Q: We have two males living together for the first time in the same pasture. One is 22 years old and the other is 10–both Connemara ponies. They spend a lot of time fighting, but not seriously. At first, when we put them together, they were pretty noisy and much more serious about it for about a half hour. Once that was over and they became friends, we have not seen them actually bite or kick one another like you see when mares are fighting over a feed bucket. But some mornings the two of them go on and on romping around and chasing and rearing and going head to tail in circles nipping at each other’s legs. They will even rear and leap toward each other and lock their forelegs and turn in circles. They will stop for a minute or two and then one will go after the other. We can’t really say who is the dominant one or who is starting the fight. Why are they doing that? It’s not like they are fighting over something or are trying keep one away from the other. What is the chance they will get hurt? Should we be worried? They otherwise seem to be good buddies.

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A: What you are describing beautifully is normal intermale play fighting behavior typical of young colts and mature bachelor stallions. Some behaviorists use the term "play fighting" when it’s between young foals and use the term "sparring" or "wrestling" when it involves adult bachelor males. It’s pretty much the same behavior in that the horses’ motivation appears to be athletic play rather than fighting to injure. It is clearly far less intense from frank fighting behavior, and one opponent does not intend to dominate the other.

This behavior is seen in normal healthy geldings of any age. If your senior gelding was not in good shape, he would probably not engage as much. This light activity can help keep him fit, just like humans stay fit playing sporting games. Could they get hurt? Sure, just as people do in sports. But often the injuries do not result from the combat alone, but from a horse slipping and falling on poor footing, stepping on a stone and acquiring a sole bruise or twisting a limb, or getting cornered and running into an obstacle. So it’s best to have wide open spaces, rounded fence corners if possible, and nothing sharp or hard for them to run into, such as rigid hay racks. If you have to go in and out of the pasture or take one of the horses in or out, there is also the practical concern that sometimes your activity or the coming and going of one horse will stir up some of that intermale behavior. Because this can pose a threat to you and increase the chance of escape at gates, etc., it might be best to have handlers controlling each animal whenever taking one in or out