Establishment and Food Habits of the Nutria in Texas

Abstract

The nutria (Myocastor coypu) has been an object of considerable interest and discussion during the past few years. Ashbrook (1948) discussed importations from their native rivers, estuaries, and marshes of South America to fur farms in Germany, Switzerland, France, Canada, Russia, and the United States. In this discussion Ashbrook also related how many of these animals escaped or were released into the wild due to financial failure of the fur farmers. Atwood (1950) reported on the life history of this exotic in the coastal areas of Louisiana. Those occurring in Texas are descendents of animals imported by E. A. McIlhenny to Avery Island, Iberia Parish, Louisiana in 1937. Dallas fur buyers have reported that as early as 1946 a few nutrias were trapped along the coast near Port Arthur, in southeastern Texas, but apparently there was no appreciable natural spread of this species inland. In April of 1946, Mr. A. C. Lively, reportedly with the intention of growing nutrias for their fur, obtained 20 females and four males from Avery Island and released them in a 300-400 acre marsh near Slocum, Anderson County, 160 miles inland from Port Arthur. About the same time Mr. C. N. Campbell. a relative of Mr. Lively, released three animals into a small five-acre pond near Grapeland in Houston County (Petrides 1950). The outcome of the introductions into Mr. Campbell's pond seemed to be the impetus behind wholesale introductions in 1949 and 1950. According to Mr. Campbell and his neighbors, the pond into which the nutria were released was practically filled with vegetation in 1948 when they were first introduced. By the summer of 1949 it became apparent to the importer that there was much less vegetation in his pond, a condition which he attributed to the activities of the nutria. Since Texas pond owners frequently encounter difficulty in controlling aquatic and semi-aquatic vegetation in impoundments, Mr. Campbell began selling nutrias on the strength of their apparent ability to remove undesirable water weeds. The supply of nutrias from Mtr. Campbell's small pond was