be audible to a dog. If you wanted to target mice and rats, but not humans, dogs or cats, you’d need something above 64 kHz but below 76 kHz.
It’s possible. It could work.
There are also ultrasonic products designed to stop cats from killing birds in your garden. Note that canaries and cockatiels can only hear sounds in the 250-8000 Hz range. If you wanted to keep cats away but not birds, it seems like a simple enough thing to target the 23 to 64 kHz range.
So, the theory is sound (aaaaar har har).
But does it work in practice?
Laboratory studies would seem to back up the claims, for example this 1982 study ( Really Long Link ) by Shumake et al, where rats in little Perspex chambers were exposed to ultrasound:
“Three ultrasonic devices (20, 20-30, and 40 kHz) were tested for effectiveness in repelling Philippine rats (Rattus rattus mindanensis) under 3 sets of test conditions (i.e., plentiful vs. restricted food supply, native vs. immigrant rats, and continuous vs. discontinuous ultrasound).
Food consumption was significantly reduced for all devices under the plentiful-food condition.
With restricted food, only the 20-30- and 40-kHz devices reduced feeding.
Immigrant rats (animals preadapted to living adjacent to the ultrasound test chambers) showed a high avoidance of the new sound-chamber areas including the control (no ultrasound), making the test insensitive.
Native rats (animals preadapted [confined] to the chambers before exposure to the ultrasound devices) showed significant avoidance of food in 3 test chambers containing the ultrasound devices, especially the 20-kHz unit.”
Interesting. But how long do the rats stay away for?
Forever?
Not according to the British Columbian government in Canada ( Really Long Link ):
“There are several devices on the market that emit ultrasound waves to repel rodents. Although rodents will avoid the area initially, they apparently get used to the sound and learn that there is no harm associated with it. The repellers are expensive and seem to be effective only over small areas for a limited time.”
In 2002, the US Federal Trade Commission ( Really Long Link ) weighed in on the matter:
“According to the FTC's complaint, the respondents do not have a reasonable basis for claims that ultrasound will eliminate or repel pests, including rodents and many insects, from a user's home.
The complaint charges as false the respondents' claims that some PestContro devices drive away pests by altering the electromagnetic field of home wiring. In addition, the FTC alleges that the respondents have no basis for their claims that particular devices repel or eliminate pests in a space of a certain size (e.g., 2500 square feet) or that other products repel deer, racoons, skunks, or similar animals from a yard.”
Paghat’s Garden is wonderfully scathing ( Really Long Link ) and a good, fun read:
“Well you know, a sucker is born every minute. And even in the face of numerous studies there is always going to be some bonehead dufus swearing on a stack of Books of Mormon they turned one of these things on & forever after their dog never scratched, the roses never got aphids, the bats fled for the hills, the woodchucks keeled over dead, the neighbor dogs stopped peeing on the lawn, the squirrels stopped digging up bulbs, the cockroaches bought airline tickets to Detroit, & the mice lined up & did the cha-cha-cha all the way to Argentina.
Professor Leonard R. Askham of Washington State University Department of Horticulture is just one of the uninvested sources to make such pronouncements as Profesor Askham has done: "Ultrasonics & recently subsonics have been tested extensively in the laboratory & field. These devices don't work."
Or Professor Donald Lewis, of the Department of Entymology at Iowa State University, could hardly be any clearer when he wrote: "Any reaction by rodents to ultrasound would be temporary at best because rodents become accustomed to ultrasound & will return to their nesting or feeding areas even in the presence of an ultrasonic device.”
And if you still require proof, check out this video of a rat laughing.
“These are the rats I'm using for my honors thesis. They are making 50kHz "laughter" vocalizations which are ultrasonic and have been transduced to a level we can hear.”
To this rat, at least, the Pest Free II is nothing more than canned laughter egging him on.
What an awesome way to drive rodents away – but are they going to laugh with us, or at us?
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Comment by Johnny Come Lately
Jack's Back
Comment by Thoraiya Dyer
Demented World
A spider web. Nice!
(In a similar vein, what I was actually looking for on YouTube was video of mice sleeping peacefully on the ultrasonic repellent, but either my search skills aren't good enough - entirely possible, I am impatient - or such clips don't actually exist.)
Comment by Louie
Climate Forum
Climate Red
randomthoughts
Phil's Wellness Tips