The red kangaroo, a large marsupial, inhabits Australia’s arid and semi-arid interior, including grasslands, shrublands, and deserts. As the largest living marsupial, it has developed a specialized diet and adaptations to efficiently utilize vegetation and conserve water in its challenging environment.
What Red Kangaroos Primarily Eat
Red kangaroos are herbivores, primarily grazing on grasses and forbs. They prefer green vegetation, which constitutes a significant portion of their diet. In Central Australia, green grass accounts for 75 to 95 percent of their intake, with species like Eragrostis setifolia and Enneapogon avenaceus being dominant, along with various flowering plants.
When green grasses are scarce, such as during dry periods, red kangaroos consume dry grasses, forbs, and browse on shrubs and small trees. They eat chenopods like Bassia diacantha and Maireana pyramidata when preferred food sources diminish. Red kangaroos are selective feeders, choosing plants based on their nutritional value and moisture content. They forage during cooler hours to avoid the heat of the day.
How Red Kangaroos Digest and Obtain Water
Red kangaroos possess a specialized digestive system that efficiently extracts nutrients from tough plant material. Their stomach is divided into two main chambers: the sacciform and the tubiform. The sacciform forestomach contains microorganisms, including bacteria, fungi, and protozoa, which ferment plant matter and break down cellulose. This fermentation process can keep food in the forestomach for up to 16 hours, allowing for thorough digestion.
Like cows, kangaroos can regurgitate partially digested food to re-chew it, a process known as merycism, further aiding in nutrient extraction. This efficient digestive system also plays a significant role in their water acquisition. Red kangaroos primarily obtain water from the moisture content within the plants they consume. They can survive extended periods without drinking free water, relying on this dietary moisture. Physiological adaptations, such as producing concentrated urine and maintaining a low metabolic rate, help them conserve water in their arid habitat.
How Environment Affects Their Diet
Environmental conditions, particularly rainfall patterns, significantly influence the red kangaroo’s diet. During periods of abundant rain, red kangaroos have access to a wider variety of lush, green grasses and forbs, which are their preferred food sources. This availability of high-quality forage supports their populations.
During droughts, their diet becomes more restricted, forcing them to consume drier, less nutritious vegetation. They may shift to browsing on shrubs or seek green plants that persist near watercourses or in areas with recent localized rainfall. Red kangaroos are capable of traveling considerable distances in search of more favorable feeding grounds, showcasing their adaptability to changing food availability.