Manatees, often called “sea cows,” are large, gentle aquatic mammals found in warm coastal waters. Their specialized skin is a significant adaptation, playing a multifaceted role in their survival, from sensory perception to healing from injuries.
Physical Characteristics and Texture
Manatee skin is grayish-brown, resembling an elephant’s hide. This thick, tough skin features numerous wrinkles and folds, which can make young manatees appear older. It is sparsely covered with fine, bristle-like hairs, distinct from the prominent whiskers on their snout.
West Indian manatees, including the Florida manatee, have three to four nails on each flipper. However, Amazonian manatees and dugongs lack these nails and have smoother skin. The overall texture is leathery and finely wrinkled, with a continuous flaking off of the outer layer.
Specialized Functions of the Skin
The sparse body hairs, or vibrissae, covering a manatee’s body are highly specialized sensory receptors. Each body hair is connected to a blood sinus beneath the skin, making them sensitive to water motion. This allows manatees to detect subtle hydrodynamic changes, assisting them in navigating murky waters and locating objects, similar to the lateral line system in fish.
Beyond sensory perception, the manatee’s thick, tough skin provides protection against abrasions and minor injuries. This durable outer layer is reinforced with densely woven collagen fibers, offering a strong barrier. The skin also plays a role in thermoregulation, helping manatees manage their body temperature. Manatees can adjust blood flow to their extremities and use thickened skin to reduce heat loss in cooler waters.
Algae Growth and Remarkable Healing
Manatee skin often hosts algae. This green growth is common on their backs, especially for manatees in freshwater, due to their slow movement and frequent resting near the surface, which exposes them to sunlight. Algae does not harm manatees; it may even offer some protection against ultraviolet rays.
Manatee skin has impressive regenerative capabilities, allowing effective healing from injuries, including severe boat strikes. These injuries, ranging from superficial lacerations to deep wounds, often leave recognizable scar patterns. Healed scars may appear smoother than surrounding skin, with colors like pink, white, or yellow, and can eventually be covered by dark, pigmented epidermis. This ability to recover from extensive trauma highlights the robust nature of their skin and its healing mechanisms.