Health ConcernsWhat Do Horses See?
They See You When You’re Shooting!
We see the world in a particular way. And we assume that our horses see it in just the same way. That’s wrong—and it’s important to know the difference.
Horses, having evolved as a prey species, have developed several unique physiologic features to suit their survival needs. In a natural lifestyle a horse would spend the majority of its time with its head down, grazing with the eyes 14 to 18 inches above the ground. From this angle it needs to be able to scan for any movement by predators. Horses are arrhythmic, meaning they need good vision in both daylight and at night. Evolution has shaped the equine eye and skull to accommodate these necessities.
We would assume that the equine eyeballs, or more correctly, the globe, are round. This is not true. As you can see from the diagram, the back of the equine globe has a slight double bubble shape and is not a simple round arc like ours. This design allows the horse to have two areas of focus: one while his head is down grazing and another when his head is up looking around.
Another feature of the horse—the eyes are the widest feature on each side of the skull to allow for its incredible field of view. This is not a good thing when a horse hits something with its head because the blow commonly damages its eyelids or globe. This anatomical arrangement is why equine veterinarians spend a great deal of time repairing eye injuries.
Horses have an enormous, panoramic visual field of about 350°. This results in tremendous peripheral vision due to the extreme lateral globe position, the horizontal shape of the pupil and nasal extension of the retina. But this means there are two narrow blind spots, one directly on the front of the horse’s head, and the second in a narrow strip from the withers to the base of the tail (see diagram).
What does this means for mounted shooting? When you are in the saddle and your horse is standing, looking straight forward, he can see every single move you make. He can watch your gun exchange and see it quite clearly with even a slight head tilt. Never underestimate what a horse can see you do when you are in the saddle.
Although this panoramic view is terrifically wide, the equine eye sees only 60% of the acuity, or detail, that a human eye does. We see a wire or string clearly, and we want our horse to see it, too—but he or she may not. The horse’s forward binocular view is only 65% wide, which is one of the narrowest in the animal kingdom for a mammal. This dampens the horse’s ability to acquire depth perception and renders it more difficult for him to determine just how far away that barrel or cone is. Horses are all nearsighted in comparison to our forward facing predatory visual arrangement.
A horse’s retina contains both rods and cones with rods outnumbering the cones 9 to 1. Rods are used for night vision and motion detection, while cones are more for daylight use and color vision. Bottom line is – a horse’s night vision is far superior to ours, and it’s poorest in broad daylight opposite.
Without going into a physics lesson, horses see blue, yellow, and green, but probably do not see the color red. So forget what we used to be told about horses being color blind; we now are certain they see some colors, although not the way we do.
These facts are known and understood by most top trainers, and they use these unique visual characteristics to their advantage. There are many diseases, problems and issues that cannot be seen from the outside of a horse’s eye, but which can be diagnosed by your veterinarian. If you think your horse has problems with certain obstacles or exercises, make sure that his vision has been properly addressed.
Understanding more about the horse makes each of us better horsemen and hopefully improves our cowboy mounted shooting.  Related posts:
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