American /'ishrfirs Society 77 



Bureau. We could cuiploy uiany mnw nicu on all these subjects, ucit 

 ()ul\' of t'lsh diseases but others which are co-ordiuate. 



At this tiuie the Bureau is Iiaviug uiade analyses of the water supplies 

 of all of its hatcheries. Today no one can tell by an analysis of the 

 water whether it is suitable for supplying a fish-cultural station. Wc 

 are not even sure that we shall be able to establish a basis of analysis 

 whereby it may be definitely known that the waters will be suitable for 

 iisli culture. We know that many hatcheries have been started where 

 the water supply at the time was inhabited by fish. The natural infer- 

 ence, therefore, was that the water would be suitable for fish-cultural 

 purposes. But it often appears that such is not the case when the fish 

 are crowded together under artificial conditions. So far as known, 

 none of these diseases which the lish cullurist encounters is the cause of 

 much, if any, mortality among the fish in their natural habitat. 



At one station where for twenty years before a hatchery was estab- 

 lished the water supply was used for the maintenance of a series of trout 

 |)onds for the pleasure of a few sportsmen, the same w'ater supply to- 

 day will hatch one or two millions of trout, but at the time of sac 

 alisorption practically 80 per cent, of them die. Restock that hatchery 

 from another station with sac absorbed fry and it is possible to rear 

 any reasonable number of them to fingerlings. 



At another station the water contains a superabundance of air, and 

 this superaeration seems to be as dangerous as the lack of it. The old- 

 time fish-cultural writers who always required that you must locate a 

 hatchery away from the source of a spring and give the water a chance 

 to get into a normal condition, possibly did not realize that ihey were 

 taking precautions against superaeration as well as deaeration, the one 

 being as important as the other. 



The Bureau is making many observations along other lines. The 

 question of fish diseases must be investigated thoroughly, and after we 

 discover what the disease is there is the great difficulty of combating it. 

 In some instances the best way is to give up attempting to propagate 

 fish where the water supply seems to develop a disease like that produced 

 by the Bacterium tnittce, for instance. 



This emphasizes the necessity of so locating hatcheries that they may 

 he lirst operated as field stations. If you want to locate a trout liatchery 

 and you see trout in a stream, don't take it for granted that everything 

 is all right. Set up one or two troughs in a tent or shanty at an expense 

 of $100 or $200; put one man at work liatching the eggs; raise ihc fry 

 to fingerlings, carry them on througii inr a year — if any doniit arists 

 make it two years — and crowd them as much as you would at any lis!i 

 cultural station. In this way mistakes will be avoided and much monc} 

 saved for the purchase of sites and the construction of buildings and 

 ponds where the conditions are known to be right. (Applause.) 



Presujknt: Any further remarks on this subject? 



I dislike to take so nnich time of the Society, but really I think I 

 ought to explain my attitude on this c|uestion of the investigation of 

 fisii tliseases. 1 tlo not lind fault with anybody; 1 am not Iiere to con 



