Giraffes, the world’s tallest mammals, possess a distinctive dietary strategy. Their impressive stature allows them to access a unique food supply, primarily consisting of vegetation from trees and shrubs. This plant-based diet is supported by various physical adaptations.
The Giraffe’s Main Menu
Giraffes are herbivores, classified as browsers, meaning they primarily consume leaves, flowers, and fruits from woody plants. A significant portion of their diet consists of leaves and shoots from acacia species, which are highly nutritious despite their thorns. While acacia is a favorite, giraffes are adaptable eaters and can feed on over 100 different plant species, including mimosa and apricot trees. Adult male giraffes can consume up to 66 kilograms (145 pounds) of food daily.
The high water content in their preferred browse significantly reduces their need for frequent visits to water sources. They can obtain nearly all the moisture they require directly from their food, making them well-suited for arid environments. Occasionally, giraffes have been observed chewing on dried bones, a behavior known as osteophagy, likely to supplement their diet with calcium and phosphorus.
How Giraffes Get Their Food
The giraffe’s physical characteristics are well-suited for its browsing lifestyle. Their exceptionally long necks and legs enable them to reach foliage high in trees, minimizing competition with other ground-dwelling herbivores. A giraffe’s prehensile tongue, which can extend up to 45 centimeters (18 inches), is highly dexterous, allowing it to grasp and strip leaves from thorny branches. Their tough, flexible lips also provide protection against the sharp thorns commonly found on their preferred plants.
Once foliage is gathered, specialized molars efficiently crush the fibrous plant material, including any ingested thorns. Giraffes spend a considerable portion of their day actively foraging and eating. As ruminants, they possess a four-chambered stomach, which allows them to efficiently digest tough plant matter by regurgitating and re-chewing their food as cud throughout the day.
Diet Changes Through the Seasons
A giraffe’s diet changes considerably with the seasons, adapting to the availability and nutritional content of plants. During dry seasons, when succulent leaves and preferred browse might become scarce, giraffes diversify their diet. They may consume lower-quality vegetation, including woody stems, bark, and even fruits and flowers that are more abundant. This necessitates increased browsing time to meet their nutritional needs.
Conversely, the wet season brings a wider variety of lush, nutritious leaves, flowers, and fruits, allowing giraffes to select higher-quality forage. Female giraffes, particularly those nursing young, often exhibit selective feeding, choosing leaves with higher nutritional value and lower concentrations of compounds like tannins. These seasonal adjustments ensure giraffes maintain adequate nutritional intake throughout the year.