would have been carried. The principal organisms present on the polluted 

 bottom were oligochaete worms. 



This brief preliminary survey brought out clearly that the lake was 

 heavily polluted near the large cities, and that the intensity of pollution 

 diminished rapidly with increased distance from the sources. Aside from the 

 reduction of space available to spawning fishes, pollution appeared not to 

 be sufficiently intense or widespread to constitute a serious menace to fish 

 life in the lake. 



Season of 1927 



In 1927 active direction of field work was taken over by Mr. E. L. 

 Wickliff. However, Dr. R. C. Osburn retained close connection with the 

 investigation in an advisory capacity. A field station was established 

 at Sandusky, Ohio, and work was carried out in the autumn and winter of 1927. 

 In addition to Mr. tfickliff, the scientific staff consisted of W. M. Tidd, 

 biologist, and M. K. Young, chemist, both of Ohio State University. During 

 this season attention was given principally to the fishes themselves, rather 

 than to environmental factors. Study was made of the food and parasites of 

 several species taken in Sandusky Bay and in the lake proper. Data on 

 length and weight, and scales from a considerable number of fish were taken. 

 These results will be presented in a separate report. Some environmental 

 studies were made, but principally in areas outside of Western Lake Erie. 

 For that reason the results will not be given here. 



Season of 1928 



In 1928 the base of operations was shifted again to ^ut-in-Bay, and a 

 laboratory was established in the hatchery maintained by the State of Ohio. 

 The personnel of the scientific staff was the same as in the preceding year. 

 In this season, for the first time, parallel studies of the fishes and their 

 environment were made. The principal immediate objective was to correlate 

 the distribution and abundance of the larval, post-larval, and adult stages 

 of the fishes with such environmental factors as temperature, currents, dis- 

 solved gases, plankton, and bottom organisms. Of necessity the limnological 

 observations were made subordinate to those on the fishes. 



The motor boat Investigator was outfitted especially for use of the 

 scientific staff. Work was concentrated in the area west of Point Pelee, 

 although some observations were made in the central basin of the lake. A 

 large number of stations were established and these were visited at fairly 

 regular intervals during the season, in order to determine seasonal changes 

 as far as possible. 



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