252 Department of Conservation of Louisiana 



dering the Gulf of Mexico. However, in certain sections 

 of the coastal area rice growing has been introduced. To 

 do this successfully, canals have been dug and by the aid 

 of high levees the irrigation waters raised above the marsh 

 floor. These levees have attracted many muskrats that 

 normally are "house" builders and, forsaking this habit, 

 they have dug their burrows, tunnels and dens in the banks 

 thus erected for them by man, as the following observations 

 show. 



Muskrats in Levee Banks 



While engaged in experimental work in blackbird con- 

 trol in southern Vermilion Parish, Louisiana, in March and 

 April, 1926, E. R. Kalmbach, biologist of the United States 

 Bureau of Biological Survey, had opportunity to take notes 

 on the habits of muskrats in the rice fields, and reported as 

 follows : 



"Learning that those now engaged in a study of the 

 Louisiana muskrat had seldom noted the presence of musk- 

 rat burrows in the hard banks of irrigation canals in the 

 rice belt and made observations that were at variance with 

 the statements of certain rice growers who (at least for- 

 merly) experienced considerable trouble in ridding the 

 levees of these burrowing rodents. 



"My notes were taken in the vicinity of Gueydan, where 

 my attention was called to the levee burrowing habits of 

 the muskrats and the measures that are taken to prevent 

 the undermining of canal banks. It is generally conceded 

 that the extent of this damage today is slight compared 

 with that which occurred in former years, but even under 

 present-day conditions a certain part of the work of canal 

 crews is in connection with the repair of muskrat excava- 

 tion. 



"The prolonged drought of 1924 and 1925, which had 

 increased the salinity of most of the inland waters of the 

 Gulf Coast area, resulted in some of the canals being drained 

 of all or most of their water. There had been no need to 

 refill them up to the time of my observations in March and 

 April, 1926. With only a few inches of water in the beds 



