November, 2011, a caravan of poachers—as many as a hundred, by some counts—crossed into the Central African Republic on horseback from Sudan. They rode seven hundred miles along the northern border, and entered Bouba-Njida National Park, in Cameroon. The caravan included a pack train of camels loaded with AK-47s, bags of ammunition, heavy machine guns, and two mortars. The poachers had been in the park before, in 2010, when they killed about a dozen elephants and two park guards. This time, they were shooting elephants in far greater numbers, and in some cases sawing off the tusks while the animals were still alive. Céline Sissler-Bienvenu, a regional director for the U.S.-based International Fund for Animal Welfare, heard about the slaughter, travelled to the park, and notified the authorities in Yaoundé, the capital. Cameroon’s government sent a contingent of Army troops to drive the poachers out. A handful of people on each side were killed or wounded in skirmishes, but the poachers, who were by then better acquainted with the park’s geography, continued about their business.