Manatees (/ˈmænətiːz/, family Trichechidae, genus Trichechus) are large, fully aquatic, mostly herbivorous marine mammals sometimes known as sea cows.

Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Amazon basin, and West Africa.

The etymology of the name is unclear, with connections having been made to Latin manus "hand" and to the term manaty "breast" from the Carib language of native South Americans.

The Sirenia are thought to have evolved from four-legged land mammals more than 60 million years ago, with the closest living relatives being the Proboscidea (elephants) and Hyracoidea (hyraxes).

The manatee has a large, flexible, prehensile upper lip, used to gather food and eat and for social interaction and communication.

[21] Social interactions between manatees are highly complex and intricate, which may indicate higher intelligence than previously thought, although they remain poorly understood by science.

[29] To be able to cope with the high levels of cellulose in their plant based diet, manatees utilize hindgut fermentation to help with the digestion process.

There are 6 to 8 high-crowned, open-rooted molars located along each side of the upper and lower jaw giving a total of 24 to 32 flat, rough-textured teeth.

Posterior molars erupt at the back of the row and slowly move forward to replace these like enamel crowns on a conveyor belt, similarly to elephants.

The coast of the state of Georgia is usually the northernmost range of the West Indian manatees because their low metabolic rate does not protect them in cold water.

[34] Manatees can travel hundreds of miles annually,[35] and have been seen as far north as Cape Cod, and in 1995[36] and again in 2006, one was seen in New York City[37] and Rhode Island's Narragansett Bay.

[45][46] Population viability studies conducted in 1997 found that decreasing adult survival and eventual extinction were probable future outcomes for Florida manatees unless they received more protection.

[49] As of 2022, a new manatee habitat was discovered by Klaus Thymann within the cenotes of Sian Ka'an Biosphere Reserve on the Yucatán Peninsula.

[51] The freshwater Amazonian manatee (T. inunguis) inhabits the Central Amazon Basin in Brazil, eastern Perú, southeastern Colombia, but not Ecuador.

[16] When threatened, the manatee's response is to dive as deeply as it can, suggesting that threats have most frequently come from land dwellers such as humans rather than from other water-dwelling creatures such as caimans or sharks.

[54] Their slow-moving, curious nature, coupled with dense coastal development, has led to many violent collisions with propeller-driven boats and ships, leading frequently to maiming, disfigurement, and even death.

Many manatees have been cut in two by large vessels like ships and tug boats, even in the highly populated lower St. Johns River's narrow channels.

[21] In an example, they cited one case study of a small calf "with a severe dorsal mutilation trailing a decomposing piece of dermis and muscle as it continued to accompany and nurse from its mother ... by age 2 its dorsum was grossly deformed and included a large protruding rib fragment visible.

Minimization of this injury is explicit in the Recovery Plan, several state statutes, and federal laws, and implicit in our society's ethical and moral standards.

[61][62] Another cause of manatee deaths are red tides, a term used for the proliferation, or "blooms", of the microscopic marine algae Karenia brevis.

[64] The bloom was present from early March to the end of April and killed approximately 15% of the known population of manatees along South Florida's western coast.

Fish and Wildlife Service began a feeding program to address the situation by distributing 3,000 pounds (1,361 kg) of lettuce per day to save the malnourished animals.

and are occasionally killed by entanglement in fishing gear, such as crab pot float lines, box traps, and shark nets.

Fish and Wildlife Service (FWS) does not consider the West Indian manatee to be "endangered" anymore, having downgraded its status to "threatened" as of March 2017.

The reclassification was met with controversy, with Florida congressman Vern Buchanan and groups such as the Save the Manatee Club and the Center for Biological Diversity expressing concerns that the change would have a detrimental effect on conservation efforts.

The MV Freedom Star and MV Liberty Star, ships used by NASA to tow Space Shuttle Solid Rocket Boosters back to Kennedy Space Center, were propelled only by water jets to protect the endangered manatee population that inhabits regions of the Banana River where the ships are based.

These include three government-run critical care facilities in Florida at Lowry Park Zoo, Miami Seaquarium, and SeaWorld Orlando.

[90] Snooty died suddenly two days after his 69th birthday, July 23, 2017, when he was found in an underwater area only used to access plumbing for the exhibit life support system.

The South Florida Museum's initial press release stated, “Early indications are that an access panel door that is normally bolted shut had somehow been knocked loose and that Snooty was able to swim in.”[91] Since the 19th century, Georgetown, Guyana has kept West Indian manatees in its botanical garden, and later, its national park.

But as these pig-fish are a noisy, contemptible set, mostly lurking in the mouths of rivers, and feeding on wet hay, and especially as they do not spout, I deny their credentials as whales; and have presented them with their passports to quit the Kingdom of Cetology.