ponds could be arranged, with an opening into the main pond, and we 

 could then raise our bass to the fingerling stage without cannibalism. 



Mr. C. O. Hayford, Hackettstown, N. J. : Dr. Embody deserves great 

 credit in this matter. Under his direction we polluted with milk some 

 trout ponds, measuring 5 ft. by 30 ft., and secured mosquito larvae in such 

 abundance that they could be dipped out by the solid quart. Our method 

 of collection is to use a net with a large bag, the bottom of which is 

 closed by a draw string. This is swept through the ponds, then lowered 

 into a pail half full of water, the draw string unfastened, and the con- 

 tents washed into the pail. A two-inch tea strainer is used in taking 

 them from the pail and throwing them to the bass. Both trout and bass 

 take them very readily. One hundred and eighteen were taken from the 

 stomach of a bass measuring 1% inches. The young fish follow the larvae 

 through the pond, and unless they can get to such shallow water that the 

 young bass cannot enter, every one will be taken. 



Another plan would be to construct your food-producing ponds so they 

 can be drained into the pond containing the young fish as soon as larvae 

 are developed. This does away with hand feeding. By covering a pond 

 with cheesecloth to prevent the adult mosqiiitoes from laying more eggs, 

 we can control the size of the larvae. If for any reason the larvae become 

 so numerous that they pupate before they can be removed, a little oil 

 poured on the water will kill them all, thus preventing an excess of adult 

 mosquitoes. 



I think the problem of raising mosquito larvae can be worked out for 

 each locality, and I believe that Dr. Embody has opened up a wonderful 

 field for us all to tackle. 



Mr. Titcomb : What was the size of the little bass when they took the 

 mosquito larvae? 



Mr. Hayford : They were about an inch to an inch and a half long, 

 and three weeks to a month old. We have plenty of microorganisms in 

 our waters and the bass feed upon them for about three weeks. By that 

 time the supply is running low, and mosquito larvae are fed. In one pond 

 where we fed the larvae we have about 12.000 young bass. Along one side 

 of the pond runs a concrete wall from which we feed. After feeding for 

 about two weeks, the young bass flock to the wall when the feeder appears 

 and follow him the length of the entire pond, feeding on the larvae with 

 the same eagerness that trout display in feeding. 



Mr. Leach : Do you think you can feed the mosquito larvae and 

 eliminate the daphnia, that is, let them take the place of the daphnia in 

 feeding the young bass? 



Mr. Hayford : I think after the bass are two weeks old they will 

 take the mosquito larvae. During the first three weeks we have plenty 

 of microcrustaceans for them to feed upon, and it is only when this supply 

 becomes exhausted that the larvae are necessary. 



Mr. Leach : A large number of our stations do not produce daphnia 

 and we have to depend on something else up to the feeding of artificial 

 food stage. If the mosquito larvae can be produced in large numbers, and 

 the rate of growth will not be too great they can be fed to the bass up 

 to the time they take the larger insect life. 



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