156 American Fisheries Society 



traversing ten feet of gravel. Many years ago I saw an instance 

 where fry from a leaky pond travelled two hundred feet through 

 the earth, emerging on a meadow; hence their ability to get 

 out need not be questioned. 



When I am asked if the gravel system is as compact as the 

 other I usually suggest to the inquirer that he substitute "con- 

 gested" for compact, for that is the way I view it. Last year I 

 took out a group of four sixteen inch by sixteen feet troughs 

 and in its place erected a system for sixty gasoline cans. I put 

 one hundred and eighty quarts of humpback eggs in these cans in 

 varying quantities and sizes of gravel for experimental purposes. 

 Some of them were purposely overloaded and one hundred and 

 twenty quarts would have been enough. Now one hundred and 

 twenty quarts would have been a good load for the troughs I 

 took out, but it must not be overlooked that the trough and basket 

 method has only area, while the other has area multiplied by the 

 depth of gravel.- Anyway, compactness is no consideration when 

 better results are obtained, and the same thing applies to the 

 quantity of water used, which is twice that of the old way. 



Another question I have been asked is, "Is the proportion of 

 fry turned out as great as from the troughs?" Now, while I 

 have never counted the number of fry emerging from a container, 

 I have seen the contents of perhaps fifty whitefish jars hatch 

 and the fry leave in plain view, and when I say that the proportion 

 is as great or greater I know whereof I speak, and I also add that 

 I consider that gravel hatched fry have ten times the chance of 

 survival that trough fry have. One drawback is the difficulty of 

 finding suitable water and the use of gravel is cumbersome and 

 slow, but it is altogether likely that some other burying medium, 

 which must allow for expansion and the passage of water, will 

 be found to take its place. 



Its principal recommendations are, low cost of installation and 

 operation, but all the arguments for and against it pale into insig- 

 nificance in the light of its chief recommendation, which is, the 

 production of strong wild fry. 



