INTRODUCTION 
The establishment of the nutria or coypu (Myocastor coypus ) in 
Louisiana has aroused interest in the United States, originally be- 
cause of the fur resource it provided and later because of its 
tendency to damage marsh vegetation and agricultural crops. Since 
the escape of individuals from confinement at Avery Island, Louisiana, 
in 1940, nutria increased greatly in number in the Louisiana coastal 
marshes. Populations soon developed in the area north and west of 
Vermilion Bay, on Marsh Island in the Bay, and at Lacassine Refuge 
(Fig. 1). During the middle of the 1950's, populations increased 
rapidly elsewhere along the coast of Louisiana. As a result of 
introduction and natural spread, nutria now occupy the coastal mar- 
shes from Galveston, Texas, to northern Florida; and colonies have 
developed at. many points inland, especially in eastern Texas. 
Concomitantly with the development of large nutria populations 
in the Vermilion Bay region, a trend toward loss of vegetation-- 
particularly the taller and coarser species of plants--became 
evident during the early part of the 1950's. Because of its abun- 
dance and food habits, the nutria became suspect for this loss of 
vegetation. 
Some marshland owners and managers feared that these vegetative 
losses would cause a decrease in the wildlife resource of the marsh. 
However, one of the goals of waterfowl management in the Gulf States 
