74 American Fisheries Society 



Ma. Bower, of Michigan: I agree with the President that this 

 surpasses any record of which I have any knowledge. We are carry- 

 ing on similar experiments, but have never begun to equal it. I think 

 it is due very largely to the high temperature of the water and the 

 production of an immense amount of natural food. In our latitude 

 we could hardly have the same conditions and our ponds, if they ever 

 get as warm would not remain so for many days in the year. It 

 shows what might be done and that we might very profitably engage 

 in such culture, but whether it could be made more profitable than 

 Hand culture I do not know. 



Mr. Lydell, of Wisconsin: We have a pond similar to the one 

 Prof. Dyche has described, and for the last two years we have been 

 dumping into it almost everything with the idea of rearing our own 

 stock fish instead of collecting them in other waters. So far we have 

 been very successful, but nothing to compare with Prof. Dyche's ex- 

 periment. This pond is about 72 degrees, at the warmest, so that we 

 could not get the same growth in the same length of time as he 

 would get in a warmer pond. We are hoping to build a larger pond 

 with a view of raising our breeding stock instead of collecting it. 



Dr. Geo. W. Field, of Massachusetts: May I call particular atten- 

 tion to the fact that this is one of the best and one of the first in- 

 stances, perhaps, of definite information as to the quantity of fish 

 that can be raised in a given amount of water. Also there is the 

 question of handling this pond on the principle of the aquarium, with 

 the specific data of how much food a certain quantity of fish require. 

 The application of this is very important. As the country becomes 

 more settled, it is absolutely necessary to furnish the people with pure 

 drinking water. If, on the one hand, carnivorous fish are allowed to 

 grow in reservations of drinking water, judging from observations 

 we have made, you will get a small number of large fish, and the 

 algae which cause the poisonous odors and taste in drinking water 

 will multiply unduly. On the other hand, if the right proportion of 

 carp fish are kept you will have the best conditions to secure the 

 best quality of water. We need specific data on ponds, and Prof. 

 Dyche's work will help very much toward the solution of the problem. 



Mr. Titcomb, of Vermont: In our part of the country it would be 

 impossible to do anything of this sort. The colder the water, the 

 less the number of fish. A great many deductions can be drawn from 

 these data and I want to inquire of Prof. Dyche whether, if he were 

 to conduct the experiment again, he would put in as many fish as 

 he did in this case? I believe he acknowledges he would not put the 

 catfish in. 



Prof. Dyche: I am in doubt. I would not leave out the hickory 

 shad or the goldfish, for I prefer these for food fish. I am not sure 

 about the carp, they grow pretty large, and the young carp grow faster 

 than the goldfish. I would leave out the carp and the channel catfish, 

 but nothing else. I do not say that you would have to have goldfish 

 and hickory shad, but there should be fish enough of some kind to 

 consume a large amount of waste and convert it into food for the 

 yoimg bass, blue-gills and crappies. The blue-gill is one of the best 

 fish we have for food for the bass. We are raising tens of thousands 

 of blue-gills and goldfish. The blue-gill spawns aljout a month later 

 than the bass and on examining young bass in the fall we find they 

 have been feeding on the blue-gills. If they do not have these or some 

 other fish to feed on they will eat each other. 



Mr. Titcomb: You have considerable algae? 



Prof. Dyche: Yes. At certain times in the spring the spirogyra 

 is abundant. The goldfish feed on it. Duckweed comes in immense 

 quantities, and the goldfish feed extensively upon it. We have 20,000 



