Lydell. — Fresh-Water Mussels as Fish Food 27 



Mr. G. C. Leach, of the U. S. Bureau of Fisheries. I believe the clam 

 meal is a very good fish food. I have ordered fine clam meal and the whole 

 clams with the intention of having five or six of our superintendents try 

 them out in the way Mr. Lydell has described. We have used it in Washing- 

 ton, under ideal conditions, with good success, feeding nothing else but clam 

 meal, mixed with water into a thick mush. We fed salmon, brook, rainbow 

 and steel-head trout, whitefish and perch. 



When the meal was dropped on the water some fish were quite wily, but 

 later, when it had settled to the bottom, they sucked it up. At the stations 

 where bass and other such fishes had been fed on beef heart they did not 

 take readily to the dried clam, but I believe that they could have been 

 trained to take it. We have not had a full report from the stations that 

 have used the meal, so I cannot say as to the results, but in Washington we 

 found it satisfactory. What results did you have, Mr. Seagle? 



Mr. Geo. A. Seagle, Wytheville, Va.: After feeding the young trout on 

 beef heart and liver they did not take to the clam meal readily, but I believe 

 that if we feed them on the meal first and nothing else they will take it 

 readily enough. 



Mr. John P. Woods, St. Louis, Mo.: I wish to give the benefit of some 

 experience I had during the years 1914 to 1918. When seining our ponds in 

 the summer time we took large numbers of crayfish. These were run through 

 a grinder with stale bread and substituted for other fish food. When this- 

 could be had there was a great demand for the crayfish substitute. 



A Member: The grinder we use is the same as for grinding beef hearts. 

 By using the fine plates and mixing with corn meal or low grade flour or 

 shorts we get any desired length or thickness we desire. But I think that 

 probably the greatest success with the clam meal, as Mr. Lydell suggests, 

 is as food for Daphnia, by scattering it around the edges of the pond where 

 it serves as food for the small organisms. 



Mr. Leach: We use crayfish a good deal at the Ocean Station, grinding 

 it and mixing with low grade flour or shorts. It makes a very nice food. 



Prof. E. E. Prince, Commissioner of Fisheries of Canada: I believe the 

 fish get rather tired of heart or liver when fed continuously, though it 

 appears, as Mr. Seagle says, that they don't take readily to new food when 

 offered. But experiments in fishing show, in the east at any rate, that fish 

 can be caught more readily by a change of food. For instance, if the fisher- 

 men have been using soft-shell clams and then change to mussels they will do 

 better. In one locality I know sea-anemones were used as a change and the 

 boats using them caught more fish than the other boats, as though the 

 novelty attracted the fish. 



But there is one thing about Mr. Lydell's clam meal which I think note- 

 worthy. It is a diet that embodies a variety of foods. The mussels contain 

 liver, muscle tissue, connective tissue, etc., and I think such a mixed diet 

 has much to do with the success of this food and the healthy character and 

 growth of the fish. 



