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About Manatees

Manatees are curious marine mammals that spend their day eating, sleeping, and playing. It was the playing part that drew us to Central Florida to get a closer look at these shy sea cows. Many years ago we discovered that not only could you get a close-up view of these strange looking animals from above the water, but it was indeed possible to get in the water and snorkel with these gentle giants. We started researching and found that the Florida manatee, a subspecies of the West Indian manatee, ranges from the St John’s River south to around Miami on the Atlantic coast, and that they tend to congregate anywhere from the Everglades north to the Suwannee River on the Gulf Coast. Of most interest was the fact that they migrate to warmer waters during the winter months. They seek out as refuge from the cold, the warm spring fed waters of Crystal River, Weeki Wachee Spring, and Homasassa Spring, which are a constant 72 degrees Fahrenheit year round.  The best time to see the manatees gathering in the rivers is anywhere from October to April.

Facts about Manatees

Here are some interesting facts:

Common Name: West Indian Manatee, also know as "Sea Cow"
Scientific Name: Trichechus Manatees
Estimated Population: Fewer than 3,000
Range: Found throughout rivers, springs, and shallow coastal waters
                               of Florida and neighboring states
Population Status: Endangered
 

The average weight of a manatee is about 1200 pound (500 kg).  They grow up to 12 feet long.  Manatees hold their breath for 3 to 5 minutes when active and up to 20 minutes when resting.

A manatee eats as much as 10% of its body weight each day. Like whales, their large bodies can only be supported in their watery environment. On land, their body weight would crush their internal organs.

What weights over 1000 pounds, looks a bit like a walrus with wrinkled, gray-brown, spongy skin, is sometimes called a "sea cow", is related to an elephant, was mistaken for mermaids, can eat more than 100 pounds of vegetables per day, and travels an average of 3 to 5 miles per hour? Why the manatee, of course!

These large animals were once thought to be related to walrus because of the way they look. Today, scientists are able to identify animals using genetics. Now they know that manatees are more closely related to elephants than any other living animal. Scientists believe that manatees evolved from land mammals that returned to an aquatic life.

Manatees are the only marine mammals that are herbivores. Just to keep their big bodies warm, they have to eat up to one tenth of their body weight every day. For the typical manatee that means more than 100 pounds of water plants! That's equal to more than 200 heads of lettuce!

Keeping warm is a real problem for these animals. Their cylindrical bodies help conserve heat, but they don't have the blubber that other marine mammals do. Their metabolism is also very low, so they don't generate a lot of body heat. As a result, they can get sick when the water temperature falls below 70° F. In cold water, they can develop pneumonia, get too sluggish to eat, and can die. Most manatees live in warm, tropical waters, but Florida manatees live in sub-tropical waters that get below 70° F in the winter months (Dec. through Mar.). Manatees have a behavior which helps them survive the colder water. In the winter, they seek out the natural warm springs of Florida's coastal rivers. They even gather where electric power plants discharge warm water. To protect manatees, many of these areas are now Manatee Sanctuaries.

Manatees are well suited to their slow aquatic life. They have flexible front limbs that they use to steer as they swim. They can also use these limbs to hold their food. Their body ends with a large paddle shaped tail. With powerful up and down strokes, they use their tail to push them through the water. Usually they move along at 3 to 5 miles per hour, but when frightened, they can move more quickly

Like all mammals, manatees breathe air. As a marine mammal, they must rise to the surface to take a breath. While resting this happens every 20 minutes, but when they are active, they need to take a breath every 3 to 5 minutes. When people breathe, they only change about 10% of the air in their lungs. When manatees breathe, they change up to 90% of the air in their lungs. To do this, they exhale very hard when their nose breaks the surface, much like a whale or a person snorkeling will do. While they don't "spout" like a whale will sometimes do, there is often a cloud of mist. Breathing like this means there is more fresh oxygen in their lungs, and allows the animal to stay underwater longer between breaths. Manatees also have two other special breathing adaptations. They can only breathe through their nose, and their nostrils have special flaps that close tightly when they dive.

A manatee's mouth and teeth are specially adapted to an herbivorous life. They do not have front teeth, only special "marching" molars. Like elephants, they have 4 sets of 6 to 8 molars. As the front molar wears down from chewing on fibrous plants and sand, it is shed. The teeth behind it "march" forward as a new tooth emerges at the back. Without hands, it can be hard to get food to your mouth. To solve this problem, manatees have a large, split upper lip. The left and right sides can move independently to move the food into place. Last of all, behind the lips special ridged pads break food into smaller pieces before the molars finally grind it up.

Manatees are generally solitary animals. However, when a female is ready to mate, several males will gather around her forming a mating herd. After mating, they resume their solitary lives. There is, however, a strong bond between cow and calf. After birth, calves stay close to their mothers, and touching seems to be important to them. They nurse for nearly a year, and stay with their mother for up to two years.

At birth, manatee calves weight 70 pounds (30 kg) and are 50 inches (120 cm) long. They can live to be 70 years old, weigh as much as 2,000 pounds (500 kg), and be more than 12 feet (3 m) long. Reproduction is slow for manatees. Manatees are mature and able to breed at about 10 years of age. The gestation period is one full year for manatees, and cows give birth only once every 3 to 5 years.

Manatees communicate with each other with voices that sound like clicks and chirps. The sounds they make can be heard by humans. Communication is especially strong between a cow and her calf, and that helps the two remain in contact with each other.

Where to Find Manatees

In the Wild...

Blue Spring State Park, Orange City, FL
Crystal River Wildlife Refuge, Crystal River, FL
Florida Power and Light Plant, Fort Lauderdale, FL
Homosassa Spring, Homosassa, FL
Tampa Electric Company Big Bend Walk, Tampa, FL

In Captivity...

Disney World, Orlando, FL
Miami Seaquarium, Miami, FL
Nature World Attraction, Homosassa, FL
Sea World, Orlando, FL

Here is the range of the manatees throughout the world.

The rivers and springs around Crystal River and Homosassa Springs are among the few places in the world where divers can still interact with these rare marine herbivores. In the crystalline freshwater pool at Homosassa Springs, we’ve snorkeled among more than 20 manatees. It can be a little scary when a 1000-pound, 10-foot long critter starts sucking on one of your fins or decides to swim between your legs while you’re trying to take its picture. Manatees have total buoyancy and can swim sideways and upside down and can turn on a dime.

From November to March, the manatee leaves the frigid coastal waters to bask in the warmth of Florida’s many rivers and springs. During this peak season, sanctuaries such as those around Kings Bay in Crystal River host the largest winter gathering in Florida—as many as 300 manatees have been sighted in and around this area. Divers and snorkelers should also keep their eyes open for many varieties of freshwater fish. For non-divers, just relax and stay in the boat. With water this clear, you’ll have a "big picture" view of nearly all of the manatees in the spring. At local shops, you can buy an inflatable periscope-like device that also provides a more telescopic underwater view.

Everyone should experience the grace of these beautiful animals. We should work harder to protect them if more people had intimate interaction with the manatees. Just remember to operate your boat at idle and slow speed in areas where manatees are likely to be. This easy and simple rule, if followed, will help save these endangered animals.

Endangerment

Habitat loss, harassment, watercraft collisions, and accidental ingestion of discarded fishing line and other synthetic debris floating in water-ways are among the number of life-threatening hazards manatees face. There are several survival stories as well as sightings of the manatee that are shared among those who support the survival of the Manatee, as well as those who happen to sight them on their journey's. Last year in Florida alone, there were 87 Manatee rescues & releases. The Save the Manatee organization explores these and other issues in public-information campaigns and provides literature and brochures to citizens interested in helping to preserve the Manatee. A few of the survivor stories include a manatee named 'Moises' who is one of the many survivors whose life was extended because others cared. Another fascinating story involved the first neurological surgery ever performed on a Manatee named 'Nash'. This surgery was performed by a team of doctors at the Miami Seaquarium, founded by the Marine Life Preservation Society, and was marked as the first time in history that a neurosurgical procedure had ever been performed on an endangered marine mammal such as the Manatee. The survival and protection of the Manatee is dependent on various organizations, State parks, volunteers, grants, donations and government, along with the respect and kindness from humans.

Primary Causes of Death

watercraft collisions
crushed or drowned in storm or flood gates
vandalism and poaching
entrapment by man-made structures
cold stress
natural causes and loss of habitat
entanglement in lines and nets
crab trap entanglements
diseases and illnesses
birth complications
ingestion of hooks, lines, plastics and other pollutants
natural catastrophes and "red tide"

A word of caution: The manatee is an endangered species and is protected by strictly enforced state and federal laws. Prior to a dive tour or boat rental from one of the local dive shops, you’ll be required to review a video and brochure. Pay close attention. Violations can be costly—up to $100,000 and one year in prison. The single most important guideline for interacting with manatees is the same as with other wildlife—look, but don’t touch. Contact with manatees can be nearly as hazardous to their well-being as feeding or watering them. Frequent contact with humans can lead to behavior modifications, which reduces their natural fears and makes them even more susceptible to harm.

If you have questions, please call (205) 822-2121, fax us at (205) 822-2160 , or write us at info@scubaventuresinc.com