Bullock. — Problems in Bass Culture 133 



were drained as soon after July 15th as we failed to find 

 school.* present and the work could be begun and completed. 

 Three purposes were in view ; first to sweeten pond 

 bottoms by letting air permeate through them as long as 

 possible; second to have summer suns and winter freezes 

 destroy the undesired weed, Pennywort; and third, and most 

 important, to reduce the number of carnivorous insects. We 

 had too many giant water beetles, Dytiscus, giant water 

 bugs, Benacus, water mites, water scorpions, small diving 

 and whirligig beetles, etc. 



The results were satisfactory. The warm weather last 

 winter spared too m.uch of the Pennywort, but carnivorous 

 insects were very scarce this season while more daphnids 

 could be seen along the shores in the early months than in 

 all the previous five years combined. The final proof of 

 the advantage of very early drainage is shown in the output. 

 It was much larger this year, as compared with any other 

 in the history of the station. 



The food given to bass at this station had always been 

 chopped fresh mullet. It is a species rich in oil; the many 

 dead bass examined showed the stomach surrounded by a 

 mass of fatty tissue, and it was thought that perhaps the 

 food might, in part, account for the high mortality, besides 

 the cost of mullet seemed prohibitive. 



Grouper and other fish were offered the bass as a sub- 

 stitute, but were refused. Next strips of beef heart were 

 tried and were taken by the bass ciuite as greedily as had 

 been the mullet. They could be purchased for less than a 

 fourth the cost of mullet, at that time, and we became 

 optimistic. We knew that hearts were fed at many of the 

 Bureau's stations and that their mortality and costs as well 

 were low. 



Pig hearts were made our regular food, beginning July 

 1st, 1921. All seemed going well until spring. Then loss 

 of adults became so high that on May 25th, 1922 the order 

 for hearts was discontinued and a return made to mullet as 

 fish food. Not only was the loss, under a heart diet, ex- 

 tremely high, but the output per adult was probably the 

 lowest ever experienced here. 



It may at times be advisable to cut off the artificial food 

 altogether. In distributing our broodstock from the hold- 

 ing pond to the numerous spawning ponds, the past Febru- 

 ary, it was decided that the fish were too fat. All feeding 

 was discontinued for six weeks. The results were satisfac- 

 tory. 



Probably all pond stations are troubled with algae. We 

 have it too. Our scientific advisers tell us it is not to be 



