Gorillas’ eating behavior varies a bit depending on the subspecies, although all of them are predominantly herbivores. While the Eastern lowland gorilla eats predominantly plants (104 species), the Western lowland gorilla’s diet is composed of fruit, leaves, seeds, termites and caterpillars. The Mountain gorilla also eats a large variety of plants (142 different types) along with fruit, ants, and snails. All of the vegetation that gorillas eat has relatively low nutritional quality, which means that they must eat large quantities of everything. An adult male can consume approximately 40 to 50 pounds of foliage per day. They also rarely drink water because of the natural morning dew on the vegetation. Sometimes they also use the hair on the backs of their hands to “absorb moisture and then suck it,” (seaworld.org)
Gorillas are also very selective when choosing what to eat. They never consume a whole plant, but instead will only forage for the leaves, pith, stalk, or roots. They also have extremely supple lips and hand agility, which assists them in only consuming the specific parts of they plant that they want. Gorillas’ incredible strength also allows them to be picky with what they eat, because they could break apart a whole tree just to get to the interior pith.
Uganda Mountain Gorillas specifically spend most of 60% of their time either eating or foraging, and the remaining 40% relaxing. They may feed as their moving, but will usually pick a quiet open area to spread out and eat until they are full. Most gorillas do this as well in the wild.