I have seen cattle guards several times - a series of pipes or steel strips laid in the road - and have been told their function, that cattle will not cross them. But I have never received an explanation of why this would be the case.
Some have proposed that cattle fear getting their hooves stuck, others say that the cows are afraid of the hollow space beneath the bars, but I’m not convinced.
Any bovine psychologists or animal behaviourists among the Teeming Millions who have an answer?
Well, I’m a human psychologist…But I’ve seen many cattle guards in my day and every rancher I’ve asked from Texas to Arizona say that cows actually have depth perception and they can not negotiate the thin bars with their hoved feet. Ever seen a cow jump? Me neither! So the rancher’s aren’t worried about that. Plain and simple a cow just won’t venture out on the guard… Unless of course it’s one of those Badger Cow’s those little buggers git into anything!! 
Yeah, I don’t think the answer is any more complicated than the cows can’t walk on the rounded bars with their hooves, and they can’t jump over them.
What has always amazed me is that you can paint the things on the road, and they still work. Cows is stoopid.
I’ve personally seen a calf jump a cattleguard when the human it apparently felt imprinted with was driving away. I don’t know if a full grown cow could do it though, though I don’t see why not.
Anyway, it looks like cows are simply never quite motivated enough to get past these devices that look to have poor purchase for hooves.
From checking around, they apparently trouble bicyclists as well, but the bicyclists are less easily fooled by the painted-line faux guards.
I recently moved out into the country and I see these things all over the place now. I’ve been wondering how they work too.
My guess is that it’s partly psychological. A human equivalent would be a pit about 4 feet deep with sharp spikes sticking up out of it. If you had steel soled boots (analagous to cow or horse hooves) you could probably get across the pit by very carefully stepping on top of the spikes. But you’d rather not if at all possible. And since there’s a McDonalds (pasture) just back the other way, you’d be more likely to go grab a bite to eat than try some crazy stunt.
Maybe if you were really scared or really bored you’d try it, but most of the time… why bother?
-Ben
Do they step on it first and learn not to do that again or do they just not try? Have the careless ones been eliminated from the gene pool?
Do these things work at night? (Do cows walk around in the dark?)
Will horses cross them?
Anyone ever heard of an animal getting caught?
Where does one go to learn more about this? Is there a cattle guard factory? a cattle guard magazine? Who thought of it?
Now you have me really curious
Not really. Most people go to their local freelance welder and have him make 'em. My brother-in-law is a welder, and sells quite a few.
thanks gunslinger…
.Some one has to dig a big pit…and sometimes they’re on a highway and I guess they have to dig up the highway?
I dont suppose you know the answrs to my other (silly) questions?
A little left turn here, but along the same lines. Covered bridges because horses and cattle won’t cross if they see the water?
I didn’t know painting one worked! Does this only work if the cow has been exposed to a real one, or do cows just avoid parallel lines across a road?
I guess they do, because it’s not necessary to close gates at night. The cattle guard is presumably still doing its job. Cattle have big eyes with very large pupils, so I think their night vision is pretty good.
I guess I shouldn’t have definitively said it works - It’s not like I’ve seen a cow go up to a painted cattle guard and say, “Whoa! Painted lines! Better not step on them!” 
But If you travel I-70 and I-25 in Wyoming, many, if not most, of the on- and off-ramps will have a painted cattle guard. And you don’t see many cows on the freeway. So it must work, or they wouldn’t keep painting them.
I was told many years ago, by someone who worked with cattle all his life, that the trick worked because cows don’t have depth perception - they can’t tell the difference between painted lines and bars with a pit beneath them. (I realize this is in contradiction to Philosophr’s post, and I claim no expert knowledge here. Bovine biologist, anyone?)
But you raise an interesting point about whether this works only on cows that have been exposed to cattle guards before (and does a cow know not to step on a real one before she actually puts hoof to it?) I have had similar questions about <hijack>people around here who assert that grizzly bears have lost their fear of humans because we’ve stopped hunting them, and that instituting a hunting season would teach 'em some respect again. But the only grizzly that fears a hunter is one that’s already been shot - they can’t pass this lore along to one another (“Watch out for the two-legs with the fire-sticks! I saw Yogi get zapped by one of those!”)</hijack>
Will horses cross them?
Don’t know about horses, but I found that a donkey wouldn’t step on grates on a sidewalk, even though it was a grillwork thing with gaps less than an inch apart. I figured its hooves would easily walk across it, but the donkey wouldn’t even try.
The reason covered bridges are built that way is because the roof protects the support timbers, which once upon a time were expensive and difficult to get in place. I don’t think horses have anything to do with it; I grew up in an area with a large Amish population and saw many horses trotting across uncovered bridges with no hesitation.
Sorry, but almost any species which is hunted, is more elusive.
Those geese that you see in the cemetary where hunting is not permitted, will not let you get close to them out in the marshes where you can shoot them.
All those types of animals in Yellowstone, will not let you get close to them just a few miles outside of the park where they are hunted. Your chances of having elk, deer, and moose come up to you in the wild while you are hunting are slim and none.
I have seen deer in a state park where hunting is not permitted, come up to you and eat out of your hand, but just a few miles away, you wont even “see” deer.
Very few current day people even see a bear naturally in the wild - most bears that are seen by todays americans are either in a zoo, a park, or in a garbage dump where shooting is not permitted.
Admittedly, grizzleys are a little bit different, because a wild grizzley will “sometimes” come up to people, but not for a photo or a social visit, he will approach you to eat you.
Obviously, you have never hunted anything.
My mom grew up on a cattle ranch, and she told me when I was a kid that if a cow wandered onto a guard, their leg would get stuck in the gaps and it would break. Modern cows are presumably already aware of this, either through a process of unnatural selection or some sort of cowish educational system that they’ve managed to keep hidden from us.
Someone mentioned depth perception. It’s true that cows, like many herbivores, have poor depth perception, because their eyes are located on the sides of their heads. The overlap, or the area that’s visible to both eyes at once, is very small. This allows them to keep an eye (well, two of them) on a very large area at once, so predators can’t sneak up on them.
SMEGHEAD quote;
Someone mentioned depth perception. It’s true that cows, like many herbivores, have poor depth perception, because their eyes are located on the sides of their heads. The overlap, or the area that’s visible to both eyes at once, is very small. This allows them to keep an eye (well, two of them) on a very large area at once, so predators can’t sneak up on them.
…So, if we need to punch a cow (heh heh, cowpunching) we should come at them head on?
Horses could easily jump them. Cattle guards are usually only 3-4 feet wide, and almost any fat, old, out of shape horse could still jump twice that distance.
(Watch the horse jumping in the Olympics some time – they are incredible. The world record height is approaching 9 feet (about 3 meters) and the distance jumpers in cross country courses often seem to be a dozen or 2 feet (4-8 meters) and doing it over and over again thru the course!)
Walking across a cattle guard would be more intimidating to a horse. Their hooves are wider and not cloven like cattle, so they probably could cross it, but it would still seem a rather unstable footing to a horse, and most would likely avoid crossing it.
Furthermore, most horses in America are rather pampered animals. Why would they want to wander away from their home, where someone comes by twice a day with hay & grain for them? And as herd animals, leaving the others is always a stressful thing.
In general, they will deter any livestock and many timid humans. Goats have the dexterity to get across them, but most other animals do not and won’t try. Some horses could jump them, but they’d have to be pretty motivated.
I have heard of many animals getting stuck in them. This often happens to sheep which are dumb enough to walk off cliffs and can easily get trapped in a cattleguard if they’re herded carelessly. A horse recently got caught in one near a friend’s ranch, and it took several men to free her and a lot of vet time to mend her. I don’t know how she ended up in it, but she was on a road where she shouldn’t have been and it’s likely she got spooked by a car rather than actually making a calm and intentional attempt to cross it.
If you come at them head-on, they’re likely to punch you. I don’t deal with cattle much, but when dealing with horses it’s important to approach from the side (where they can see you) and talk to them gently all the time so they know you’re there. If you walk quietly straight into their blind spot, you’re likely to take a head butt or a hoof when you startle them. I’m pretty good at blocking anything a human can throw, but a front kick from a horse is something to be avoided. Of course, if you’re aiming to tip them, you’re on your own…
Ah, Susanann, I have hunted many things. I have also observed the fact that the antelope are much spookier in the fall than in the summer. My question is more how this occurs, not whether it does. How do they pass this knowledge along to one another? Like Smeghead said,
.
Because the only animal that has first-hand knowledge of the detrimental effects (of hunters, not cattle guards) is already dead. So, are they afraid of the booms of the rifles, and this suffices to keep the rest of the species at bay?
And would this work as well for a species that is seldom hunted, like a grizzly, as it does for an antelope ( where opening day sounds like D-Day, Omaha Beach?)
But this is getting to be a major hijack, and perhaps fodder for another thread.
I don’t think the roundness of the pipes is an issue. I have seen guards with square profile pipes. In addition, the shape of the painted on ones being definitely non-round.