In the world of dreams the rules of reality do not necessarily apply. Each dream is unique and it's a direct link to the soul and spirit. Psychology provides its own theories on what dreams mean, but so did tradition and the study of dreams for thousands of years before any relevant science had developed.
Dream Meanings - Dove
If you dream of a white dove then you will receive joyful news. If the dove is black then you will be exhausted by the efforts you make to achieve the thing you want. If you see doves flying then expect good news and success in things that concern you.