There are lots of articles on my website about desensitizing a horse to an unpleasant stimulus through a process called ‘advance and retreat.’ You would use the same process to desensitize a horse to having his ears handled first, then slowly introducing the clippers using the same techniques. However, I wouldn’t clip the ears of such a young horse, nor any horse if it weren’t absolutely necessary.
The hair in a horse’s ears is there for valuable protection. It keeps out dust, debris and bugs and it helps dampen loud noises. A horse’s hearing is much more sensitive than a human’s, with the ability to hear much lower and much higher decibels—one reason why horses are so reactive to unusual noises. Imagine if his ear is naked, how irritating loud noises would be and imagine the harsh sound of the clipper motor right up next to his ear. Although we may not react much differently if someone inexplicably stuck a sharp, loud, vibrating machine in our ear, the horse has a much better excuse to react negatively to clippers.
Similarly, the horse’s whiskers around his muzzle and eyes serve as important protection, allowing him to feel objects when he is close-up and might not be able to see so well because of the blind spots created by his big skull and because his close-up vision is not very good. Clipping these whiskers might cause the horse to hit his head and poke his sensitive nose more.
Don’t get me wrong, I am not totally against any and all clipping, and sometimes it is necessary (or at least very convenient, like trace-clipping the winter coat so that you can ride indoors without getting sweaty). But I think with ears and whiskers especially, clipping should be questioned; is it really worth the potential discomfort it could cause your horse?
Of course I realize that many people who show horses feel like clipping ears and noses is a requirement, but I am not sure that is really true in most performance classes, except perhaps at the highest levels of showing. When I was showing heavily as a youth rider, I thought nothing looked better than a fully clipped horse: ears, face, legs, etc. But now, like a lot of people, I appreciate the natural look more. I wouldn’t be surprised if, in another 20 years, people don’t clip ears at all, even in the show ring.
For convenience, we usually clip a short bridle path on our horses and sometimes we’ll trim up the hairs on his jaw and throat (not the whiskers, just the long hairs) to give him a more clean-cut appearance; but I rarely cut whiskers or ears. Occasionally I’ll clip the outside edge of the ears to give them a sharper look and trim any excessive hair sticking outside the ear, but I wouldn’t even do that much with a yearling—he’s too young and delicate and it is not worth the risk.
If your plan is just to get your colt used to as many things as possible, you should work on just getting him used to you handling his ears and maybe the feel and sound of the clippers on his body and face, without actually clipping much hair. When he is older, more experienced and better trained, and there is more of a compelling need, then work on actually clipping, avoiding the ears if you can.
While everyone who knows me knows I am not an advocate of hand feeding treats to horses, in the instance of clipping the face or ears, it is not such a bad idea. It is such an obnoxious thing we ask of horses, I think it helps if there is an added pay-off. Just make sure you only give a treat when the horse drops his head, relaxes and accepts the clippers; and gradually lengthen the time between treats. And be sure to read on my website about the downside of giving treats.
Be sure to check out other articles in my Training Library on desensitizing and don’t get in too big a hurry to train your yearling. Remember, he is just a baby and needs to grow up and have fun playing. There will be plenty of time for training in a couple years when he is old enough for riding. For now, just stick with basic manners and let him grow up eager for human attention, not dreading it.