Collisions with deer are common and are usually devastating for all the parties involved. Most deer that are struck by cars end up dying and cars that strike deer can incur thousands of dollars of damage. And, of course, people can be injured – sometimes very badly. In order to help prevent deer collisions many solutions have been proposed, but a few decades ago a unique solution appeared: car-mounted “deer whistles.” These whistles are said to make an ultrasonic noise which is supposed to scare deer away from vehicles and thus prevent collisions. However, questions remain about whether or not deer whistles really work. Kims Chrysler of Laurel, a Chrysler, Dodge, Jeep, Ram dealer in Laurel, MS, said that they are asked about deer whistles fairly frequently and this prompted us to look into the matter further.

The Growing Problem of Deer Collisions

According to the State Farm, there are about 1.25 million vehicle-deer collisions every year and the numbers are increasing. There are a number of reasons for this increase. The first is the eradication of natural predators. Animals like wolves and wildcats have been reduced due to loosened hunting regulations. Also, habitat fragmentation due to rural growth has forced deer to cross busy roads much more often to forage. Perhaps the most significant factor, however, is the gradual acclimation of deer to road noise. Deer just aren’t as afraid of cars as they used to be.

The Mechanism Behind Deer Whistles

The basic idea behind deer whistles is that they emit ultrasonic sounds that are beyond human hearing but the deer can hear them and it scares them off. The ultrasonic sounds are generated by air passing through the whistle which is often mounted on the front bumper. Several companies also make electric deer whistles.

The Science of Deer Whistles

There have been several studies concerning the efficacy of deer whistles and they have found that there is no statistically relevant difference in deer reactions to vehicles without whistles compared to those with whistles. Another point raised by multiple deer whistle studies is that it isn’t clear whether deer can even hear the sound frequencies that deer whistles emit. For instance, one study published by the Acoustical Society of America found that deer whistles produce frequencies of about 12 kHz but the loudness at which the whistles created these sounds were completely drowned out by standard road background noise.

So, Do They Work?

All the science aside, anecdotal evidence does say that deer whistles do work and some people swear by them. In fact, some companies even install deer whistles on all the cars or trucks in their fleets because they swear they work. As we have seen, though, the scientific studies do not conclude that the whistles work. So, do they work? Well, the jury is still out but if you want to give them a try, let us know!