Abstract: Although nutritional status in response to controlled feeding
trials has been extensively studied in captive white-tailed deer (Odocoileus
virginianus), there remains a considerable gap in understanding the influence
of variable supplemental feeding protocols on free-ranging deer. Consequently,
across the northern portion of the white-tailed deer range, numerous property
managers are investing substantial resources into winter supplemental-feeding
programs without adequate tools to assess the nutritional status of their populations.
We studied the influence of a supplemental winter feeding gradient on the protein
and energy status of free-ranging white-tailed deer in the Adirondack Mountains
of New York. We collected blood and fecal samples from 31 captured fawns across
3 sites that varied considerably in the frequency, quantity, and method of supplemental
feed distribution. To facilitate population-wide comparisons, we collected fresh
fecal samples off the snow at each of the 3 sites with supplemental feeding
and 1 reference site where no feeding occurred. Results indicated that the method
of feed distribution, in addition to quantity and frequency, can affect the
nutritional status of deer. The least intensively fed population showed considerable
overlap in diet quality with the unfed population in a principal components
ordination, despite the substantial time and financial resources invested in
the feeding program. Data from fecal samples generally denoted a gradient in
diet quality and digestibility that corresponded with the availability of supplements.
Our results further demonstrated that fecal nitrogen and fecal fiber, indices
of dietary protein and digestibility, can be estimated using regressions of
fecal pellet mass, enabling a rapid qualitative assessment of diet quality.