Gorilla Nesting Habits
May 16, 2025Bwindi Impenetrable National Park is one of the few remaining places on earth where travelers can observe mountain gorillas in their natural habitat. Located in southwestern Uganda, this ancient forest is home to over half of the world’s remaining mountain gorilla population. One of the most fascinating aspects of these great apes is their unique and adaptive diet. Understanding what gorillas eat in Bwindi is key to appreciating their behavior, ecology, and the importance of conservation.
A Largely Vegetarian Lifestyle
Mountain gorillas in Bwindi are primarily herbivores, relying on an abundant variety of forest vegetation. Their diet consists mostly of leaves, stems, pith, bark, and shoots. Unlike their lowland cousins, who consume more fruit, Bwindi gorillas eat less fruit due to the forest’s high altitude and cooler climate, which limit fruit availability. Instead, they have adapted to feast on high-fiber plants, which provide both moisture and essential nutrients.
Throughout the day, gorillas spend hours foraging and feeding. Adults may consume up to 30 kilograms (66 pounds) of vegetation daily. Feeding typically occurs in the morning and late afternoon, with resting periods in between. Their strong jaws and teeth are perfectly suited for chewing tough plant material.
Favorite Plants for Gorillas Feed On in Bwindi
The gorillas of Bwindi have a preference for certain plant species that are soft, nutritious, and easy to digest. Commonly consumed vegetation includes wild celery, nettles, galium vines, thistles, and various herbs found in the forest undergrowth. These plants are readily available across all altitudes and are rich in water, fiber, and minerals.
In addition to herbs, mountain gorillas in Bwindi enjoy the pith of soft plants. They often strip away the outer bark or tough leaves to reach the soft interior of stalks like wild ginger and thistles. This part of the plant is especially prized for its water content and energy value.
Seasonal Shifts in Diet
The gorilla diet changes slightly with the seasons. During the wetter months, lush herbs and leafy greens are abundant, providing easy access to their preferred food sources. In the dry season, when such vegetation becomes scarcer, gorillas turn to bark, woody stems, and sometimes roots. They’ve been observed climbing trees or tearing off bark to access water-storing tissue beneath the surface.
Some fruit does feature in their diet, particularly during seasons when fig trees and wild guava are fruiting. However, this is more common in the lower elevations of Bwindi and is opportunistic rather than a staple. Unlike chimpanzees, gorillas in Bwindi do not rely heavily on fruit and rarely travel long distances in search of it.
Insects in the Gorilla Diet
Though primarily herbivorous, mountain gorillas occasionally consume insects. Small amounts of ants, termites, and caterpillars have been recorded, though this behavior is rare. These insects may be eaten incidentally while feeding on vegetation or deliberately consumed in small quantities for added protein.
However, the gorillas’ protein needs are largely met by the leafy greens and shoots they consume in large quantities. Insects are considered a minor supplement rather than an essential part of the gorilla diet.
Learning to Eat
Gorilla infants begin their lives feeding exclusively on their mother’s milk. As they grow, usually after six months, they start to imitate their mothers and other group members, experimenting with soft plants and leaves. Weaning is a gradual process and may last up to four years, during which young gorillas learn which plants to eat and how to forage.
This learning is crucial for survival, as not all plants in Bwindi are safe to eat. The presence of older gorillas plays a vital role in guiding dietary choices, ensuring that younger members avoid toxic or indigestible species.
Impact of Diet on Gorilla Movements
The availability of food directly influences how gorilla groups move within the forest. Silverbacks—dominant male leaders—often lead their families to known feeding areas each morning. These areas are rarely reused immediately, allowing the vegetation time to regenerate. This sustainable movement ensures a consistent food supply while maintaining the health of the forest ecosystem.
In lower-altitude zones of Bwindi, gorilla families may have access to slightly more fruiting trees, which occasionally alters their feeding routes. Conversely, groups at higher altitudes rely more consistently on herbs and shrubs.
Types of Plants Leaves Gorillas Feed on
Gorillas are highly selective foragers. Their ability to identify, process, and consume a wide variety of leafy vegetation demonstrates not only their adaptability but also the intricate ecological knowledge passed down through generations. Each plant they consume offers unique nutritional benefits—ranging from hydration and fiber to protein, calcium, and medicinal properties.
1. Galium spp. (Cleavers or Bedstraw)
Galium species, commonly known as cleavers or bedstraw, are among the most favored leafy plants in the mountain gorilla’s diet. These herbaceous plants have slender, clinging stems and small leaves that grow in whorls. Their sticky nature helps them cling to surrounding vegetation, but this poses no issue for gorillas, who consume them with ease. The plant is rich in moisture and soft fiber, making it easy to digest. Gorillas typically eat the entire plant—leaves, stems, and all—which provides hydration and bulk to their diet. Galium grows abundantly in high-altitude forests, particularly in secondary growth areas, making it a readily available and reliable food source.
2. Urtica massaica (Stinging Nettle)
Despite its stinging hairs, Urtica massaica is a key component of the gorilla’s leafy diet. These tall nettles are rich in essential nutrients, especially protein, calcium, and iron, which are important for growth and maintaining body strength. Gorillas have thick skin on their hands and tough lips and palates, allowing them to consume nettles without discomfort. This plant grows abundantly in moist, high-altitude areas and provides year-round nourishment. Female gorillas and nursing mothers particularly benefit from the iron-rich leaves, making it an essential part of the diet across all age groups.
3. Peucedanum spp. (Wild Celery)
Peucedanum, or wild celery, is a favorite leafy plant among mountain gorillas, especially in Bwindi and the Virunga Mountains. These celery-like herbs grow in the understorey of montane forests and offer crunchy stems with soft, flavorful leaves. Gorillas are often observed stripping off the leaves and chewing the juicy stalks. Wild celery is mineral-rich, containing potassium, calcium, and vitamins, which support healthy muscle function and overall vitality. Its abundance and palatability make it a staple in the daily foraging routine of gorilla groups.
4. Rubus spp. (Wild Blackberry)
Rubus plants, known for their prickly stems and sweet berries, also provide nutritious leaves that gorillas consume year-round. The leaves are soft and palatable, while the plant itself is a resilient species that thrives in forest edges, clearings, and disturbed areas. Gorillas typically browse the leaves even when the berries are not in season. During fruiting periods, they also enjoy the berries, adding variety and sugar to their otherwise fiber-heavy diet. The leaves, however, remain a constant food source and are particularly important during dry months when other food options are limited.
5. Thistle (Carduus or Cirsium spp.)
Thistles might appear unlikely as gorilla food due to their spiny leaves and stems, but gorillas are adept at stripping away the outer spines to access the tender inner leaves. These plants grow in clearings and open spaces within the forest and offer fibrous, nutritious leaves. Thistles are high in dietary fiber and can serve as a fallback food during dry seasons or food-scarce periods. The ability of gorillas to handle such challenging plants showcases their adaptability and dietary breadth within their mountainous habitat.
6. Mimulopsis spp.
Mimulopsis is a fast-growing herbaceous plant commonly found in disturbed or regenerating forest zones. These plants have broad, soft leaves that are easy for gorillas to grasp and chew. The leaves contain a high moisture content and are gentle on the digestive system. Because Mimulopsis grows rapidly in cleared or recently disturbed areas, it becomes an important food source where forest regeneration is taking place. Gorillas play a role in this ecological process, as they often frequent these areas and aid in seed dispersal.
7. Commelina spp. (Dayflower)
Commelina, commonly called dayflower, is a creeping herb with striking blue flowers and succulent leaves. It thrives in moist environments such as forest floors and along streambeds. The soft, watery leaves of Commelina are especially valuable to gorillas for hydration and easy digestion. These plants are consumed whole, including stems and leaves, and offer a mild taste that complements other more fibrous greens. Gorillas are known to seek out Commelina during warm weather, when the extra moisture helps regulate their body temperature.
8. Acanthus pubescens
Acanthus pubescens is a shrubby plant with large, hairy leaves that grow in the forest understory and open clearings. The leaves are rich in fiber and offer substantial bulk to the gorilla’s leafy diet. Although not as soft or juicy as some other plants, Acanthus plays a key role in digestion and is often eaten alongside more palatable greens. Its large leaf surface makes it an efficient foraging choice, allowing gorillas to gather a significant volume of food with minimal effort.
9. Urera spp. (Forest Nettle)
Urera, often referred to as forest nettle, is another stinging plant that gorillas consume despite its defensive hairs. Like Urtica, it is rich in iron and minerals, making it especially valuable for females and infants. Gorillas carefully pluck the young leaves, which are more tender and less irritating. These plants thrive in mid-elevation forests and are a common sight along forest trails and clearings. Urera serves both a nutritional and medicinal purpose, helping gorillas maintain a balanced intake of essential minerals.
10. Triumfetta spp.
Triumfetta is a group of shrubby plants recognized by their sticky burs and small leaves. Although they are not a primary food source, the leaves of Triumfetta are occasionally consumed, especially when more preferred plants are less available. They provide a dose of calcium and trace minerals, supplementing the diet rather than dominating it. Gorillas tend to consume these plants in smaller quantities, often as part of a broader mixture of leaves and herbs collected during foraging.
Stems and Shoots in the Gorilla Diet
Gorillas use their powerful hands and teeth to strip, snap, and chew these tough plant parts with ease, often consuming large quantities to meet their dietary needs. Their digestive systems are well-adapted to fermenting and processing fibrous plant matter, allowing them to extract maximum nutrients from each stem or shoot.
The following are key stems and shoots that gorillas frequently consume in the wild:
1. Bamboo Shoots (Yushania alpina)
Bamboo shoots are a highly prized seasonal delicacy among mountain gorillas, especially in the Virunga and Bwindi forests. These young, tender shoots emerge during the rainy season and are packed with water and essential nutrients, including carbohydrates, potassium, and fiber. Gorillas use their strength to snap off the base of the shoot, strip away the tough outer layer, and chew the soft, juicy inner core. These shoots provide a burst of energy and hydration and are often eaten in large quantities when in season. The availability of bamboo can even influence gorilla group movements and feeding patterns.
2. Celery-like Stems (Peucedanum spp.)
The same Peucedanum plants that provide edible leaves also offer succulent, crunchy stems that gorillas relish. These stems are often consumed with or without the leaves, depending on their maturity. Gorillas skillfully harvest the stalks, sometimes stripping off the fibrous edges before chewing. The water content in these stems helps maintain hydration, and the pleasant flavor makes them a regular part of the foraging routine. Their widespread presence in highland forests ensures a steady supply year-round.
3. Wild Ginger Stems (Aframomum spp.)
Aframomum, a relative of cultivated ginger, is a tropical forest plant that gorillas feed on for both its stems and fruits. The young stems are aromatic and soft, containing juice and fiber. Gorillas chew these stems not only for nutrition but possibly for their mild medicinal and digestive properties. These plants grow in moist, shaded areas along forest floors and are often found near streams and swamps. In addition to nourishment, some researchers believe the aromatic compounds may have antimicrobial effects in the gorilla’s digestive tract.
4. Thistle Stems (Carduus or Cirsium spp.)
After carefully removing the spiny outer leaves, gorillas often consume the soft inner stems of thistle plants. These stems are fibrous but tender enough for gorillas to chew and digest easily. Thistle stems are rich in cellulose, which supports the microbial fermentation processes in the gorilla’s large intestine. While not as juicy as bamboo or celery-like plants, thistles are valued for their bulk and are often consumed during dry seasons or in degraded forest areas where other plants may be scarce.
5. Nettles (Urtica massaica and Urera spp.) – Young Stalks
Gorillas don’t limit themselves to the leaves of nettles—they also eat the tender, young stalks. Despite the stinging hairs, these plants are consumed whole when young and soft. The stems are particularly rich in iron and calcium, and their high moisture content helps with hydration. The gorillas’ technique of folding or rolling the plants in their mouths helps neutralize the sting. This plant part is especially important for pregnant or lactating females who need more minerals to support reproduction.
6. Marantochloa spp. (Arrowroot Relatives)
Marantochloa species are large-leafed understory plants related to arrowroot and bananas. Gorillas often strip the outer fibers of the fleshy petioles (leaf stalks) and eat the inner portions, which are juicy and easy to chew. These stems are rich in starch and water and are especially helpful in balancing the high-fiber portions of the gorilla diet. The abundance of Marantochloa in some forest zones makes it a key fallback food when more seasonal delicacies like fruits or bamboo shoots are not available.
7. Rubus spp. (Wild Blackberry Canes)
While better known for their leaves and fruits, Rubus species (wild blackberries) also have tender canes that young gorillas and juveniles often chew on. These canes are soft when young and contain sap that adds both hydration and minerals to the diet. Older gorillas tend to focus more on the leaves and berries, but the shoots are valuable for their availability in disturbed or regenerating forest zones.
8. Acanthus pubescens – Soft Stalks
The large, coarse leaves of Acanthus pubescens are often accompanied by fibrous yet consumable stalks that gorillas ingest whole or in strips. While not the tastiest option, these stalks help increase dietary bulk and support gut health through their fiber content. They are commonly eaten alongside more succulent stems to round out the gorilla’s daily foraging intake.
Fruits that Gorillas Feed on
Fruits provide gorillas with essential sugars, vitamins, antioxidants, and hydration, giving them an energy-rich supplement to their leafy, fibrous meals. Unlike chimpanzees, gorillas do not often climb high into trees for fruit, but they will travel long distances on the ground to forage from fruiting shrubs and fallen tree fruits. Some gorillas in high-altitude areas like Bwindi or Virunga may only have access to fruit seasonally, but they still prioritize it when available.
1. Figs (Ficus spp.)
Figs are a keystone food source for many primate species, and gorillas are no exception. These soft, nutritious fruits are rich in simple sugars, calcium, and antioxidants. Ficus species produce fruit asynchronously, meaning some trees bear fruit at different times, providing a year-round supply. Gorillas consume both ripe and unripe figs, depending on availability. They eat them whole, often along with parts of the fig branch or leaves. Figs are particularly important for western lowland gorillas, who inhabit fruit-rich tropical forests.
2. Wild Berries (Rubus spp.)
These include wild relatives of blackberries and raspberries, commonly found in disturbed or regenerating forest areas. Gorillas carefully pick and consume the soft, juicy berries and sometimes chew on the tender shoots. The berries are packed with vitamin C and natural sugars, offering a quick energy boost. Juvenile gorillas are often observed enthusiastically foraging for berries, showing early foraging skills in these sweet treats.
3. Aframomum Fruits (Aframomum spp.)
In addition to their edible stems, Aframomum plants (wild relatives of ginger) produce bright red or orange fruits with aromatic seeds. Gorillas peel open the husks to access the sweet and spicy pulp around the seeds. These fruits may offer antimicrobial benefits and support digestion. Their unique flavor and juicy texture make them a favorite during the fruiting season.
4. Landolphia spp. (Wild Grapes)
These vine-growing fruits resemble small grapes and are rich in vitamins and hydration. Gorillas forage these from the forest understory or from low vines, chewing the pulp and spitting out the seeds. Landolphia fruits are especially important for western lowland gorillas, and are often shared between group members in a relaxed, social setting.
5. Musanga spp. (Umbrella Tree Fruits)
The umbrella tree, a fast-growing pioneer species in disturbed forests, produces small, round fruits that grow in clusters. These are rich in carbohydrates and minerals, making them a preferred food for both gorillas and monkeys. Gorillas often climb lower branches to access the fruit or forage fallen fruit on the forest floor.
6. Trema orientalis (Pigeonwood)
This species yields tiny, dark purple fruits that are highly attractive to gorillas during fruiting seasons. These fruits are high in energy and often eaten in large numbers. Trema trees also serve as shade providers and regrowth indicators in secondary forests, meaning they often grow where gorillas can easily find them.
7. Maesopsis eminii (Musizi Tree Fruits)
While not as commonly eaten as figs or berries, the fruits of the Musizi tree are consumed when ripe and available. These small, reddish-brown fruits offer a mix of fiber and sugars and are commonly found in mixed tropical forests. Gorillas have been seen foraging from the ground or climbing lower branches for access.
8. Syzygium spp. (Waterberry/Wild Guava)
These small, round, juicy purple or red fruits are highly nutritious and refreshing. They are abundant in both primary and secondary forests, particularly near swampy or riparian areas. Gorillas chew and swallow the fruit whole, and may also nibble on the leaves or twigs of the plant. The high water content makes Syzygium fruits particularly useful during dry spells.
9. Annona spp. (Wild Custard Apple Relatives)
Though not always widely available, gorillas do eat wild annona-like fruits when they find them. These fleshy fruits are rich in carbohydrates and fats, making them an energy-dense meal. Their soft pulp and rich aroma make them attractive, especially to adult gorillas who require higher energy intake.
10. Dombeya spp. (Forest Apple)
These small, sweet fruits are picked from low branches or foraged from the ground. Their sugar-rich pulp and edible outer covering make them appealing, particularly for gorillas living in lower altitudes. Gorillas eat them whole or split them with their hands and teeth.