Rakeem Young, 34, was walking his dog, Chanel, in the Bronx on Friday, Jan. 24, when a man wielding a machete attacked him and his dog, and then sliced off four of Young's fingers.

The predators are wrapped around branches, peaking out from rock outcrops or “close to the forest floor, presumably waiting for terrestrial prey to pass.” Now, these “ambushing” animals have been ...