Lacassine Refuge and south of Pecan Island have been affected by 
nutria only around edges next to canals or bayous. A dense bul- 
rush stand is evidently not a favored nutria habitat in south- 
western Louisiana. 
Southern bulrush is not of great importance to muskrats in 
the brackish marsh (Lynch et al., 1957). Its seeds form an im- 
portant part of the diet of ducks in the region (Chamberlain, 1959). 
Cattail, existing as a minor vegetative type in southwestern 
Louisiana, is said to be a favorite food of nutria there (Dozier, 
1951) and in Washington (Guenther, 1950). Cattail existing as 
isolated plants on Transects A, C, and D were frequently utilized 
as food by nutria. Small stands of cattail were “clear-cut” in 
Texas (Swank and Petrides, 1954) and in Russia (Vereshchagin, 1941) 
and almost completely eliminated in Israel (Glazner, 1958), England 
(Laurie, 1946) and in Germany and Poland (cited by Ehrlich, 1957). 
The discussion of the effect of nutria on the plant species 
studied indicates that, with the exception of big cordgrass and 
cattail, nutria have not been a primary cause of the loss of 
emergent, marsh vegetation in southwestern Louisiana. On the con- 
trary, general observation has led us to believe that dense marsh 
vegetation does not provide optimum conditions for nutria. Nutria 
seem co prefer areas where vegetation is open or where it is inter- 
spersed with openings and made available by canals, pirogue ditches, 
and natural waterways. Much of their movement is along trails 
tInade by them or other animals, and trails made by man or marsh 
ey 
