Kangaroos, iconic marsupials of Australia, have developed remarkable strategies to thrive across diverse habitats, from lush coastal areas to arid inland regions. While often thought not to drink water, kangaroos do, but their biology allows for significant adaptability in how they acquire and conserve it. Their survival hinges on direct water consumption, efficient extraction from their diet, and specialized physiological and behavioral adaptations.
Direct Drinking Sources
Kangaroos readily drink water when available, lapping it up like many other mammals. They seek natural sources such as rivers, creeks, and waterholes. After rainfall, temporary puddles also become accessible. In arid conditions, they may dig shallow holes in dry riverbeds or sandy areas to reach subsurface water. Kangaroos drink less frequently than many large mammals like cattle or sheep, often finding sufficient hydration by drinking every couple of days.
Hydration from Diet and Metabolism
Kangaroos meet a significant portion of their water needs through the moisture in their diet. As herbivores, they primarily consume grasses, shrubs, and herbs, which can contain substantial water, especially during wetter seasons. Green vegetation, for instance, can be nearly 98% water. Their efficient digestive systems maximize water absorption from these plant materials. They may even regurgitate and re-chew food to extract additional water.
Kangaroos also produce metabolic water, a byproduct of breaking down carbohydrates, fats, and proteins for energy. This internal process contributes to their overall water balance. While a smaller contribution than water from food, metabolic water provides a supplementary source, especially beneficial during dry periods when other sources are limited.
Specialized Water Conservation
Kangaroos exhibit numerous adaptations to conserve water. Behaviorally, they are most active during cooler parts of the day—dawn, dusk, and night—to avoid intense midday heat. This activity reduces water loss through evaporation. During the hottest hours, they seek shade under trees, shrubs, or rock formations to lower body temperature and minimize water expenditure.
Physiologically, kangaroos have highly efficient kidneys that produce concentrated urine, minimizing water loss during waste excretion. They also have a low metabolic rate, which reduces overall water requirements. Unlike many mammals, kangaroos have fewer sweat glands and primarily rely on panting for cooling when at rest, rather than extensive sweating.
During periods of intense heat or exercise, they employ a unique cooling mechanism: licking their forearms. The saliva spread on their forearms, where blood vessels lie close to the thin skin surface, evaporates and cools the circulating blood.