322 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



It may be advisable in some places to reduce tlie density in the ponds 

 below that of the open waters, as it is well known that the more brack- 

 ish waters are generally most favorable to the rapid multiplication of 

 diatoms and other minute vegetable forms valuable to the oyster-grower. 

 Experiment could be made to demonstrate approximately the best 

 density for the purpose, and where the water supply is under control 

 the pond could be maintained at nearly or quite the degree of salinity 

 required. The ordinary surface drainage into many natural salt ponds- 

 is sufficient to reduce the density below the level in the main waters, 

 and by merely regulating the inflow of sea water the grower will prob- 

 ably find that almost any degree of brackishnessmay be maintained at 

 will. Such ponds will be found to possess all the requirements for the 

 production of food in abundance, the density will be favorable, their 

 shallowness will cause them to warm early in the season, and thus 

 stimulate the growth of microscopic vegetation, and their immunity 

 from the influences of tides will prevent the carrying away of the food 

 which they produce. 



There are, of course, many places where the natural conditions for 

 the i)roduction of oyster food are all that could be desired, and there 

 pond culture would doubtless be unnecessary, but in other localities, 

 such as are mentioned at the beginning of this section, it seems to ofler 

 the most i^romising field for experiment. 



BREEDING OYSTERS IN PONDS. 



While in some of our most important planting regions there is rarely 

 any difficulty in obtaining seed oysters, there are places, otherwise 

 admirably adapted to the industry, in which the supply of seed is 

 extremely precarious. The most remarkable fluctuations in the set of 

 si^at take place, and often where there is one year an abundance the 

 following season may exhibit a dearth. In certain localities on Long 

 Island a set of spat rarely occurs, and the planters long ago abandoned 

 the attempt to raise seed and now procure it from some other region 

 more favored in that respect. In still other places, as over the larger 

 part of Chesapeake Bay, the seed oysters are obtained mainly from 

 the natural beds, but with the depletion of these there will be an 

 increasing difficulty in obtaining it, and before long it will no doubt be 

 necessary to derive it from some other source. There is an increasing 

 tendency in the region last mentioned to follow more closely the method 

 of sowing shells practiced in Connecticut; in some places the experi- 

 ment has met with great success so far as the procuring of a set is con- 

 cerned, but in other localities the results are too uncertain to permit it 

 to be followed with profit. 



Where a "strike" occurs each year with tolerable certainty this 

 method is without doubt the best available to our oystermeu, but where 

 the spat may fail to set for several years in succession, the expense of 

 putting down the shells without return will soon eat up the profits of 



