Manatees are marine mammals.Manatees are mammals |
that live in warm fresh water and seawater.Heavy herbivores
Manatees weigh about 1,200 pounds and measure around ten feet in length. All manatees are herbivores, they eat plants. In fact, they can eat up to 100 pounds or 10 to 15 percent of their body weight each day. Florida manatees, a subspecies of the West Indian manatee, dine on manatee grass, turtle grass, and water hyacinth.
Moving Molars
A feeding manatee uses its front flippers and muscular upper lips to bring plants to its mouth. Because it has not front teeth, the manatee relies on the thick, ribbed pads in the front of its mouth to help break vegetation into small, chewable pieces. Manatees have an endless supply of molars. A manatee may have six to seven functional molars on each side of its jaw. These grinding teeth form in the rear of the jaw and move forward. As older molars in the front become worn, they fall out and are replaced by new teeth.
Manatee mothers
A female manatee or cow can give birth to a single calf every three years. The calf begins feeding on plants when it's a few weeks old, but continues to nurse from its mother for about 12 to 18 months. Twins are rare.
This long period of nursing allows the calf to learn migration routes, foods, and preferred feeding areas from its mother. Manatees are mostly solitary creatures, but they sometimes gather in unorganized groups of a dozen or more.
Staying submerged
Manatees are usually found at or near the surface. The deepest recorded dive by a West Indian manatee is about 10 m (33 ft.). On average, manatees return to the surface every two to three minutes for air, but can stay underwater for up to 20 minutes. Manatees can renew about 90% of the air in their lungs in a single breath (humans renew only about 10%).
Manatee migration
All species of manatee migrate during particular seasons. West Indian manatees migrate to areas with warmer waters when water temperatures drop below 20°C (70ºF). Historically, these manatees migrated south, however many manatees now migrate to power plant outfalls and other manmade, warm-water discharges. In dry seasons, West African and Amazonian manatees migrate downstream or into deeper parts of rivers and lakes to avoid starvation and predation.
Manatee mortality
It's estimated that as few as 1,900 Florida manatees remain in Florida waters. About ten percent die each year. How do they die? Besides natural causes of death, many are injured and killed in accidents involving boats (boat impact and propellers cause severe injuries). Entanglement, ingesting garbage in the water such as fishing line and hooks, habitat destruction, and poaching are other threats to the manatee's survival. If they continue to die at this rate, this endangered species could become extinct in the next few decades.
What You Can Do for Manatees
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