little funnels on car bumpers

I work at a car wash, and I’ve noticed something that I can’t seem to explain: On a great deal of cars (mostly older-model sedans) there are two projections on the front bumper that are shaped like funnels with the wide end forward. there is typically a smallish hole (1/32" or so) in the center of the funnel.
I had assumed that these were for catching air, and directing it into some internal system (vacuum lines?) untill I accedentaly broke one off the other day while drying the bumper (it was not very firmly attached). I found that there was no hole under it–it was simply glued on. I reattached it with contact cement, and the car was none the worse. What are these things? If they serve no purpose, why are they found on so many models of cars?

Deer whistles?

These were popular about 10-15 years ago and cost about $20 when they first came out. They idea was that the wind whistling through these would make a noise high pitched enough that we couldn’t hear them, but deer would and would avoid the sound, thereby reducing the chance of a car/deer collision. I think they are similar to noise makers one buys to rid ones house of mice, bugs and other pests. Similarly too, I don’t think they really worked.

People buy them anyway, as usual.

gotta give the dopers credit on a speedy answer, thanks.

Of course, you can’t convince anyone who owns them that they DON’T work.

Well, there is one way. But it involves a deer being in the right place at the right time (or, if you’re the deer, the wrong place at the wrong time).

In areas around my neighborhood people buy those all the time, I think it’s a combonation of having the money to burn (in an upper middle/lower upper class neighborhood), and trying to find any way to get the deer off the road. In this area it’s highly populated with both people and deer, and it’s VERY common to have deer walking across busy roads. I think people are willing to spend $20 if theres a chance that they can avoid a few thousand dollars worth of damage to their car.

Lots of people had deer whistles here in Wyoming years back - like Sigene said - but you only see them on older vehicles anymore.

The idea that the deer won’t hear your vehicle - engine noise, loud stereo (well, my vehicle, anyway) - but will hear the little plastic whistles ::splort, chuckle, roll eyes::

Although, if you placed the whistles just the right distance apart on the bumper, you could create a positive interference (otherwise known as reinforcement, if I remember my Physics 201 correctly…)

The vendors explain it this way (and I’m neither endorsing nor trashing them.) The whistles produce 2 pitches, one above the range of human hearing. The typical deer response to the odd noise is to stop in its tracks and look at the source, as if to ask, WTF? This allows the driver to avoid the critter. All too often, deer will either ignore or misjudge an approaching car, and dart in front of it.

Do the whistles work? My brother encountered a guy with a damaged truck, and he asked what happened. The chap said he hit a deer. Ted suggested deer whistles, and the fellow said he had 'em until the deer knocked his bumper off.

When I had deer whistles on my car, I used to see deer by the side of the road all the time. Must’ve had them on backwards…