The environmental problem grew out of the ruthlessness of the nutria's eating habits. It treats the Mississippi Delta as its personal salad bar. It feeds by paddling around a heavily vegetated marsh and seeks out the tender roots of aquatic plants, chewing its way up to the leaves, which it ignores. Ninety percent of the plant floats away. Replanting has been tried on a limited basis, with little success.
Nutria follow behind, eating the tender shoots of the new plants.
Even when they aren't eating, nutria burrow into levees, causing them to collapse. They are strong swimmers. Adults grow to about the size of a small beaver, propelling themselves with webbed back feet and steering with their rope-like tail. Their vegetarian diet provides little fuel, so nutrias must eat constantly. When they aren't eating, they have one other major interest.