SURFACE CURRENTS OF LAKE MICHIGAN, 

 1931 AND 1932 



by 



John Van Oosten 



Fishery Research Biologist 



Bureau of Commercial Fisheries 



U. S. Fish and Wildlife Service 



Ann Arbor, Michigan 



ABSTRACT 



Seven hundred forty-five bottles containing post cards for recording of 

 information were released at stations in Lake Michigan; 283 were released June 17 

 to August 17, 1931, south of aline from Frankfort, Michigan, to Algoma, Wisconsin, 

 and 462 during May 9 to August 25, 1932, both south and north of that line. 



One hundred eighty-six bottles or 65,7 percent of those released in 1931, 331 

 bottles or 71.6 percent of 1932 releases, and 517 bottles or 69.4 percent of releases 

 in the 2 years were recovered. 



Recoveries of bottles from both years indicated that the surface currents were 

 somewhat variable, but their general direction was from west to east and pre- 

 dominately northeast in 1931 and northeast and southeast in 1932. 



INTRODUCTION 



Currents have been observed in the Great 

 Lakes by many people. These water move- 

 ments affect navigation, kind of water at 

 intakes, temperatures, plankton, fishes, 

 beaches, and recreation. Currents of Lake 

 Michigan have been discussed in numerous 

 papers. The present study is based on the 

 recovery of drift bottles that were dropped 

 from the research vessel Fulmar, operated 

 by the U. S. Bureau of Fisheries in 1931 

 and 1932. I am greatly indebted to the 

 members of the scientific staff of this 

 vessel who prepared and deposited the 

 bottles. Asa T. Wright drafted all of the 

 figures. 



HISTORY OF LAKE MICHIGAN 

 CURRENT STUDIES 



Harrington (1895) reported, on the basis 

 of recoveries of bottles released in 1892, 

 1893, and 1894 by the U.S. Weather Bureau, 

 that the main current of Lake Michigan passed 

 southward off the west shore, curved east- 

 ward along Illinois and Indiana, and moved 

 northward along the east shore, although 

 certain cross currents and eddies occurred 

 in the center of the lake. Russell (1895) 

 discussed the friction of winds on water 

 movements of the Great Lakes and showed 

 the Weather Bureau's map of Great Lakes 

 currents. Ward (1896) described the Bureau's 

 chart of Lake Michigan. 



