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elevation of 883 msl). They identified 15 plant species: 8 rooted submergent species; 4 emergent species; and, 3 floating species. Nine of the species they observed rank as excellent to good waterfowl foods (e.g., slender and softstem bulrush, chara). The Service didnot conduct quantitative vegetation surveys for nearly 30 years after contaminants were discovered in the early 1980s. Recent observations by Refuge staff found 10species of submergent plants and 14 species ofemergent plants.Coontailwas the dominant submergent species and cattailwas the dominat emergent species. Noteably, cattail was present in less than 20% of the basinsampling locations. (USFWS 13).White water lilly was found in about 35% of the sampling locations. Waterfowl migration surveys conducted on Round Lake from 1975 through 1978 routinely recorded large flocks of waterfowl numbering between 1,000and9,000individuals.The most abundant species were diving ducks (e.g., ring-necked duck, scaup, merganser, bufflehead,coot) with slightly fewer dabbling ducks (e.g., American widgeon, mallard) (Sherburne National Wildlife Refuge field reports). Round Lakewaterfowl observations during 2010,2011, and 2012fallmigration showed that use of the lake is variable across the migration period. Numbers of waterfowl observed on the lake at any one time ranged from a few hundred to a few thousand (USFWS 2010,2011,2012).Diving ducks were more abundant than dabbling ducks. In 2012, Round Lake had disproportionately high duck use (more than 10 times) compared to nearby waterbodies. Diving ducks used Round Lake in higher proportions than nearby waterbodies. Following the remediation of contaminants in the Round Lake basin, water management activities on the Round Lake Unit will focus on maintaining healthy emergent and submergent plant communitiesas well as maintaining water quality. Attaining these habitat goals will provide a plant and animal food base and suitable cover to support not only habitat requirements for waterbirds in migration but also the annual lifecycle needs of several migratory and resident wildlife species.This will require active water management. There are some key elevations and concepts related to water level management. At an elevation of 892.0 msl water starts to cause damage to adjacent properties. This could be characterized as a “maximum” water elevation, although it is possible that runoff from significant rainfall events may cause this elevation to be exceeded. An elevation of 890.0 msl is the historical “normal” water level for the lake(Anon. 1947). This elevation is a likely target for water elevations to maximize use of emergent vegetationbydabbling ducks during fall migration. At this elevation we would expect about 6 –7% of the lake to have emergent vegetation. The sill of the existing water control structure is887.0 msl. This would be a likely maximum “draw down” elevation because water levels cannot be movedlowerthan this without special techniques, such as pumping or siphoning.Historical Round Lake observations have recorded water levels as low as 885 –886 msl due to evaporation during natural “droughts.” Prior to the Service’s decision to hold water levels in Round Lake highdue to the contaminated sediments, water levels were regularlytargeted to this 887.0 levelfor management purposes.Based on recent bathymetry informationshown in Table 1(Wenck2010),at an elevation of 887.0msl, 90 % of the basin would still be covered with water. 8/6/2013 10 USFWS RLMP