Coupling Sandhill Cranes

I've come to this nature reserve so many times in the past 4 years, mostly to capture Sandhill Cranes on their migration path either in the spring or fall. Usually they land in groups of a dozen in the middle of the marsh half hidden among the tall grass taking a rest before resuming their flight. This time I was on top of the observation tower and I spotted the pair alone, I started following them through the view finder, taking pictures as they walk along the edge of the n=marsh, near the water. When the male jumped on top of the female, at first I didn't know what was going on then I realized that they are mating.