Wayne H. Schacher

Wood duck (Aix sponsa) nest boxes (N = 190) were placed along the lower Holston River and the lower French Broad River in eastern Tennessee and were maintained and checked from 1976 to 1979. Wood ducks used 1.3% of the boxes inspected during the 4-year study. Night brood counts ranged from 0.42 to 0.68 broods/km of river and did not indicate an increase in brood production. Nest box use and brood production in this study were significantly less than reported for a study on the upper Holston River. We believe that aquatic vegetation, valuable as a food base for wood duck broods, was a more...

Muskrats (Ondatra zibethicus) were collected from river and creek study areas in East Tennessee from July 1972 to June 1973. An imbalance in sex ratios was found to be seasonal and an overall sex ratio approaching 1:1 is likely the actual case. Significantly heavier body weights of river versus creek animals likely reflects the more abundant and/or higher quality food supply present on the river than on the small creek. Adult male muskrats from the river tended to exhibit expected patterns of deposition and utilization of internal body fat, with increased fat levels from spring through...

Muskrats, Ondatra zibethicus, (360) were collected from river and creek study areas in East Tennessee from July, 1972 to June, 1973. Data were recorded on reproductive parameters. Maximum values for testis length and width occurred in August, whereas maxima for testis volume and weight were in May and August, respectively. Evidence indicated that sperm were present in the adult males year-round. Maturation of follicles began in January in adult females; mature follicles were present in late February and March, and the first corpora lutea of pregnancy were found in April. Maximum...