Florida Manatee - Isabella Davis

Florida Manatee
By Isabella Davis

 Photo credit: Animalia Life

Description and Ecology

The Florida Manatee (Trichechus manatus latirostris) is one of the two subspecies of West Indian Manatees. The Florida Manatee is characterized as a large, gray aquatic mammal with a body that tapers to a flat, paddle-shaped tail. They have two forelimbs with three to four nails on each flipper and a wrinkled head with whiskers on the snout. The average adult manatee is about 10 feet long, weighs between 800 to 1,200 pounds, and can live up to 60 years. This species is mainly herbivourious, however small fish and invertebrates may be ingested along with their normal vegetation including aquatic plants. Most of their time is spent eating, resting, and traveling. They may rest submerged at the bottom or just below the surface of the water, coming up to breathe on an average of every three to five minutes. 

Map by Jerome Cookson, National Geographic

Geographic Range and Population Changes

This species can be found in shallow, slow-moving rivers, estuaries, saltwater bays, canals, and coastal areas where seagrass beds or freshwater vegetation flourish. This species cannot survive in water temperatures that are colder than 68 degrees Farenheit due to their extremely low metabolic rate and lack of a thick layer of insulating body fat. Therefore they are a migratory species that need to always be in warm water. They are primarily found in Florida during winter months, and then migrate in summer to other parts of the United States, where they are commonly found along the coast of Alabama, Georgia, and South Carolina. This range has recently expanded as far as Texas and Massachusetts, as well as coast waterways through Central and South America. The species is divided into four management units (Northwest, Upper St. John' River, Atlantic, and Southwest.) According to the Florida Fish and Wildlife Conservation Commission, all four units are likely to decrease over the next few decades with the loss of warm water refuge

Main Threats

The leading human-caused threat to Florida manatees is collisions with boats. Propellers and boat hulls inflict serious or deadly wound. It is so common nowadays that most manatees have a pattern of scars on their backs or tails after surviving collisions with boats. The greatest long-term threat to manatees involves the loss of warm-water habitat that manatees need to survive. At temperatures below 68 degrees Fahrenheit, the stress of the cold can become dangerous, or even fatal. Over the past 10 years, Florida’s manatees have had higher-than-usual numbers of deaths from cold stress. According to Defenders of Wildlife, during the winter of 2010 there was 766 manatees killed, nearly 300 of them by an extended period of very cold weather. Scientists believe that unless these human caused deaths are controlled, the manatee population will not recover. It's predicted that there is about 6,100 individuals left today. 

Photograph by Paul Nicklen, National Geographic 

Listing Date and Type of Listing

Listed on October 20th 2001. This species is considered endangered under the Endangered Species Act. 

Recovery Goal 

The focus on the recovery plan is on implementing, monitoring, and addressing the effectiveness of conservation measures to reduce or remove threats. The goal is to assure the long-term viability of the Florida manatee in the wild, ultimately removing the species from the list of Endangered and Threatened Wildlife. This can be done by adopting and maintaining minimum springs flows, protecting warm-water refuge sites, protecting foraging habitat associated with select warm-water refuge sites, and reduce human caused deaths.

What Can You Do?

Since most deaths are human caused due to boat strikes and habit destruction, there are many ways in which we can help prevent more manatees from dying. Facilitating manatee recovery through public awareness and education is a good place to start. Once the word is spread, than action can begin to take place. Minimizing the causes of manatee disturbances and harassments is one way to ensure that this species will face less injury or mortality by humans. It is important to protect, identify, evaluate, and monitor manatee habits in order to help sustain this species. If more effort isn't made soon to protect this species, than there's a chance that the Florida Manatee will go extinct one day.

Sources

https://www.savethemanatee.org/manatees/manatee-population/

http://ashlandmarinebio.blogspot.com/2014/03/the-florida-manatee-ecology-conservation.html

https://ecos.fws.gov/docs/recovery_plan/011030.pdf

https://www.nrc.gov/docs/ML1224/ML12240A299.pdf

https://defenders.org/florida-manatee/threats

https://www.fws.gov/endangered/species/recovery-plans.html