Michigan Department of Natural Resources
Research and Development Report No. 263
Institute for Fisheries Research Report No. 1784, 1972
Development of Meromixis in Two Small Lakes in Michigan
W. C. Latta
Two small lakes in the Pigeon River State Forest, Michigan, apparently have become meromictic in recent years. Lost Lake (T. 32 N., R. 1 W., Sec. 2, 3, Otsego County) has an area of 3.7 acres and a maximum depth of 51 feet. Hemlock Lake (T. 33 N., R. 1 W., Sec. 34, 35, Cheboygan County), which lies one-half mile north of Lost Lake, has an area of 4.9 acres and a maximum depth of 59 feet. These lakes are two of a group of seven lakes in the area that have been described by geologists as limestone sinks; i.e., they were formed through the solution of underlying limestone by ground water, accompanied by a settling of the surface layer of sand and gravel, producing a cone-shaped pothole. As a result, the water surface for most of the lakes is 40 to 60 feet below the surrounding land surface (Tanner, 1960). Hemlock is an exception in that the surrounding bank is about 20 feet high on the southeast side and is very low on the north side of the lake. Eschmeyer (1938) in providing general descriptions of all the lakes, indicated an intermittent outlet for Hemlock Lake in 1932. However, since 1948 the lake has been considered landlocked.
The objectives of the following report are: (1) to establish that the lakes are (or have been) meromictic and (2) to demonstrate that the lakes have become meromictic since the original lake surveys in the early 1930’s.