The Gulf of Mexico 263 



drumfish is often destructive in some localities. The 

 only certain protection against it is a stockade of pickets 

 built about the beds, and such fences are often con- 

 structed. It is not, however, a general practice on the 

 oyster fields, and in most places there is little danger from 

 this oyster destroyer. 



If it should ever be possible to cultivate oysters in 

 Chandeleur Sound, steam vessels with large dredges 

 might be employed, as in Long Island Sound. There is 

 immense advantage in being able to gather large cargoes 

 rapidly, and in all kinds of weather. One of the disad- 

 vantages of the shallow waters in which oysters are now 

 cultivated is that dredges can seldom be used, and the 

 fishing must be done only with tongs. 



Now and then though at intervals of several years 

 the Gulf coast is visited by appalling hurricanes, that 

 shift the shallow bottoms and destroy great numbers of 

 oyster beds. 



The most serious menace to the industry in Louisiana 

 is the flooding of the fields with fresh water from crev- 

 asses in the Mississippi River. By consulting a map, it 

 will be seen by the courses of the waterways, that any 

 great break in the Mississippi levees below the mouth of 

 the Red River, may threaten the oyster territory either 

 on the east or west. The great Nita crevasse of 1890, 

 still often referred to by the oystermen, poured its flood 

 southward through Blind River, Lake Maurepas, Lake 

 Pontchartrain, and Lake Borgne, and freshened the 

 waters of St. Bernard Parish for so long a period that 

 oysters were nearly exterminated over an immense area. 

 The waters remained fresh for weeks, and the flood de- 

 posited a large quantity of sediment. Other great 

 crevasses have occurred, and some Qf them it has never 



