The whitetail has a sophisticated four part stomach that digests everything from cactus to acorns, and produces heat as a by-product. They can live in a wide variety of habitats because they eat so many different types of foods. Whitetails require an abundant food supply consisting mainly of forbs and grasses. In the winter, deer eat crops and crop residue, nut, buds and twigs.
Whitetails can survive for a long time without water if their food has a high water content.
The less water available in the food, the more they must depend on streams, lakes, potholes, creeks and other surface water sources. Lack of water will limit deer populations.