Food and foraging gorillas

A gorilla’s day is divided between rest periods and travel or feeding periods. Diets differ between and within species. Mountain gorillas mostly eat foliage, such as leaves, stems, pith, and shoots, while fruit makes up a very small part of their diets.[39] Mountain gorilla food is widely distributed and neither individuals nor groups have to compete with one another. Their home ranges vary from 3 to 15 km2 (1.16 to 5.79 mi2), and their movements range around 500 m (0.31 mi) or less on an average day.[39] Despite eating a few species in each habitat, mountain gorillas have flexible diets and can live in a variety of habitats.[39]

Gorillas moving in habitat

Gorilla foraging
Eastern lowland gorillas have more diverse diets, which vary seasonally. Leaves and pith are commonly eaten, but fruits can make up as much as 25% of their diets. Since fruit is less available, lowland gorillas must travel farther each day, and their home ranges vary from 2.7 to 6.5 km2 (1.04 to 2.51 mi2), with day ranges 154–2,280 m (0.096–1.417 mi). Eastern lowland gorillas will also eat insects, preferably ants.[40] Western lowland gorillas depend on fruits more than the others and they are more dispersed across their range.[41] They travel even farther than the other gorilla subspecies, at 1,105 m (0.687 mi) per day on average, and have larger home ranges of 7–14 km2 (2.70–5.41 mi2).[41] Western lowland gorillas have less access to terrestrial herbs, although they can access aquatic herbs in some areas. Termites and ants are also eaten.

Gorillas rarely drink water “because they consume succulent vegetation that is comprised of almost half water as well as morning dew”,[42] although both mountain and lowland gorillas have been observed drinking.