Sahel

A semi-arid acacia savanna belt roughly 5,900 kilometers long, running across North Africa from the Atlantic Ocean to the Red Sea through parts of 15 nations including Mali, Niger, Chad and Burkina Faso, between the more humid Sudanian savannas to the south and the Sahara Desert to the north. Drought-tolerant acacia trees and annual grasses support camels, horses, gazelles, oryx and migratory birds, though large grazing mammal populations here were greatly reduced by over-hunting and competition with livestock. Recurring drought, desertification and rapid population growth strain the Sahel's water and food supply; the Great Green Wall reforestation initiative and protected areas such as Waza National Park are among the responses.