210 American Fisheries Society 



transport from (Bemidji to the St. Paul hatchery where the spring water 

 supply runs at 50°, and get the good results obtained in transporting from 

 Whitefis'h Lake, which is farther south and where the temperature variation 

 is not great as compared with St. Paul. 



Mr. Titcx>mb: This matter of temperature is a very interesting 

 subject. We gathered a lot of yellow perch eggs in one of our northern 

 lakes, and took them to a hatchery on Lake Erie which is furnished 

 with water from the municipal supply, obtained from the deep waters 

 of the lake. The water is all right for herring and whitefish but in the 

 spring of the year it is very cold, and our attempt to hatch yellow perch 

 in it was a failure. An attempt to hatch pike perch would be a failure 

 too, because the water does not warm up to the temperature that the 

 eggs require. 



It seems to be easier to carry eggs from a given temperature to a 

 slightly higher temperature than to carry them to a temperature in a 

 hatchery which is lower than the normal spawning temperature. For 

 example, I think it would be very difficult to take white perch eggs from 

 the Susquehanna River and hatch them in a New England hatchery, even 

 if it was supplied with water corresponding to the same conditions. 

 My impression is that the Bureau of Fisheries has transported quan- 

 tities of white perch fry from the Susquehanna River to northern waters 

 for the purpose of stocking northern ponds. But the waters of the 

 Susquehanna River being warmer than the northern waters at that season 

 of the year, the fry when planted in the colder northern waters could 

 not survive the sudden change in temperature. 



Mr. C. O. Hayford, Hackettstown, N. J.: During the past three 

 years. Professor Foster, of Lafayette College, has directed a biological 

 survey of about 2,000 miles of spring runs and trout streams, and it has 

 been found that there is an enormous difference between the fish in 

 these streams both in quantity and in size. You may have two streams 

 coming down a mountain under almost exactly the same conditions not 

 over a mile apart and one will be teeming with food while the other 

 has practically none. Some streams contain the most minute organisms ; 

 others contain organisms of the larger types. After three years' ex- 

 perience we find best results are obtained by planting fish according to 

 size and quantity of insect food, starting with No. 1 in spring runs and 

 headwaters, and using No. 2 and No. 3 as the streams grow larger. 

 The most interesting thing to us was the vast difference in size and 

 quantity of the various kinds of insects. We are trying, with Dr. 

 Embody's assistance, to work out a system of stocking according to the 

 amount of food per mile, for the different sizes of fish. 



Mr. Titcomb: That is what I would call, in common phraseology, 

 "great stuff." The work which Mr. Hayford has outlined as being done 

 in New Jersey is certainly ahead of that done in any other state. I 

 want to get to the point where all planting of fish will be done under 

 the supervision of somebody who knows something about it. If we 

 can get a survey of the waters similar to that which is made in New 



