What Role Do Manatees Play In The Ecosystem?

Manatees are aquatic mammals that can live in saltwater and freshwater. The manatee biome includes slow-moving rivers, bays, estuaries and coastal marshes, preferring to stay in water that is about 7 feet deep. The North American manatee habitat and range goes from Florida and the Gulf of Mexico all the way up to waters off the coast of Massachusetts.

Manatees resemble a walrus in some ways but are relatives of the elephant. Manatees are an endangered species with estimates having no more than 3,000 individuals left in the wild.

Manatees are herbivores, meaning they consume only vegetation. Their role in the ecosystem is as a plant eater, as they feast on over 60 species of water vegetation in the waters they live in. As aquatic animals, the manatee biome is only found in marine and freshwater biomes.

Manatee species are found in the southern coastal waters of the United States, especially the waters off of Florida. Other manatee species are found in limited parts of interior eastern Africa and in South America.

They're also migratory species. This means that during colder months, manatees in North America waters are found mostly in Florida. In warmer months, you can find manatees in waters off the coast of Texas, Georgia, South Carolina and even as far up as Massachusetts.

Manatees are essentially 100 percent herbivorous. The occasional mollusk and other types of sea creatures may accidentally be consumed by the manatee as it feeds, but they do not actively pursue any fish or other marine or freshwater animals or organisms.

What They Eat

Manatees can weigh more than a thousand pounds and have been commonly been known to eat as much as 15 percent of their own body weight in plants each day. Manatees are the watery equivalent of deer, spending many of their waking hours grazing.

This makes them a primary consumer as they only eat plants like:

• Turtle grass
• Rice plants
• Mangrove leaves
• Manatee grass
• Algae
• Hydrilla

What Eats Them

Manatees have very few natural predators in their ecosystem. Sharks, alligators, crocodiles and killer whales are the only creatures large enough to handle a manatee, but attacks on them by these predators are rare. They are large enough to be left alone by just about every other animal they encounter except for man.

They have been hunted to the edge of extinction by people for their meat and bones and are extremely vulnerable to being hit by boat propellers, which kill several each year. They're also prone to getting caught in fishing nets, boats and other human aquatic devices.

Manatees may have an impact on the ecosystem when they repeatedly return to the same beds of sea grass and graze. Manatees most often feed on the edges of sea grass beds and they remember where these food sources are when they move from spot to spot. Although there is no documented proof, the constant "mowing" of these sea grasses may do them harm in the long run.

Manatees are often impacted by human destruction of their habitats as well as collisions with boats, getting trapped/caught in fishing lines/nets and human interaction that changes their breeding and feeding and swimming patterns.

Manatees are long-lived animals if they are allowed to be. One manatee in a Florida aquarium was born in the late 1940s and is over 60 years old. Manatees do not tolerate cold water or weather and confine themselves to warmer waters.

One was seen as far north as Cape Cod in Massachusetts, but they do not normally reside any further north than Virginia. They migrate back to the warm Florida and Gulf Coast state waters in the winter.