DO PELLET COUNTS INDEX WHITE-TAILED DEER NUMBERS AND POPULATION-CHANGE - A COMMENT

Fuller (1991) concluded that pellet group counts do not index white-tailed deer (Odocoileus virginianus) numbers based on lack of correlation between 5 years of pellet counts and corresponding aerial surveys; however, this conclusion was drawn without knowing the true deer density. His conclusion is based on accepting a null hypothesis from an analysis with negligible power (1 - beta < 0.25). From Monte Carlo simulations based on his data, I estimate that he had a Type II error (accepting H(o) when it is false) rate of 77% when a perfect linear relationship exists between pellet counts and aerial surveys, and a 20% chance of observing a correlation as low or lower than he observed. Although Fuller's conclusion may be correct, his data and analysis do not support his conclusion.