White-tailed deer primarily feed on plants and vegetation. They are classified as herbivores, meaning their diet consists exclusively of plant matter. However, the question of whether they ever consume meat often arises, challenging this conventional understanding. This article explores their nuanced dietary habits, investigating their occasional consumption of animal matter.
Typical Diet of White-Tailed Deer
White-tailed deer are ruminant herbivores, with a digestive system adapted to process plant material. Their diet primarily consists of browse (leaves and twigs of woody plants) and forbs (broad-leaved herbaceous plants). These two categories typically make up over 85% of their diet throughout the year, providing essential nutrients.
Mast, including hard and soft mast like acorns and berries, also forms a significant part of their diet, especially during autumn. While grasses are consumed, they constitute a smaller portion, usually less than 5% of their total intake. Deer possess a narrow snout and a long tongue, which allow them to selectively choose nutrient-rich plant parts.
Their four-chambered stomach, characteristic of ruminants, enables them to break down fibrous plant materials efficiently. This digestive process, involving fermentation by microbes in the rumen, is crucial for extracting nutrients from tough vegetation. Despite this specialized system, white-tailed deer require high-quality, digestible forages to meet their energy and protein needs.
When Deer Consume Animal Matter
Despite their primary classification as herbivores, white-tailed deer occasionally consume animal matter. This behavior is opportunistic, not a regular feeding strategy. Documented instances include deer eating carrion, such as dead rabbits or fish found along shorelines.
Deer have also been observed consuming bird eggs, nestlings, and small rodents like mice and squirrels, especially if injured or young. There are even rare, documented cases of deer gnawing on human bones at forensic research sites. Such occurrences remain uncommon compared to their plant-based food sources.
Why Deer Consume Animal Matter
Deer consume animal matter due to specific nutritional requirements their plant-based diet may not fully supply. A primary reason is the need for minerals like calcium, phosphorus, and sodium. These minerals are concentrated in bones and other animal tissues, supplementing their diet when vegetation is scarce.
For male deer, antler growth demands calcium and phosphorus, as hardened antlers are composed of approximately 22% calcium and 11% phosphorus. Does also have increased mineral needs during pregnancy and lactation, as milk production requires significant calcium and magnesium. Protein deficiencies can also prompt deer to seek animal matter, as protein is essential for growth, reproduction, and body maintenance.