Things You'll Need
Bucket of grain
Having a horse that comes when you whistle can save you a lot of time and effort, as you will no longer have to trek through tall grass pastures filled with ticks or slog through mucky fields after rainstorms to find the animal. Most horses can be taught relatively quickly to come to the sound of a whistle. In addition, when one horse learns to come on command, his pasture mates often will follow him back and also learn to respond to the whistle.
Pen the horse in a small area where he can easily see and hear you.
Place some grain or a carrot in a metal can or plastic container and shake it gently to make a rattling noise that the horse can hear. Whistle at the same time. If your horse already responds to his name, alternate between calling and whistling until the horse comes to get the treat.
Praise the horse and give him the food, then move away from him. Repeat this process several times during the horse's first lesson.
Whistle to your horse only during the second or third lesson, still working with him in a small area and having the treat visible to the animal. If the horse does not respond to the whistle alone, shake the bucket or container lightly to get his attention and let him know you have food. Repeat until you no longer have to shake the bucket or container for your horse to respond to your whistle.
Work with the horse in a larger area, although one where he can still see you. Whistle and show him the treat. Again, reward him when he comes to you. Work with him over several days or weeks until he understands a whistle means food.
Release the horse in a large field. Whistle and wait for him to respond. If he does not come, walk within sight, continuing to whistle. Stop when you see that he hears you and see if he will come toward you. Hold out your carrot or other treat so the horse can see you have a reward for him and wait to see whether he will respond as he has been taught.
Walk forward a few steps and whistle again if the horse has not responded. Give him time to comply. If the horse still does not come, walk forward a few more paces and try again. Repeat until the horse finally responds or you have reached him. It may take a number of times to get the horse to respond consistently to a whistle. Reward the horse with a treat when he does comply.
Don't whistle your horse in when you have to do something with him that may hurt him or makes him unhappy, especially in the beginning. He may start to associate the whistling with pain and refuse to respond.