38 Conservation Department 



III. Biological Studies of Polluted Areas in the Genesee 



River System 



By P. \V. Claassen, 



Professor of Biology^ Cornell University 



In connection with the stream survey of the Genesee river and 

 its tributaries, considerable attention was given to the study of 

 stream pollution. The object of the investigation was to deter- 

 mine the following': first, the different types of pollution which 

 enter the waters of the Genesee river and its tributaries; second, 

 the exact location of the source of each case of pollution ; third, a 

 study of the effect of the ])onution substances upon fish and upon 

 all other fresh water animals and plants commonly found associated 

 with fish life ; fourth, collecting and determining the plants and 

 animals Avhich occur in polluted waters with a view of establish- 

 ing a record of the particular types of organisms which occur in 

 waters polluted by different kinds of w^astes, in other words, 

 attempting to establish biological indicators which would be of 

 use in determining the condition of the water and its suitability 

 for fish life ; fifth, suggestions of remedial measures. 



Milk Pollution. — Milk wastes in the form of whey, skim milk, 

 washings, etc., constitute the commonest type of pollution in the 

 Genesee valley. Milk plants are particularly abundant in Alle- 

 gany county. The waste from these plants when introduced into 

 streams in sufficient quantity constitutes a serious case of pollu- 

 tion. A small amount of milk may serve to fertilize the water 

 and enrich the life of the stream without materially affecting fish 

 life, but in larger quantities milk wastes reduce the oxygen con- 

 tent of the water and become deleterious to fish life. Whey is 

 l)robably the most detrimental of any of the milk wastes and 

 should, under no consideration, be allowed to enter fish -inhabiting 

 waters. Aside from the question of fish life, milk Avastes usually 

 produce an unsightly stream and oftentimes create a public 

 nuisance and i)ossibly a menace to the health of man and beast, 

 in that such foul waters are es])ecially suited for breeding mos- 

 quitoes. Fui-thermoi-e, live stock will not drink Avater that has 

 become badly i)ol luted. 



The typical index organisms found in niilk-i)olluted water in- 

 clude the following: Xcai- llie cnti-ance of the milk wastes into 

 the streams, i)articularly in |)hices wliei-e tlici'e are I'ifles in the 

 water, occur al)un(lan1 gi-o\\1lis of sewjige fungus {Thiofhrix, 

 Ijpfofhrir, etc.). Within Ihcsc fungus growths usually are found 

 many ])i-otozoa (Ciliafes) of Ihc foul watei- types. Generally next 

 in abundance ai'e the snails, Physd, PUtiiorbis and Limnva, air 

 breathers whicli come to the surface of the water for air, and 



