What Does a Nutria Eat?

Nutria (Myocastor coypus) are large rodents that are semi-aquatic in nature. They are indigenous to South America and can be found in Argentina, Brazil, Bolivia, Chile, Paraguay and Uruguay. In the 1930s they were imported to the United States as part of the fur trade industry and were released either intentionally or accidentally into the wild. They can now be found in approximately 20 different states. Nutria are omnivores with a large appetite and the ability to eat many different types of plants.

  1. Plant Food Sources

    • Nutria have a varied diet and can feed on many different types of plant life. They live in semi-aquatic marsh lands and will feed on different types of marsh grasses and vegetation. Olney-three square, saltmarsh hay, bullwhip, cattail, duck-weed, alligator weed and smooth cordgrass are types of marsh vegetation nutria have been known to gorge on. Nutria will also eat lawn grass and crops in homes and fields near marshy areas. They often eat the base of plants causing damage and will dig for roots and rhizomes during the winter.

    Other Food Sources

    • Nutria feed almost entirely on plant life, but near a coastline they may feed on other organisms. They can feed on shellfish, including snails or mussels and other small aquatic life. It is not uncommon for these animals only to feed on plant life, but since some may eat meat, they are classified as an omnivore and not an herbivore.

    Eating Habits

    • The two time periods in which this species eats the most are just after sunset and just prior to sunrise. They can eat both on land and in the water and will eat 25 percent of their body weight per day, making them large consumers of plant life. Males are slightly larger than females, with the average weight being 12 pounds and an average of 4 pounds of plant matter being consumed daily. They can eat just about any type of plant matter and will eat whatever is easiest for them.

    Wetland Damage

    • Nutria have caused extensive damage to the wetlands in Louisiana because of their feeding. The Louisiana Department of Natural Resources conservatively estimated that 80,000 acres of wetlands have been damaged due to overgrazing by nutria. When the vegetation is removed from the surface of wetland areas, the soil becomes exposed to tidal waters and is quickly washed away. The plant root systems of these areas are also damaged, making it very difficult for vegetation to grow back. This problem occurs in most wetlands where nutria live, not just in Louisiana.