What does a forest mouse eat in winter? - briefly
In winter, forest mice rely on stored seeds, nuts, dried berries, and bark cambium, supplementing with any accessible insects or larvae. They also consume cached grains and occasional fungal spores when available.
What does a forest mouse eat in winter? - in detail
Forest-dwelling mice shift their diet in the cold months to sources that remain accessible beneath snow and ice. Primary components include:
- Seeds and grains: oak acorns, beechnuts, hazelnuts, and fallen wheat kernels provide high‑fat and carbohydrate content. Mice often cache these in shallow burrows before snowfall.
- Nuts and kernels: pine seeds, spruce cones, and other coniferous remnants are harvested from the forest floor or from tree trunks where bark has been stripped.
- Bark and cambium: thin layers of bark, especially from birch and willow, are gnawed to access the nutrient‑rich cambial tissue.
- Fungi: winter‑active mushrooms and mycelial mats supply protein and essential minerals; mice locate them through scent and tactile cues.
- Invertebrates: dormant larvae, pupae, and winter‑active arthropods such as springtails are captured when they emerge near the soil surface.
- Stored provisions: individuals retrieve previously hoarded food, often arranged in multiple caches to reduce loss from predation or spoilage.
Physiological adjustments support this diet. Metabolic rate declines by up to 30 % to conserve energy, while brown adipose tissue generates heat during brief periods of activity. Foraging is primarily nocturnal and limited to times when snow cover thins or is disturbed by wind, allowing mice to reach ground‑level resources.
Reproductive females prioritize high‑energy items—nuts and seeds—to sustain gestation and early lactation, whereas non‑breeding adults rely more on protein‑rich fungi and insects. Seasonal hormonal changes trigger the mobilization of fat reserves, ensuring survival when external food supplies become scarce.
Overall, the winter feeding strategy combines opportunistic exploitation of available forest detritus, strategic caching, and physiological modulation to meet the elevated energy demands of cold weather.