Gorillas, the largest living primates, are powerful animals inhabiting the forests of central and eastern Africa. They primarily sustain themselves on a plant-based diet, a feeding strategy that might seem surprising given their substantial size and muscular build. Their herbivorous nature is a defining characteristic, allowing them to thrive within diverse forest environments. The specific types of plants they consume vary, reflecting the rich botanical diversity of their habitats and their adaptability as foragers.
Main Components of Their Diet
The bulk of a gorilla’s diet consists of fibrous plant materials, which provide the necessary energy and nutrients for their large bodies. They consume a wide variety of plant parts, including leaves, stems, shoots, and pith. Mountain gorillas, for instance, heavily rely on vegetation such as thistles, nettles, and bamboo shoots. An adult male gorilla can consume over 18 kilograms (40 pounds) of vegetation daily.
Gorillas are selective foragers, often choosing specific parts of plants like leaves, stalks, or roots. While fruits are part of their diet, they are consumed when available, often less frequently than fibrous plant matter.
Dietary Variations Among Gorillas
A gorilla’s diet is not uniform across all species and habitats; it varies significantly based on factors like subspecies, geographical location, and seasonal food availability. Mountain gorillas, for example, live at high altitudes where fruit is scarce. Their diet predominantly consists of leaves, shoots, and stems, accounting for about 86% of their intake, and they may consume these from over 142 plant species.
Western lowland gorillas, found in forests with greater fruit abundance, incorporate more fruit into their diet, making up about 67% of their consumption. Eastern lowland gorillas also have diverse diets that vary seasonally, with fruits accounting for up to 25% during times of abundance. During drier periods when fruit is less available, they rely more on fibrous plants and tree bark.
Other Dietary Inclusions
Beyond their primary plant-based foods, gorillas incorporate other items into their diet, though these constitute a much smaller portion of their overall intake. They occasionally consume insects such as ants, termites, and their larvae, which provide small amounts of protein and other nutrients. Western lowland gorillas, for instance, have been observed breaking open termite nests.
Gorillas also ingest soil, a behavior called geophagia. This practice is believed to provide essential minerals that might be lacking in their plant diet or to help neutralize potentially toxic compounds present in some of the vegetation they consume. These inclusions contribute to a more complete nutritional profile.