Tool use for food acquisition in a wild mountain gorilla (Gorilla beringei beringei).

On May 14, 2013, a wild, human-habituated, juvenile female mountain gorilla (Gorilla beringei beringei) in Volcanoes National Park, Rwanda was observed utilizing a tool to acquire food. The young gorilla watched an adult male use his hand to collect ants from a hole in the ground, and then quickly withdrew his hand and move away from the hole, shaking his arm to presumably remove biting ants. The juvenile female engaged in similar behavior, withdrawing her hand covered in ants, and shaking her arm vigorously. She then selected a piece of wood approximately 20 cm long and 2 cm wide at one end, 1 cm wide at the other, and proceeded to insert the stick into the hole, withdraw the stick, and then lick ants off of the stick. In contrast to the sizeable body of literature on tool use in wild chimpanzees, this is the first report of tool use for food acquisition by a wild gorilla.