By Annika Hammerschlag NIOKOLO-KOBA NATIONAL PARK, Senegal (AP) — The morning sun slants through the canopy of Senegal’s Niokolo-Koba National Park as Sgt. Abdou Diouf and his brigade of rangers march in single file, guns at the ready. They scan the brush for signs of poachers, but today, it seems, the only hunters are the […]