Manatees are large marine mammals that inhabit slow rivers, canals, saltwater bays, estuaries, and coastal areas. They are a migratory species, inhabiting the Florida waters during the winter and moving as far north as Virginia and into the Chesapeake Bay, sometimes seen as far north as Baltimore, Maryland and as far west as Texas in the warmer summer months. Manatees are calm herbivores that spend most of their time eating, sleeping, and traveling. They have a lifespan of about 60 years with no known natural enemies. Some of their deaths are the result of human activity. In the past, manatees were exploited for their meat, fat, and hides.

Various human activities threaten manatee populations. There is some cultural significance in certain areas of South America and the Caribbean that manatees have been used as a food source since pre-Columbian times. In these areas and the Amazon basin manatees are a center point of folklore and local myths since before European expansion. While manatees are not hunted as a food source in many areas there is a history of hunting and poaching in areas such as Brazil and the West Indies. Fishing nets and lines can cause injuries to manatees that can lead to serious infections. Studies have shown that around 14% of manatees since 1978 have been found with debris in their GI tract which mainly consisted of fishing lines. Some manatees have also been shown to have missing or scared fins due to their entanglement in these fishing lines.

Some manatee deaths are the result of collisions with boats. In a study done in Florida in 2002 it was found that collisions with boats makes up 25% of deaths of manatees but when surveyed the boaters in Florida responded positively to learning more about manatee conservation and their habits in boating areas. Additionally, fertilizer runoff, leaking septic tanks, waste water discharges can trigger algae blooms which kills off a lot of seagrass which manatees depend on for food. One study has found that metal concentration in the blood of manatees found in Florida and Belize needs to be studied and needs a baseline of metal concentrations. It was found that there were significant differences in certain metals such as copper and zinc for manatees in different areas as well as differences in wild and rehabilitating, captured manatees. These differences provide necessary information about the health of manatees for clinicians in rehabilitation centers in order to properly care for the manatees.

Manatees tend to gather in the warm water outflows of power plants and springs during cold weather. Manatees are not adaptable to colder waters, therefore, if they do not make it to warmer waters in time for winter they can undergo cold stress. These animals have an exceptionally low metabolic rate and poor insulation which in turns does not allow them to thermoregulate in cold waters. According to Florida Fish and Wildlife, the 2023 Preliminary Manatee Mortality Report shows that the main reasons for manatee mortality was boat collisions and cold stress. Manatees have shown in certain studies that manatee cognition is very good and that have much more complex social skills than previously known and requires more research to be done.

Starting in the 18th century when the English declared Florida a manatee sanctuary and made manatee hunting illegal, people have worked to protect this species. In 1893, manatees first received protection under Florida law, and in 1907 this law was revised to impose a fine of $500 and/or six months of jail time for assaulting or killing a manatee. In accordance with the Endangered Species Preservation Act of 1966, an act of Congress designed to list endangered animal species and offer them limited protection, the manatee became one of 78 original species listed as being threatened with extinction. There are currently more than 1300 species on this list. On March 11, 1967, federal efforts to protect the manatee began when the United States Fish and Wildlife Service listed the manatee as endangered on the ICUN Red List.

In 1972, the manatee was designated a marine mammal protected under the Federal Marine Mammal Protection Act. This act prohibited the removal of any marine mammal and imposed a fine of up to $2000 and/or one year in jail for doing so. The Endangered Species Act of 1969 was revised in 1973 and increased federal protection of manatees. The “act made it a violation to harass, harm, pursue, hunt, shoot, wound, kill, capture, or collect an endangered species…authorized cooperative agreements between states and the federal government with funding management, research and law enforcement.” This act also includes touching or feeding an endangered species. If manatees were getting fed from people, especially people on boats, that gives the manatee a positive reaction with people and boats and would more cause them to approach those things more. This in turn would cause further mortality form boat collisions and/or net entanglement.

In 1974, the Sirenia Project was established in Gainesville, Florida to provide manatee documentation and rescue programs. In 1976, Sea World of Florida began a Manatee Rescue and Rehabilitation Program. The Florida Manatee Sanctuary Act passed in 1978, amending the 1907 state law. Florida became an official refuge and sanctuary for the marine mammals, and the regulation of boat speeds in areas of manatee inhabitation became allowed. In that same year, the U. S. Fish and Wildlife Service, Florida Audubon Society, and Sea World also sponsored the “West Indian Manatee Workshop” in which six management recommendations were proposed: regulations to control boaters and divers, land acquisition for refuges, study of potential artificial refuges, explore technological control mechanisms to protect manatees, develop oil spill contingency plans, and increase public education.

In 1979, Florida Governor Bob Graham made November Manatee Awareness Month, and the first state-designated protection zones were established. The year 1980 saw Congress allocate $100, 000 to the Marine Mammal Commission and the development of the initial Federal Manatee Recovery Plan by the U. S. Fish and Wildlife Service. In 1981, Bob Graham and Jimmy Buffett formed the Save the Manatee Committee, the precursor of the Save the Manatee Club, which sought to protect manatees and their habitats. Both the Marine Mammal Protection Act and the Endangered Species Act were reauthorized in 1988 as various new groups, companies, and organizations began to invest time and resources in the protection of the manatee. The early 1990s saw more government money being allocated to the cause, more research being conducted, and more protection plans being implemented.