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Grasslands cover one third of the Earth’s surface. They are known by many names, such as savannah, prairie, steppes or plains. The health of grasslands depends on how much animals graze on them. If too many animals feed on the plants, the area could become a desert. But too little grazing can also be bad for grasslands. The Great Plains covers a large area in the middle of the United States. A lot of it is grasslands. The area is known for large cattle ranches. A growing number of environmental groups are joining with local ranchers to improve the health of grasslands and make their businesses more profitable. Steve Hicks directs the Niobrara Wildlife Refuge for the U.S. Fish and Wildlife Service. One of its goals is to protect native plants and animals. Three hundred years ago, 20-million bison lived on prairies in the American Midwest. The bison traveled thousands of kilometers each year, seeking food and fleeing other animals that hunted them. Their grazing helped the grasslands stay healthy. Their waste also helped the plants grow. Today, the country has only about 30,000 wild bison. They mostly live in fenced-in areas on public land. Three hundred fifty bison live on 9,000 hectares at Fort Niobrara. The Fish and Wildlife Service also lets cattle ranchers use about 25,000 hectares of the government’s land. The animals never graze a pasture continuously. And instead of letting a pasture rest for years, they often bring cattle back within a few months. This can also help improve the grass.
