What do polar mice eat? - briefly
Polar mice feed mainly on tundra vegetation—mosses, lichens, and seeds—and supplement this with insects when they are available. Their diet mirrors the scarce plant resources and seasonal arthropod abundance of Arctic environments.
What do polar mice eat? - in detail
Polar rodents inhabiting Arctic regions rely on a diet that combines plant material, invertebrates, and occasional animal protein. The primary components are:
- Tundra vegetation: mosses, lichens, and dwarf shrubs such as Salix and Betula provide carbohydrates and fiber. Seeds from grasses and sedges supplement these sources during the brief summer.
- Arthropods: springtails, mites, and beetle larvae constitute the main protein intake. These organisms are abundant in moist microhabitats under snow and within thawed soil layers.
- Nematodes and microscopic worms: found in the upper soil profile, they add essential amino acids and lipids.
- Occasional carrion: dead insects, bird eggs, and small vertebrate remains are consumed when available, offering high‑energy fats.
Seasonal shifts dictate food availability. During the polar night, rodents increase reliance on stored body fat and consume frozen plant parts that retain sufficient nutrients. In summer, foraging expands to include freshly sprouted shoots and a higher abundance of invertebrates. Activity patterns adjust to temperature: most feeding occurs under the insulating snow cover, where temperatures remain above freezing, allowing metabolic processes to continue.
Digestive adaptations support this varied diet. A cecum enlarged for fermenting fibrous plant matter enables extraction of energy from mosses and lichens. Enzymatic activity targeting chitin and keratin facilitates digestion of arthropod exoskeletons and occasional animal tissue. The combination of high‑fat reserves, flexible foraging behavior, and specialized gut morphology ensures survival in an environment where food sources are both scarce and highly seasonal.