The capybara, the world’s largest rodent, is native to South America and thrives in the Amazon rainforest’s humid, lush environments. These semi-aquatic mammals are frequently found along riverbanks, lakes, and floodplains, where they access abundant food sources. Their herbivorous nature means their diet is entirely plant-based. Capybaras primarily graze during the early morning and late evenings, often resting during the hottest parts of the day.
Primary Forage: Grasses and Aquatic Plants
Capybaras primarily consume various grasses and aquatic vegetation found in their riparian habitats, such as water hyacinths, sedges, and other herbaceous plants. An adult capybara can consume between 6 to 8 pounds (2.7 to 3.6 kilograms) of fresh grass daily. These plants are abundant, providing a consistent and readily available food source that supports their large size and energy demands.
Around 70-75% of their diet is composed of just a few plant species. Specific examples include sedges (Cyperaceae), switchgrass (Panicum grumosum), Bermuda grass (Cynodon), and crowngrass (Paspalum). These plants are staple components of the capybara’s diet.
Seasonal Dietary Shifts and Supplementary Foods
The capybara’s diet shifts with the changing seasons in the Amazon. During the wet season, when fresh grasses and aquatic plants are plentiful, capybaras are more selective. During the dry season, as fresh grasses and water plants become less available, their diet diversifies.
During these drier periods, capybaras consume reeds, grains, melons, squashes, fruits, and tree bark. Tree bark provides essential nutrients and helps maintain their continuously growing teeth. Capybaras also practice coprophagy, consuming their own feces. This behavior allows them to reabsorb nutrients and beneficial microbes from their food that were not fully digested the first time.
Specialized Digestive System and Feeding Behavior
Capybaras possess a specialized digestive system to process their fibrous, plant-based diet efficiently. They are hindgut fermenters, meaning that microbial fermentation of plant material occurs in their large cecum. The cecum, a chamber at the junction of the large and small intestines, is highly developed and can constitute a significant portion of their total digestive tract volume. Within this acidic environment, bacterial populations thrive, breaking down indigestible plant molecules like cellulose into usable nutrients.
Their feeding behavior involves extensive grazing, utilizing their continuously growing, strong teeth to crop and grind tough plant material. Their jaw hinge allows for a back-and-forth grinding motion, aiding in the breakdown of fibrous plants. This combination of specialized anatomy and behavior allows capybaras to extract maximum nutrition from the abundant vegetation in their Amazonian habitat, even from plants with low nutritional content.