The capybara, the world’s largest living rodent, is a semi-aquatic mammal native to South America. These creatures inhabit wetlands and grassy areas near water sources like rivers, ponds, and marshes. They possess a robust, barrel-shaped body covered in short, brownish fur, a blunt snout with small ears, and almost no tail. Standing up to two feet tall at the shoulder and weighing between 77 to 146 pounds, their physical characteristics reflect their adaptability to both land and water.
Movement on Land
Capybaras navigate their terrestrial habitat with a deliberate, unhurried pace, typically walking or trotting. Their short, sturdy limbs support their considerable body weight, enabling them to move across various terrains. Though calm, these rodents can exhibit agility and speed when necessary.
When faced with perceived threats, capybaras can accelerate into a gallop, reaching speeds of up to 22 miles per hour (35 kilometers per hour) over short distances. This burst of speed is primarily a defense mechanism. Their hind legs are slightly longer than their forelegs, contributing to powerful propulsion during swift movements.
Their ability to make quick turns and sudden stops aids in evading danger on land. While not built for long-distance running, their terrestrial speed is sufficient to reach the safety of water or dense vegetation. This combination of a steady gait for daily activities and explosive speed for emergencies allows them to thrive.
Movement in Water
Capybaras are adept swimmers. Their partially webbed feet provide efficient propulsion, allowing them to glide through water with ease. They can swim both on the surface and fully submerged.
Water serves as a primary refuge from predators such as jaguars, anacondas, and caimans. Capybaras can remain completely submerged for up to five minutes to hide from threats or forage for aquatic vegetation.
They can even sleep in the water, keeping only their nostrils exposed for air. This behavior helps them regulate body temperature in warm climates and provides a secure resting place. Capybaras often graze on water plants, relying on aquatic ecosystems for both sustenance and safety.
Anatomical Adaptations for Movement
The capybara’s physical structure is well-suited for its dual existence on land and in water. Their feet feature partial webbing between their toes, a key adaptation for efficient movement in both environments. This webbing enhances their swimming abilities by providing greater surface area for propulsion, while also assisting in navigating soft, muddy terrain on land.
Their barrel-shaped body, measuring between 3.5 to 4.5 feet in length, contributes to their buoyancy in water, allowing them to float and maneuver with less effort. Short, powerful limbs provide strength for effective propulsion during swimming and stability for terrestrial locomotion. While their front feet have four toes, their hind feet have three, all equipped with strong, almost hoof-like claws.
The placement of their sensory organs—eyes, ears, and nostrils—high on their heads allows capybaras to remain largely submerged while still seeing, hearing, and breathing. This adaptation is beneficial for detecting predators and maintaining environmental awareness without fully exposing themselves.