River Rat (Nutria)

December 27, 2012 by  

River Rat (Nutria), There are two commonly used names in the English language for Myocastor coypus. The name “nutria” (or local derivatives such as “nutria- or nutra- rat”) is generally used in North America and Asia; however, in Spanish-speaking countries, the word “nutria” refers to the otter. To avoid this ambiguity, the name “coypu” (derived from the Mapudungun language) is used in Latin America and Europe. In France, the coypu is known as a ragondin. In Dutch it is known as beverrat (beaver rat). In Italy, instead, the popular name is, as in North America and Asia, “nutria”, but it is also called castorino (“little beaver”), by which its fur is known in Italy.

Coypus live in burrows alongside stretches of water. They feed on river plants, and waste close to 90% of the plant material while feeding on the stems.

The coypu (from the Mapudungun, koypu), and nutria, is a large, herbivorous, semiaquatic rodent and the only member of the family Myocastoridae. Originally native to subtropical and temperate South America, it has since been introduced to North America, Europe, Asia, and Africa, primarily by fur ranchers. Although it is still valued for its fur in some regions, its destructive feeding and burrowing behaviors make this invasive species a pest throughout most of its range.
Nutria can live up to six years in captivity, but it is uncommon for individuals to live past three years old; according to one study, 80% of nutria die within the first year, and less than 15% of a wild population is over three years old. Male nutria reach sexual maturity as early as 4 months, and females as early as 3 months; however both can have a prolonged adolescence, up to the age of 9 months. Once a female is pregnant gestation lasts 130 days and she may give birth to as few as one offspring or as many as thirteen. Baby nutria are born fully furred and with open eyes; they can eat vegetation with their parents within hours of birth. A female nutria can become impregnated again the day after she gives birth to her young. If timed properly, a female can become pregnant three times within a year. Newborn nutria nurse for seven to eight weeks, after which they leave their mother.

Beside breeding quickly, each nutria consumes large amounts of vegetation. An individual consumes about 25% of its body weight daily, and feeds year-round. Being one of the world’s larger extant rodents, a mature, healthy nutria averages in weight at 5.4 kg (12 lb), but they can reach as much as 10 kg (22 lb). They eat the base of the above-ground stems of plants and often will dig through the organic soil for roots and rhizomes to eat. Their creation of “eat-outs”, areas where a majority of the above- and below-ground biomass has been removed, produces patches in the environment, which in turn disrupts the habitat for other animals and humans dependent on marshes.

Nutria are found most commonly in freshwater marshes but also inhabit brackish marshes and rarely salt marshes.

Report to Team

Please feel free to send if you have any questions regarding this post , you can contact on

Disclaimer: The views expressed on this site are that of the authors and not necessarily that of U.S.S.POST.


Comments are closed.