The Red Fox (Vulpes vulpes) is a globally successful animal due to its highly flexible feeding habits. While often classified within the order Carnivora, the fox’s diet makes it a true omnivore, consuming a vast array of resources across diverse habitats. This adaptability has allowed the species to thrive from the Arctic Circle to North Africa. Its survival relies on an opportunistic approach to finding and processing any available caloric source, ensuring it meets its daily requirement of roughly one pound of food.
The Foundation of the Fox Diet: Small Mammals and Birds
The primary, high-calorie components of a fox’s diet in rural and natural settings are small mammals. Rodents like voles, mice, and shrews are staples, often supplemented by larger prey such as eastern cottontail rabbits and muskrats. A fox’s diet may also include ground-nesting birds, their eggs, and young chicks when they are vulnerable during the nesting season.
To secure this high-protein prey, the fox uses a distinctive “mousing pounce.” The fox will stand motionless, listening for the faint sounds of rodents moving beneath the soil, grass, or snow. Once the prey’s location is pinpointed, the fox leaps high into the air and drives its forepaws down with force to pin the animal to the ground.
The fox may even utilize the Earth’s magnetic field to orient its jump, maximizing its success rate. Foxes are more successful when pouncing in a north-easterly direction, particularly when prey is hidden under a thick layer of snow. This technique allows the fox to efficiently capture animals that would otherwise be inaccessible.
Essential Supplements: Invertebrates, Fruits, and Vegetation
Invertebrates and plant matter act as important supplements to the fox’s meat-based diet. Insects, including beetles, crickets, and grasshoppers, are frequently eaten, and earthworms are an abundant, easily acquired food source, especially after rainfall. In some desert habitats, insects can even become the single largest component of the fox’s diet.
Plant materials like fruits and vegetation provide carbohydrates, hydration, and fiber, particularly during the late summer and autumn months. Foxes commonly forage for wild berries such as blackberries and raspberries, along with grapes, apples, and acorns. A fox’s scat during the autumn will appear dark purple from the sheer volume of berries consumed.
Environmental Adaptability: Urban Foraging and Scavenging
The fox demonstrates its ultimate dietary flexibility when it colonizes human settlements, where its food sources shift toward opportunistic scavenging. In highly urbanized areas, the percentage of human-derived food in a fox’s diet can exceed half of its total intake, sometimes reaching 80% in large cities. This shift involves exploiting unprotected garbage, discarded food scraps, and compost piles.
Urban foxes are adept at tearing open unsecured trash bags and feeding at bird feeders, where they consume seed, fallen nuts, and suet. They also frequently access pet food left outdoors, which provides a reliable, high-energy meal. However, this reliance on human sources introduces a lower-quality diet of household refuse, which can include non-nutritive items like plastic and packaging materials.
Despite the abundance of scavenged food, the urban fox remains an active hunter, preying on prolific city rodents like rats and mice. The close proximity to humans carries risks, including a higher incidence of traffic-related injuries and increased exposure to diseases such as mange. The ability to switch between hunting natural prey and effectively scavenging for human refuse allows foxes to maintain stable populations in even the most challenging city environments.
Seasonal Changes and Food Caching Behavior
The composition of the fox diet changes with the seasonal availability of resources across its territory. During the spring and summer, the diet is richest, with a higher proportion of newly available items, including bird eggs, young mammals, and insects. As the summer transitions into autumn, the fox capitalizes on the abundance of ripe fruits and berries to build up fat reserves for the leaner months.
In winter, when small prey becomes less active and plant food disappears, the fox’s diet shifts toward increased scavenging and a greater reliance on carrion. This seasonal scarcity makes the behavior of “caching,” or food storage, a survival strategy. Caching involves burying excess food, such as a surplus of mice or a large piece of meat, in numerous small, shallow holes.
The fox will cover these caches with soil, leaves, or snow, sometimes marking them with urine to aid in future retrieval. This behavior ensures a dispersed supply of food that can be accessed during periods when hunting is unsuccessful or energy expenditure must be minimized. Studies show that foxes typically recover most of their caches within a day or two, demonstrating a remarkable memory for their hidden food stores.