24 OYSTEE CULTURE EXPERIMENTS IN LOUISIANA. 



These recently-hatched borers probably feed upon the very minute 

 and newly-attached spat, though of this we have no certain knowl- 

 edge. Growth is rapid, as is shown by the experiments with boxes. 

 The mesh employed in these was one-fourth inch square, and the 

 largest borer that could be pushed through measured seven-sixteenths 

 of an inch in length. In closed boxes planted June 28 there were 

 borers three-fourths to 1^ inches long on September 1, an increase of 

 from 75 to 190 per cent in length and of from 200 to 450 per cent in 

 bulk within a period of about two months. 



The difficulties in fighting a small and insidious enemy such as 

 this are very considerable. It is wholly impracticable to inclose the 

 beds, as is done to prevent the inroads of drumfish and similar 

 enemies, the little snails being able to travel through the finest prac- 

 ticable mesh, and the only recourse is to wage unceasing warfare by 

 destroying all borers and egg cases found. To tong or dredge the 

 oysters especially for this purpose is commercially impracticable 

 under the market conditions obtaining in Louisiana, and the obvious 

 course for the oyster culturist in the more salt waters in which the 

 borer abounds is to eschew all effort at planting shells and confine 

 his activities to planting seed oysters at least 1^ inches and preferably 

 not less than 2 inches long. If he does this the presence of this 

 enemy may even prove a boon in preventing the excessive attachment 

 of spat to the older oysters, an occurrence which in some places on 

 our coasts renders it impossible to grow oysters fit for market. 



As to the rate of growth of oysters in the earlier stages at Bay- 

 Tambour little can be said for reasons which are apparent. The 

 growth of the seed oysters planted at the beginning of the experi- 

 ment was very satisfactory. In April, 1906, measurements of the 

 length of a number of these averaged 2.G inches. In June, 1907, the 

 average length was a little less than 4 inches, and in May, 1908, it 

 was about 5 inches. In less than two years, therefore, these oysters 

 doubled in length, and despite the fact that they were not culled, the 

 clusters automatically broke apart to some extent, owing to the dis- 

 integration of the shells to which they were attached, and there was 

 a corresponding improvement in shape. The growth here was about 

 the same as at Bayou St. Denis, and indicates that however unsuit- 

 able this part of the bay may be for spat culture, owing to the rea- 

 sons before set forth, there is an excellent opportunity for the estab- 

 lishment of an important and profitable industry in growing oysters 

 from seed. 



The results attained by the work at Bay Tambour are applicable 

 to all of that half of Barataria Bay lying nearer the gulf, our investi- 

 gations having shown the conditions to be essentially similar through- 

 out that region. During the last year or two of the experiments a 



