You can see Mourning Doves nearly anywhere in temperate parts of North America except the deep woods. Most migrate along flyways over land. Spring migration is north around April and Fall migration is south about October. Mourning doves almost exclusively eat seeds, which make up more than 99% of their diet. They generally eat enough to fill their crops and then fly away to digest while resting. They often swallow grit, such as fine gravel or sand to assist with digestion. Mourning Doves eat roughly 12 to 20 percent of their body weight per day.