The red fox (Vulpes vulpes) is an adaptable omnivore, but winter presents a substantial obstacle to its survival, forcing an opportunistic shift in its diet. Cold temperatures and scarce resources necessitate a focus on high-calorie foods and sophisticated hunting strategies. Their winter diet relies on a mix of active predation, determined scavenging, and stored reserves to meet the high energetic demands of staying warm. The availability of food during this season directly influences their health and reproductive success in the coming spring.
Hunting Small Mammals and Birds
Small rodents are the primary targets of a fox’s active hunting in winter, as they provide a consistent and relatively high-calorie food source. Voles, mice, shrews, and sometimes rabbits remain active beneath the insulating layer of snow, making them the staple of the winter menu. The fox possesses acute hearing, allowing it to pinpoint the exact location of these small mammals rustling or moving deep beneath the snow cover.
Foxes use a specialized hunting technique known as “mousing” to capture this hidden prey. The fox listens intently, often tilting its head to triangulate the sound, before launching itself high into the air and executing a characteristic, steep pounce. This precise, head-first dive allows the fox to penetrate the snow and surprise the prey. Small birds that are weakened or struggling in the severe cold, or those roosting on the ground, are also taken as supplementary prey when the opportunity arises.
Relying on Scavenging and Plant Matter
When active hunting is less successful or requires too much energy, scavenging becomes a reliable source of sustenance. Foxes readily consume carrion, particularly the remains of larger ungulates like deer or moose that may have died naturally or been left by hunters and larger predators. In some boreal forest environments, ungulate remains can account for a significant portion of the winter diet, sometimes exceeding 40% of food consumed.
Urban and suburban foxes often rely on human activity for easy meals, foraging through refuse and consuming discarded food scraps. This opportunistic scavenging can include items like pet food left outdoors or even bird seed, which provides easily accessible calories with minimal energy expenditure. While not a preferred food source, plant matter like hardy berries, seeds, and fruits that persist into winter will be consumed if other sources are scarce, acting as a dietary filler.
How Foxes Store Food and Manage Energy
A primary behavioral adaptation for winter survival is the practice of caching food, which is the temporary burial of surplus food items for later consumption. Because foxes have relatively small stomachs for their body size, they often hunt more than they can eat in a single sitting, and they will bury this extra food against periods of scarcity. The fox typically digs a shallow hole, places a small, single-meal portion of food inside, and covers it carefully with soil or snow.
Foxes generally practice “scatter caching,” burying individual food items in many different locations across their territory rather than hoarding everything in one spot. This strategy minimizes the risk of losing their entire reserve if another animal discovers a cache. Their ability to remember these scattered locations allows them to retrieve the stored food efficiently during lean winter days. Foxes also manage their energy by reducing their activity levels during the coldest periods and utilizing their thick winter coat and bushy tail to conserve heat while resting.