Physical Characteristics

Manatee

Physical Characteristics

Size

  1. Adult West Indian and West African manatees average about 3 m (10 ft.) in length. Large individuals may reach lengths of up to 4 m (13 ft.). Average adult weights are approximately 363 to 544 kg (800-1,200 lb.). One particularly large Florida manatee weighed 1,655 kg (3,650 lb.). Females are generally larger than males.
  2. Adult West Indian manatees average about 3 m (10 ft.) and
    weigh approximately 363 to 544 kg (800 to 1,200 lb.).

  3. Amazonian manatees are the smallest of all three species. They are shorter and more slender. The longest specimen measured 2.8 m (9.2 ft.). A large individual weighed 480 kg (1,058 lb.).

Body Shape

  1. The manatee's body is streamlined-full around the middle and narrowing to a paddle-shaped tail.

Coloration

  1. The true color of a manatee is gray, although it may appear brownish-gray.
  2. Amazonian manatees usually have white or pink patches on the belly and chest.
  3. Organisms such as algae, which may grow on the skin of slow-moving individuals, alter the body color and make some manatees look more green or brown.

Pectoral Flippers

  1. ASDF
  2. Manatees have small, flexible pectoral flippers that are used for
    steering, touching, scratching, and even embracing.

  3. West Indian and West African manatees have three or four fingernail-like the toenails on an elephant's feet-at the tips of their flippers. Amazonian manatees lack fingernails.
  4. Manatee flippers have five digits that are covered by a thick layer of skin. This bone structure is similar to that of toothed whales, seals, and sea lions.

Hind Limbs

  1. Hind limbs are absent. Vestigial pelvic bones, which are not connected to the vertebral column, are found deep in the pelvic musculature.

Head

  1. Manatees have no external discernable neck.
  2. Manatees do not have external ear flaps. The tiny opening to the ear canal is located several centimeters behind the eye.
  3. The nostrils lie at the end of the snout on the upper surface. They close automatically when a manatee submerges.
  4. Manatee nostrils close automatically when it submerges.

  5. Manatees have a large flexible upper lip. Their lips help guide vegetation into the mouth. Vibrissae (whiskers) are found on the surface of the upper lip. Each vibrissa is separately attached to nerve endings and has its own supply of blood.
  6. Manatees have large, flexible upper lips that are used to
    guide food into their mouths.

  7. Small eyes (about 2 cm or 0.8 in. in diameter) are located on the sides of the head. The iris has a color ranging from blue to brown (Griebel and Schmid, 1996).
  8. A manatee's only teeth are 24 to 32 molars located in the back of the mouth. The front molars in each row are continually being worn down by the abrasive plants the manatee eats. As the teeth wear down, new molars grow in the back of the mouth and gradually move forward. The replacement process continually provides new chewing surfaces as the teeth wear down, and continues throughout the manatee's lifetime. This unusual dental adaptation is found only in the modern manatees, suggesting that the manatee diet at an earlier time was extremely abrasive.
  9. The front molars in a manatee's mouth are continually worn
    down by the abrasive plants it eats.

  10. In addition to molars, manatees have horny, ridged pads at the front of the upper and lower jaws which aid in crushing plant materials.

Tail

  1. The tail is evenly rounded and forms a paddle shape.
  2. Manatees have rounded, paddle-shaped tails.

  3. A manatee swims by moving its large paddle-like tail in an up-and-down motion.

Hair

  1. A manatee has sparse hairs scattered over its body, with the largest concentration around the snout area.

Manatees have a concentration of hairs around their snouts as well as
scattered over their bodies. A substantial nerve network transmits
tactile information from these vibrissae to the brain.