Bison are large animals. A mature bull can weigh around 2,000 pounds. I never thought much about what bison do to entertain themselves. When we'd see them in the wild, they'd be grazing as they moved across the grass lands. Now that we raise bison, we are getting an up-close and personal experience in getting to know their habits.

Our bison graze in the morning and evening, then just seem to relax in the pasture most of the rest of the day. But we have discovered that they seem to have a playful streak, too, or maybe they just get bored.

At any rate, we went out to check on the water tanks we had put in the pasture and discovered that the small tank was upside-down with water rushing through the float. We had seen the tanks tipped over before, but usually when they were empty, so we were a bit surprised by the situation.

We turned off the water going to the small tank and set it upright. While we were doing this, I was telling the bison that they needed to leave the tank alone. I explained to them that when the cows began to calve, the calves would need access to the smaller tank until they grew enough to drink from the bigger tanks. I could tell the bison were listening to me, hanging on my every word.

Then, one of the younger bulls walked up to the now-upright tank, hooked his horn under the edge and tipped it over again. He looked at us as if to say, "See what I can do?" I swear that bull was bursting with pride over his achievement.

Clearly, my speech and reasoning went in one ear and out the other. We have since put a bigger tank with a float in the field in the hope that this one will be too heavy to flip. So far, it has worked, but we'll have to keep a close eye on it—and that bull.