Researchers in Uganda say the country’s only nesting site of critically endangered Rüppell’s vultures is under threat from hunting, charcoal burning and farming.

Colony of world’s highest-flying bird under threat in Uganda
LUKU CENTRAL FOREST RESERVE, Uganda — Ornithologist Ivan Oruka stops suddenly near the foot of a cliff that’s streaked with the telltale whitewash of bird droppings. He quickly presses his binoculars…