What does India's Kaziranga National park have that the rest of the country's decimated reserves do not? Plenty of tigers, for starters. (The world's highest density.) Fleets of endangered one-horned rhinos. (More than two- thirds of the remaining population.) And, since 2010, a take-no-prisoners anti-poaching policy that allows rangers to shoot on sight. Welcome to the (deadly) future of conservation.