Key points are not available for this paper at this time.
Gary R. Hepp, Robert J. Blohm, Ronald E. Reynolds, James E. Hines, James D. Nichols, Physiological Condition of Autumn-Banded Mallards and Its Relationship to Hunting Vulnerability, The Journal of Wildlife Management, Vol. 50, No. 2 (Apr., 1986), pp. 177-183
Hepp et al. (Tue,) studied this question.