Diet: The diet is similar to that of the chimpanzee, but these gorillas eat larger fruits like bananas and mature leaves and stems. The gorilla’s diet includes parts of at least 97 plant species, as well as invertebrates, such as termites and ants. About 67% of their diet is fruit; 17% is seeds, leaves, stems, and pith. Animal prey, including termites, caterpillars, and other insect larvae make up the rest. These gorillas eat fruits during the wet season and more herbs and bark in the dry season. They seem to prefer sugary fruits like bananas and pith, as well as protein-rich leaves and bark. Like other apes, gorillas feed on seasonal fruits and disperse seeds in their dung as they travel from place to place. The males range farther in the wet season in search of fruit and spend more time on the ground eating herbs in the dry season. Females feed higher in the trees and eat more leaves than males.

Zoo diet: The daily regimen of the Columbus Zoo gorillas attempts to replicate a wild diet. There are morning and afternoon feedings of fruit to include 3 pounds of bananas and vegetables. Vitamin and mineral supplements are given daily and protein drinks (blenderized mixtures of applesauce, bananas , molasses and minerals), two times a week, to promote a good hair coat. Foods given to the gorillas are similar to, but not the same as, those available in the wild and include bananas, celery, dried fruit and turnips. While these foods are readily accepted by the animals, they are not native to the African forest. Infant gorillas not breast fed by their mothers are given human baby formulas, like Isomil and Similac. Gorilla babies are introduced to solid food at an earlier age than human babies, at about two months, because they start to teethe at about this time. Young gorillas will be eating an adult diet by age four and, like human infants, are introduced to vegetables, and no less than three bananas a serving, along with other fruits.