The hippopotamus, known as “Jalagainda” in Nepali, is an aquatic animal that stays submerged in water but cannot swim. Instead, it walks along the riverbed. A red, oily substance secreted from its skin acts as a natural sunscreen, moisturizer, and antibiotic, protecting it from skin infections. Hippopotamuses spend 16–18 hours a day in the water and come out at night to graze on grass, consuming up to 30–40 kilograms. Their aggressive behavior is driven by self-defense and competition within their territory.
Commonly called hippos, these water-dwelling creatures are called “Jalagainda” in Nepali. The Greek word “hippopotamus” means “river horse,” although their characteristics closely resemble those of whales and dolphins. These animals spend the day submerged and emerge at night to graze. Interestingly, despite living in water, they cannot swim but instead walk along the deep parts of rivers.
Among intriguing facts about the hippopotamus is the secretion of two types of red oily pigments from their skin — “hipposudoric acid” and “norhipposudoric acid.” These substances are initially colorless but turn red and then brown within minutes upon exposure to air and sunlight. They function as natural sunscreen, moisturizer, and antibiotic agents. Because their skin is extremely sensitive, direct exposure to sunlight can cause cracking and increase the risk of infection, a risk mitigated by this reddish coating. This unique adaptation distinguishes hippos from other animals.
Hippopotamuses spend 16–18 hours daily in water, usually inhabiting rivers, lakes, and swamps. The water prevents their sensitive skin from drying out and helps regulate body temperature. At night, they leave the water to eat up to 30–40 kilograms of grass. Although they cannot swim, their thick skin allows them to walk underwater, typically advancing by pushing off the riverbed with their feet. Additionally, their nostrils, ears, and eyes remain open even when submerged. Water is central to their existence, and drying up of water sources poses a serious threat to their survival.
