White-tailed deer are highly adaptable herbivores whose diet changes significantly depending on the season and local availability of forage. These animals are opportunistic browsers that consume a wide variety of plants, including forbs, woody browse, and mast crops such as nuts and fruits. Deer will investigate and consume any available food source that offers energy, especially when their primary, most palatable options are scarce. Their foraging behavior is constantly shifting to meet their seasonal nutritional demands and take advantage of temporary food abundance.
Preference for Cranberry Fruit
Deer will eat cranberry fruit, but they are generally not considered a primary or highly preferred food source when compared to other soft mast options. Fruits like apples, persimmons, and acorns are typically sought out first and consumed rapidly when available in the fall. Cranberries often remain on the vine longer, sometimes well into the winter, suggesting a lower initial palatability. Consumption of the fruit frequently increases late in the season, particularly after the berries have undergone several cycles of freezing and thawing. In agricultural settings, such as commercial bogs, deer will take advantage of the dense, concentrated food source, especially if their normal forage is limited or a high deer population leads to increased feeding pressure.
Nutritional Profile and Seasonal Importance
The fruit offers a significant burst of energy, which is particularly beneficial for deer preparing for or enduring the winter months. Cranberries are a soft mast, meaning they are relatively high in simple carbohydrates, primarily sugars, which provide a quick and easily digestible source of energy. This energy is crucial for building the subcutaneous fat reserves necessary to survive periods of cold and low food availability. A 100-gram serving of raw cranberry fruit contains a notable amount of carbohydrates, dietary fiber, and water; while not a major source of protein, the fruit’s energy density makes it an attractive target during late autumn and early winter. Deer have an evolutionary drive to exploit these temporary, high-calorie resources to maximize their energy intake before the nutritional stress of deep winter sets in.
Cranberry Vines and Habitat Interaction
The cranberry plant itself, including the leaves and stems, is classified as browse and is consumed by deer, though often as a secondary food source. True cranberries (Vaccinium species) are low-lying, woody vines typically found in bogs and wetlands, making them a less accessible form of browse compared to the higher branches of shrubs or trees. Highbush cranberry (Viburnum species), a different plant, is a shrub whose stems and leaves are readily browsed, sometimes preferred, by deer. Deer primarily focus on the more tender, succulent leaves and new growth when available. Consumption of the woody vines increases during the winter, when preferred forages like leafy greens and tender shoots are unavailable. In habitats with high deer density or during periods of severe food scarcity, deer will heavily browse the leaves and stems of both true and highbush cranberry plants, occasionally causing damage to the plant stock.