Do deer eat rabbits? The short answer is yes, they sometimes do, but this behavior is far from their normal diet. Deer are biologically classified as ruminant herbivores, meaning their digestive system is adapted for processing plant matter. However, they are also highly opportunistic feeders. This occasional consumption of animal matter, including small animals, bird eggs, and carrion, represents a rare, scientifically documented deviation from their typical foraging strategy. Understanding this unusual behavior requires examining the nutritional pressures that drive a deer to seek out non-plant sources of sustenance.
The Standard Deer Diet
Deer are fundamentally “browsers,” meaning they preferentially select the tender shoots, twigs, and leaves of woody plants over low-lying grasses. This feeding style focuses on the most digestible and nutrient-rich parts of vegetation, earning them the classification of “concentrate selectors.”
Their diet is diverse and changes seasonally, incorporating forbs—broad-leaved herbaceous plants—which are often highly digestible and packed with nutrients. Common food sources include the buds, bark, and stems of trees and shrubs, seasonal weeds, and various fruits and nuts, collectively known as mast. The core of a deer’s diet consists of plant-based fiber, energy, and protein, all gathered through browsing.
The Reality of Opportunistic Feeding
Despite their herbivorous nature, deer occasionally consume animal matter, an act that is almost always driven by circumstance rather than predatory instinct. A deer is not equipped to hunt and kill prey, lacking the necessary sharp teeth, body structure, and hunting instincts. Instead, these instances are considered scavenging or highly opportunistic feeding, where they stumble upon an easy meal.
Documented observations include deer consuming bird eggs and hatchlings from ground nests, which are stationary and easily accessible. There are also accounts and video evidence of deer feeding on the carcasses of small mammals, such as squirrels and rabbits. In these rare cases, the small animal was likely already dead or incapacitated, offering a quick source of concentrated nutrients the deer would not normally encounter. This unusual behavior also extends to consuming fish, snakes, and the remains of other deer.
Nutritional Drivers for Consuming Animal Matter
The primary reason a deer consumes animal matter is to compensate for an acute nutritional deficiency that cannot be easily met through plant browsing. The most common drivers are the need for protein and specific minerals, particularly calcium, phosphorus, and sodium. These nutrients are in high demand during certain physiological periods, creating a temporary imbalance in the deer’s body.
For male deer, the rapid growth of antlers requires significant amounts of calcium and phosphorus. The hardened rack is composed of about 22% calcium and 11% phosphorus. Female deer have similarly high mineral and protein requirements during the later stages of pregnancy and throughout lactation while nursing fawns.
In some environments, especially where natural forage is poor or during harsh winters, the high concentration of these limiting nutrients in animal tissue or bone can be a powerful attractant. This drive explains why deer have been observed chewing on shed antlers, bones, and spent shell casings, all of which offer a dense mineral supplement unavailable in their typical plant diet.