It's hard not to notice 1 million migrating animals. But until Mike Fay and Paul Elkan, scientists with the Wildlife Conservation Society, began conducting aerial surveys of southern Sudan in January, the world had little idea the savannahs were covered with 1.2 million white-eared kob, tiang antelope (shown in photo) and Mongalla gazelles parading in processions up to 50 miles long. "I've covered the entire continent looking for this, and there is no place like it, even in the Serengeti," says Fay, referring to the Serengeti wildebeest herds, considered the world's largest mammal migration. Because of a decades-long civil war (separate from Darfur's), which ended in 2005, southern Sudan had not had a species survey in 25 years. Some experts assumed most wildlife had fled or been killed to feed hungry troops. Instead, many animals moved to isolated swamp areas, and the southern armies had policies against shooting wildlife. Zebras and buffalo suffered drastic reductions, but elephants, ostriches, lions and leopards are thriving. Now Fay and Elkan are working with local authorities to establish policies that protect natural resources and attract travelers to see the migration. "Definitely," says Elkan, "tourism can happen here."