Deer are a common sight in many landscapes, and understanding their dietary needs is important for their well-being. While offering food might seem kind, their natural diet is highly specific. Providing inappropriate food sources can lead to serious health issues.
Natural Foraging Habits
Deer are ruminants with a four-chambered stomach adapted to digest fibrous plant material. The rumen, their first stomach chamber, ferments plant matter into absorbable nutrients. This specialized system allows them to process a diet primarily consisting of browse, forbs, and mast.
Browse includes leaves, twigs, and woody stems from trees and shrubs, a significant winter diet component. Forbs are herbaceous plants like wildflowers, providing varied nutrition. Mast refers to nuts and fruits, offering concentrated seasonal energy.
Grasses are consumed when other food sources are scarce, though less preferred due to lower digestibility and nutrient content. A deer’s diet changes seasonally, adapting to available plants and their nutritional content.
Foods to Avoid
Many foods commonly offered by humans are harmful to deer, lacking necessary nutrients and causing severe digestive problems. Human processed foods such as bread, pastries, chips, and candy can lead to bloat or even death. Pet foods, like dog or cat food, are also unsuitable.
Corn, while sometimes used in wildlife feeding, can be dangerous in large quantities. Rapid fermentation of large amounts of corn can cause acidosis, a fatal digestive condition that impairs digestion and nutrient absorption.
Ornamental plants, including azaleas, rhododendrons, yew, and lily of the valley, are toxic to deer. Agricultural crops treated with pesticides or herbicides also pose a risk. Hay and alfalfa, despite appearing natural, are difficult for deer to digest, especially in winter when their digestive systems adapt to a more woody diet.
Understanding Supplemental Feeding Risks
Intentionally feeding deer, even with seemingly appropriate food, carries negative consequences beyond immediate toxicity. Supplemental feed can lead to nutritional imbalances, as even “deer feed” may not provide a complete diet, causing deficiencies or digestive upset that weaken deer and increase their susceptibility to illness.
Feeding stations concentrate deer, facilitating the rapid spread of diseases. Diseases like Chronic Wasting Disease (CWD) and bovine tuberculosis (TB) transmit easily through direct contact or contaminated food sources like saliva, urine, and feces left at feeding sites.
This practice alters deer behavior, leading to dependency on human food and a loss of natural foraging instincts. Deer may become less fearful of humans, increasing aggressive interactions among deer and raising the risk of vehicle collisions.
Concentrated feeding can degrade local habitats through over-browsing, impacting other wildlife species that rely on the same vegetation. Increased deer populations at feeding sites can make them easier targets for predators, affecting the natural balance of predator-prey dynamics. Many areas have made feeding deer illegal due to these ecological and health risks.