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Nutria (Myocastor coypus) in Louisiana.pdf
  • John A Baroch
  • Mark S. Hafner
  • Tommy L. Brown, Cornell University
  • Jeff J Mach
  • Richard M. Poche
Abstract:  The nutria or coypu  (Myocastor coypus) is a rodent native to South America that has been introduced almost worldwide since the early 1900’s, originally with the intent of fur farming in many cases.
The nutria is a large (over 6 kg), semi-aquatic rodent with a voracious appetite and high reproductive potential.  Nutria became established in the Louisiana wetlands in the 1930’s.  The habitat proved to be ideal and populations exploded, reaching an estimated 20 million animals in less than 20 years.  Trapping of nutria for their pelts formed the backbone of the Louisiana trapping industry from the 1960’s until the early 1980’s when prices for furs on the world market and in Louisiana fell drastically.  Since then the annual trapping harvest, which was over one million animals per year for many years, has dwindled to 29,544 in the 2000-2001 season.   Since the virtual cessation of the annual harvest, nutria numbers have increased dramatically.  Reports of damage to wetland habitats emerged in the late 1980’s.  Numerous studies of the wetland environments of Louisiana since then have documented the deleterious effects nutria grazing is having on the habitat.   While nutria serve as an important prey item for the alligator, effects of nutria activity on other animals are primarily negative.  Their most important impact is habitat modification and in many cases, habitat destruction.  When impacts of intense nutria herbivory are added to the abiotic forces that are degrading the Louisiana coastal marshes the potential for lasting loss of wetland area is magnified.  This report reviews the general biology and natural history of nutria;  the chronology of nutria establishment in Louisiana and historic population fluctuations;  interaction of nutria with other animals in Louisiana, and impacts of nutria herbivory on the wetland plant communities.       
  • Invasive species,
  • Nutria,
  • Louisiana
Publication Date
Spring March 31, 2002
Citation Information
John A Baroch, Mark S. Hafner, Tommy L. Brown, Jeff J Mach, et al.. "Nutria (Myocastor coypus) in Louisiana.pdf" (2002)
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