Biological Survey — Oswego Watershed 15 



to October, and it has been demonstrated that carp in these num- 

 bers can be taken with minimum interference of game fish. 



The dominance of carp in Oneida is evidently correlated with the 

 richness and abundance of certain food elements such as Crustacea, 

 mollusca and insect larvae which are the main food staples of the 

 carp in this lake. 



Other contributing factors are associated with the unusually 

 favorable physical features which obtain there, such as the exten- 

 sive shallows and the intersecting barge canal which provide agree- 

 able environmental conditions for this species. 



Although much useful information has been gained by the efforts 

 o± a single season, relief measures to be adequate, however, must 

 be organized for permanency. In this connection the economic 

 aspect is an important consideration. When more carp are mar- 

 keted than are yearly produced then we may hope to cope with the 

 carp problem in situations where game fishing is to be regarded as 

 paramount. 



Conditions of Pollution in the Oswego Watershed. — An 



appraisal of the waters from the standpoint of the oxygen supply 

 is shown graphically in the dissolved oxygen profile of the Seneca 

 and Oswego rivers (Fig. 1.) These are the recipients of the mis- 

 cellany of pollutions of all tributaries, both lakes and streams, in 

 the watershed. Gathering up as they do the waters of the entire 

 drainage basin they become rivers of considerable volume. The 

 profile, therefore, is impressive as showing despite this large 

 volume of water a successively lower and lower oxygen sag until 

 the final entry of the waters into Lake Ontario. Other profiles 

 of the tributary streams interpreting pollution conditions in local 

 areas appear in the report on this subject. 



In the biological discussion of the subject (page 138) a useful 

 tabulation of pollution conditions in the watershed provides data 

 ot importance to each community in which studies have been made. 

 The types of polluting substances which enter the river system are 

 discussed in their relation to fish life and to the organisms asso- 

 ciated with them in the capacity of food of fish either directly 

 or remotely. The mileage of stream noticeably affected by the 

 polluting wastes is estimated at about 108 miles, an approximation 

 based upon the condition of the stream as shown both by oxygen 

 depletion and the presence of biological indicators of pollution. 



In stressing the studies of pollution, three objectives stand forth. 

 The first of these is to give information of pollution conditions 

 in the watershed, to visualize, that is, graphically by profile or 

 otherwise the situation as a whole in the area covered by the sur- 

 vey. The second to focus attention upon the bad spots, the 

 conspicuous cases of stream defilement where the normal fauna 

 and flora are completely replaced by pollutional forms and by gas- 

 eous or other conditions inimical to fish life, and where under such 

 situations stocking the stream with fish is extravagant and waste- 

 ful. And third, to emphasize the responsibility of the individual 

 and the community. 



