Nutria damage is evident to varying degrees in every area they are found.
Damage to Agriculture
In the United States, sugarcane and rice are the primary crops damaged by nutria, but they will also eat corn, milo, sugar and table beets, alfalfa, wheat, barely, oats, peanuts, and various melons.
Damage to Property
Nutria burrows, which can extend up to 150 feet long, cause extensive damage to stream banks, canals, irrigation structures, levees, and other property. Their burrows can damage flood control levees that protect low lying areas; weaken the foundations of reservoir dams, buildings, and roadways; and erode the banks of streams lakes, and ditches. Nutria girdle fruit, nut, and shade trees and ornamental shrubs, and they may dig up lawns and golf courses when feeding on the roots and shoots of sod grasses.
Health and Safety Concerns
Nutria are vectors for wildlife diseases including tuberculosis and septicemia, which are transmissible to people, pets, and livestock. Nutria feces and urine can contain parasites such as nematodes, blood flukes, tapeworms, and liver flukes that may contaminate drinking water supplies and swimming areas used by people.
Damage to Natural Resources
Nutria cause damage to marshes and other wetlands. Unlike native rodents, nutria consume not just the succulent leafy portions of marsh plants, but also the roots, rhizomes, and tubers, leading to complete destruction of the plant. In most cases, nutria damage to marsh vegetation and soils is so severe that the marsh is converted to open water.
Nutria have removed much of the vegetation in this section of Chesapeake Bay marsh. Two years after nutria removal, this same section of Chesapeake Bay marsh has become revegetated.