Nutria Feeding Activity and Its Effect on Marsh Vegetation in Southwestern Louisiana

A study of the effect of Nutria (Coypu) on marsh vegetation was made in southwestern Louisiana from 1954 to 1956 by means of plant transects, enclosures, and indices to Nutria abundance. Plant species studied included Saltmeadow cordgrass, Olney's three-square, Big cordgrass, Reed, and Sawgrass. Nutria had a pronounced effect, except for limited areas, only on Big cordgrass. It is concluded that Nutria did not have a major effect on the marsh vegetation as a whole, and did not create extensive bare areas. It is pointed out that the marsh habitat is dynamic and complex and many factors are undoubtedly involved in the changes that have occurred.