- Direct take: Manatees are sometimes hunted for food, their oil, and their body parts. They can also be killed accidentally when they become entangled in fishing gear or boat propellers.
- Habitat loss and degradation: Manatees rely on shallow, warm waters with abundant seagrass for food and shelter. As coastal habitats are developed for residential and commercial use, these areas are lost and degraded, making it difficult for manatees to survive.
- Water pollution: Manatees are sensitive to pollution, which can enter their bodies through ingestion or skin absorption. Pollutants such as pesticides, fertilizers, oil, and sewage can cause illness and death in manatees.
- Vessel traffic: Manatees can be struck and killed by boats. They are especially vulnerable to injury from large, fast-moving vessels, such as cargo ships and speedboats.
In addition to these direct human causes of death, manatees are also affected by climate change, which can disrupt their food supply and make them more vulnerable to disease.