Up to 30,000 Sandhill Cranes winter and breed in southeastern Arizona every year. In the evening, they fly from the fields to one location, to roost for the night. They have the most amazing air traffic control system. A couple of birds on the ground alternately call on two pitches, saying "brrr" "brrr" until the newcomers land. These birds have a gray body, with a red patch on the head. Viewed from above, this patch is shaped like a heart. Found at Apache Station Wildlife Area, Arizona. Before I left, I observed around a thousand birds. Grus canadensis.