PROGRESS IN BIOLOGICAL INQUIRIES, 1929 1087 



LIMNOLOGICAL STUDIES 



In the years 1927 and 1928 the State of Ohio Division of Fish 

 and Game carried on a limnological investi<^ation of the western end 

 of Lake Erie in connection with studies on tlie distribution of larval 

 and postlarval fish. It was arranged with the Ohio organization 

 to have Dr. StiUman Wright take charge of the limnological work 

 for the year 1929. A hiboratory was established at Put in Bay, 

 Ohio, early in May, with two scientists in residence. During the 

 period from June 15 to September 15, the full staff of six investi- 

 gators was present, and the survey was continued until November 1 

 with a reduced staff. 



The area covered is that west of a line drawn from Point Pelee 

 to Cedar Point. The entire area is shallow and receives the waters 

 from three large rivers which carry the industrial wastes from 

 the cities of Toledo, Monroe, and Detroit. The purpose of the in- 

 vestigation was to make a general survey of the physical, chemical, 

 and biological conditions with particular reference to pollution and 

 its effect on the fish population. Chemical studies included analy- 

 sis for dissolved oxygen, free and fixed carbon dioxide, and hydro- 

 gen-ion concentration. Qualitative and quantitative studies of both 

 phytoplankton and zooplankton were made to. determine the vertical, 

 horizontal, and seasonal distribution of the various planktonts. Ob- 

 servations were also made of the distribution of pathogenic and 

 natural lake bacteria and of bottom organisms. A party working 

 independently studied the distribution of larval and postlarval fish 

 in the same area. The data are being prepared for publication. 



COOPERATIVE SURVEY OF LAKE ERIE 



The cooperative survey of Lake Erie, begun in 1928, was con- 

 tinued in the season of 1929. To the original institutions cooperat- 

 ing with the Bureau of Fisheries, which included the New York 

 State Conservation Department, Ontario Department of Game and 

 Fisheries, Health Department of the city of Buffalo, and the Buf- 

 falo Society of Natural Sciences, was added this year the Ohio De- 

 partment of Fish and Game and the United States Coast and Geo- 

 detic Survey. From these institutions a staff of 10 investigators 

 was recruited, many of whom spent much of the time actually in 

 the field aboard the United States Fisheries steamer Shearwater^ 

 which was assigned to the undertaking. 



During the winter period, extensive improvements and alterations 

 were made aboard the Shearwater^ including the installation of a 

 laboratory aboard, living quarters for five investigators, and various 

 mechanical improvements. 



The area of the survey was extended to cover the entire lake, with 

 the exception of a portion of the western end, which was subjected to 

 intensive investigation by the cooperative investigators of the State 

 of Ohio and the Bureau of Fisheries, as previously mentioned. 

 Actual field studies were pursued from May 15 to September 20 

 and consisted of four extended cruises from Buffalo to Put in Bay, 

 requiring usually about 15 daj^s, and numerous shorter cruises in other 

 sections of the lake for intensive investigations of the hydrography 



