THE OYSTER-GROUNDS OF THE WEST FLORIDA COAST: THEIR EXTENT, 

 CONDITION, AND PECULIARITIES. 



BY FRANKLIN SWIFT. U. S. NAVY, 

 ( 'oinmanding United States Fish Commission Steamer Fish 



The oyster-grounds of the west coast of Florida extend the whole length of the 

 coast. Oysters are found growing in great abundance in the waters between the 

 mainland and keys, and are particularly noticeable clinging to the roots of the 

 mangroves which fringe the mainland and keys along the southern coast. These 

 oysters of the extreme southern waters of Florida are mostly of the raccoon type and 

 are not very palatable, being "coppery" and of poor quality. 



The oyster regions of the central and northern part of the coast are found in the 

 many inclosed bodies of water, and are located in the vicinity of the mouths of rivers 

 in waters where the density is affected by the fresh water of such streams. The 

 question of density is of prime importance in connection with oyster growth, and 

 edible oysters can only grow where the salt water is influenced by that of less density. 

 If the normal sea water is taken at 1.026, then 1.016 represents the most favorable, 

 density for oyster life. However, the densities in which oysters seem to thrive cover 

 a great range, and in nearly all beds oysters are subjected to the extreme ranges 

 between the different stages of the tide. In freshets oyster-beds are sometimes 

 destroyed, owing to the long-continued prevalence of fresh water. 



The oysters of the west coast of Florida are all found in very shoal water com- 

 pared to those found in the Central and Northern States, and a glance at the chart 

 will show the comparative shallowness of all the inclosed bodies of water along the 

 west coast. Marketable oysters are taken in water from 10 feet to 1 foot in depth, and 

 in less than 1 foot and above low-water mark are found the raccoon oysters. Large beds 

 of the latter type lie exposed at low water and thrive, even in their exposure to the hot 

 sun or cold air, during the low ranges of the tide. The shells of these oysters are long 

 abd pointed quite sharply, and the oysters are more flat than those of the marketable 

 type. These oysters, culled and transplanted, often do well on cultivated grounds. 



The bottoms of the coast waters which contain oysters are almost invariably very 

 soft mud, and it appears remarkable how the solid beds are ever formed on such yield- 

 ing material. The mud is often of the nature of ooze, and a pole may be thrust down 

 many feet before finding any resisting strata. An examination with a steel pointed 

 probe usually shows the following strata on the beds: The crust of the bed, composed 

 of shells to a depth of 2 or 3 feet; a layer of soft sand, extending down about 5 feet, 

 and then hard sand or hard mud. The beds are almost entirely long and narrow m 

 extent, and rise precipitately from the muddy bottom, forming reefs dangerous to 

 navigation, as no warning of their presence is given by the soundings. On these 

 reefs there is usually 2 or 3 feet of water at low water. In some localities the oysters 

 are scattered over the bottom, forming beds like the northern beds, but it may be said 

 generally that the oysters of the natural beds grow on the densely packed reefs before 

 mentioned. 



