An evaluation of some components of wood duck habitat at John Sevier Lake, Hawkins County, Tennessee

The study was conducted on John Sevier Lake, a small TennesseeValley Authority impoundment near Rogersville, Tennessee. The lake is 5.5 miles in length and covers about 810 acres.The objectives of this study were: (1) to describe the aquatic and emergent vegetation of John Sevier Lake, and (2) to relate the distribution of wood ducks (Aix sponsa) on the study area to the various components of the habitat. Field work was begun in March, 1967, and concluded in June, 1968. Five aquatic and five emergent plant communities were designated by visual inspection.- A map showing the location of the aquatic communities was prepared. Aquatic vegetation was important in the diet of wood ducks.Biomass of each aquatic community was estimated in pounds per acre.Mill-acre plots were taken in areas where the water was less than five feet deep, while 0.1-mi1-acre plots were taken in deeper areas. A sampling device was improvised for use in these deeper areas.In the emergent communities, square-meter quadrats were taken along systematically established transect lines. Density, basal area,crown cover, and maximum height of vegetation were recorded. Cattail and blue-stemmed bulrush were the most prevalent emergent species.Results indicated that the best cover was found where varied species composition and varied plant sizes prevailed. The abundance of floating masses of uprooted aquatic plants produced in the Holston River upstream from the study area was the primary attractant for wood ducks at John Sevier Lake. Shoreline cover significantly affected the distribution of theducks. Wooded shorelines received the highest use, while shoreline adjacent to cultivated or idle fields were avoided. Emergent vegetation was neither preferred nor avoided by wood ducks at John Sevier Lake