Manatees are large, gentle aquatic mammals known for their slow-moving, herbivorous nature. Averaging 10 feet long and 1,200 pounds, these creatures maintain healthy aquatic ecosystems by grazing on seagrass. Their unique characteristics raise questions about their future.
Current Conservation Status
The West Indian manatee (including the Florida subspecies) is listed as threatened under the U.S. Endangered Species Act (ESA), reclassified from endangered in 2017. The International Union for Conservation of Nature (IUCN) Red List classifies all three manatee species—West Indian, West African, and Amazonian—as vulnerable.
Despite ESA downlisting, manatees face significant challenges, highlighted by an Unusual Mortality Event (UME) along Florida’s Atlantic coast. This event caused over 1,100 manatee deaths in 2021 and more than 800 in 2022, primarily from starvation. The U.S. Fish and Wildlife Service (USFWS) began a five-year review in 2021, proposing in January 2025 to separate the Florida and Antillean manatee subspecies. The Antillean manatee may be reclassified as endangered, though Florida populations have stabilized.
Major Threats to Manatees
Manatees face dangers, primarily from human activities. Boat strikes are a leading cause of mortality, accounting for 20-25% of reported deaths. Approximately 96% of adult Florida manatees bear scars from these collisions.
Manatees are vulnerable due to their slow speeds (three to five miles per hour) and preference for shallow waters. Their long, flat lungs, positioned along their spine, are susceptible to severe internal injuries from propeller cuts or blunt force trauma. They may also struggle to detect approaching boats, especially in shallow areas where low-frequency engine sounds can be distorted.
Habitat loss and degradation, particularly declining seagrass beds, are a significant threat. Pollution from agricultural runoff, wastewater, and coastal development contributes to the loss of these vital underwater meadows. For instance, the Indian River Lagoon has lost over 50% of its seagrass since 2011, leading to starvation events.
Harmful algal blooms (red tide) severely impact manatees. Caused by Karenia brevis algae, these blooms produce neurotoxins (brevetoxins). Manatees ingest these toxins by consuming contaminated seagrass or inhale them when surfacing. Exposure can lead to seizures, loss of coordination, and drowning.
Cold stress is a natural threat exacerbated by habitat changes. Manatees are tropical mammals sensitive to water temperatures below 68°F (20°C). Prolonged cold exposure can lead to a hypothermia-like condition, weakening immune systems and causing severe health issues. Historically, manatees relied on natural warm-water springs for refuge, but many are now inaccessible or degraded. Manatees frequently depend on warm-water discharges from power plants, creating vulnerability if these artificial sources are removed.
Entanglement in fishing gear and marine debris also endangers manatees. These materials can cause injuries or restrict movement, hindering a manatee’s ability to forage or escape danger.
Efforts to Protect Manatees
Manatees are protected by federal laws like the Endangered Species Act and Marine Mammal Protection Act. State legislation, such as the Florida Manatee Sanctuary Act, also provides protection.
Manatee Protection Zones, with specific speed limits and no-wake restrictions, reduce boat collision risks. These zones protect manatees in areas where they gather or travel. Some areas are also designated as sanctuaries, offering undisturbed safe zones, especially during colder months.
The Manatee Rescue & Rehabilitation Partnership (MRP) coordinates the rescue, rehabilitation, and release of sick or injured manatees. This collaborative effort involves agencies, organizations, and oceanaria, including SeaWorld and ZooTampa. Injured manatees receive medical care before returning to the wild.
Habitat restoration projects address declining seagrass beds and natural warm-water refuges. During severe seagrass shortages, supplemental feeding programs (e.g., distributing romaine lettuce) prevent starvation.
Public awareness campaigns educate boaters and the public about responsible interactions and conservation. The USFWS also proposed revising critical habitat designations, aiming to protect nearly two million acres for Florida and Antillean manatees.
Ways to Support Manatee Conservation
Individuals can contribute to manatee conservation. Responsible boating practices include obeying speed zones, vigilance for manatees, and staying in deep-water channels to avoid shallow seagrass beds. Polarized sunglasses help boaters spot manatees by reducing glare. Before starting a vessel, check the surrounding water for manatees.
Report injured, sick, or dead manatees to authorities like the Florida Fish and Wildlife Conservation Commission (FWC). Reducing pollution by properly disposing of trash and fishing gear, and minimizing fertilizers and pesticides that contribute to harmful algal blooms, benefits manatee habitats.
Support manatee conservation organizations through donations or volunteering; this funds rescue efforts, habitat restoration, and educational programs. Never feed or offer water to wild manatees, as this alters their natural behaviors and makes them vulnerable to human-related dangers.