German Lake is a 71-acre mesotrophic (moderately fertile) lake located in central Otter Tail County approximately one mile south of Underwood, MN. German Lake is the headwaters of the Pomme De Terre River. The immediate watershed is composed primarily of marshland. German Lake has a maximum depth of 46.0 feet; however, 35% of the lake is 15 feet or less in depth. The secchi disk reading during the 2010 survey was 11.1 feet. Previous secchi disk readings have ranged from 9.5 to 18.0 feet.
The majority of the shoreline of German Lake is undeveloped. A state owned earthen public access is located along the southwest shoreline of the lake. Shoal water substrates consist primarily of sand and silt. Stands of hardstem bulrush and common cattail are scattered along the entire lakeshore. Emergent aquatic plants such as wild rice and bulrush provide valuable fish and wildlife habitat, and are critical for maintaining good water quality. They protect shorelines and lake bottoms, and can actually absorb and break down polluting chemicals. Emergent plants provide spawning areas for fish such as northern pike, largemouth bass, and panfish. They also serve as important nursery areas for all species of fish. Because of their ecological value, emergent plants may not be removed without a DNR permit.
German Lake can be ecologically classified as a bass-panfish type of lake and this is reflected in the assemblage of the fish community. Northern pike, largemouth bass, and bluegill are the dominant gamefish species in the fish community of German Lake. The prolificacy of these species can be attributed to the abundance of suitable spawning habitat that is available.
A high-density, slow growing northern pike population exists. Age data indicate that pike reproduction is consistently good. Pike ranged in length from 15.0 to 27.3 inches with an average length and weight of 19.6 inches and 1.7 pounds. Pike attain an average length of 20.4 inches at five years of age.
Data collected from a spring electrofishing assessment indicate that a high-density, slow growing largemouth bass population also exists. Age data suggest that largemouth bass reproduction is consistently good. Largemouth bass ranged in length from 5.1 to 16.0 inches with an average length and weight of 9.7 inches and 0.7 pounds. Bass attain an average length of 12.8 inches at five years of age.
The bluegill population is moderately abundant. Size structure is good with 27% of the bluegills in the trap net sample measuring 7.0 inches or greater in length. Bluegills attain an average length of 7.3 inches at eight years of age.
Anglers can maintain the quality of fishing by practicing selective harvest. Selective harvest encourages the release of medium to large-size fish while allowing the harvest of more abundant smaller fish for table fare. Releasing the medium to large fish will ensure that the lake will have enough spawning age fish on an annual basis and will provide anglers with more opportunities to catch large fish in the future.