Coastal Loss Series, Part Two: Nutria – How an introduced species can affect a habitat


This is the second of a four part series focused on Coastal Loss and presented by the NOTG Conservation Committee.

We often talk about the damage that invasive, non-native plant species can do to our environment. Louisiana’s coastline has been affected detrimentally by a particular non-native mammal, the nutria, who does his damage by feasting on the roots and grasses that hold together Louisiana’s marshland.

Nutria were introduced to Louisiana from South America in the 1930s to bolster the fur industry. It wasn’t long before they escaped or were released. The habitat here suited them well, but they became an agricultural nuisance to rice and sugarcane farmers as early as the ‘40s and ‘50s. They were also blamed by the trapping industry for a decline in populations of the native muskrat. In the 1960s, the Louisiana Department of Wildlife and Fisheries led a cooperative effort to market nutria fur. By the late 1970s, the price per pelt was peaking. Nearly 2 million pelts per year were being harvested. Damage to crops declined, and muskrats began to recover. In the 1980s, demand for fur declined abruptly, mostly due to the anti-fur movement. The price per pelt shrank to near nothing so trappers lost their economic incentive, and the nutria rapidly became a nuisance again. This time it wasn’t so much the crops, but rather coastal marshes, that suffered.

Nutria are well-adapted for the semi-aquatic environment of south Louisiana. Their highly-placed eyes, ears, and nose stay above water when they swim, and the female’s teats are on her back allowing her young to float while nursing. Nutria breed prolifically, producing two litters per year, and young are born fully furred and ready to eat vegetation within hours of birth.

The population peaked in late 90’s and nutria were killing marshes through over grazing or “eat outs.” By early 2000, nutria were destroying 90,000-100,000 acres yearly. In 2002 the State began a monitoring and bounty program, Coastwide Nutria Control Program (CNCP), which today pays $5/per tail. 350,000 nutrias are removed from the coastal zone annually and coastal damage is down to 10,000 acres yearly thanks to the program.

Nutria Facts and Figures

SCIENTIFIC NAME: Myocastor coypus

TYPE: Mammals

DIET: Omnivores



SIZE: Head and body, 17 to 25 in; tail, 10 to 16 in

WEIGHT: 15 to 22 lbs