Muscardinus – Hazel dormouse

Can spend up to three-quarters of its life asleep—either hibernating in winter or dozing in torpor during cold spells

One of Europe’s most enchanting small mammals, a symbol of gentle woodland life and natural balance. With its soft golden-brown fur, large black eyes, and fluffy, fully furred tail, it looks more like a storybook character than a wild creature. Found across much of Europe and parts of western Asia, the Hazel dormouse favors ancient woodlands, hedgerows, and overgrown thickets rich in shrubs and climbing plants. Despite its tiny size, it is an expert climber, moving gracefully through tangled branches in search of food, and rarely descending to the ground where predators lurk.

This charming creature is perhaps most famous for its long hibernation habits. From late autumn to early spring—sometimes up to seven months—the Hazel dormouse curls up in a carefully woven nest of leaves, moss, and grass on the forest floor or in a sheltered hollow. During this time, its body temperature drops dramatically, and its heart rate slows to just a few beats per minute to conserve energy. Even outside winter, the dormouse can enter short bouts of torpor on cold or rainy days when food is scarce, essentially taking “mini hibernation naps” to survive. When awake, it’s most active at dusk and night, moving silently among the branches with remarkable agility. Its diet changes with the seasons: in spring, it feeds on flowers, pollen, and insects; in summer, it enjoys berries; and in autumn, it fattens up on hazelnuts, which it nibbles open with perfect precision, leaving a neat, round hole that experts can identify instantly as a dormouse’s work.

The Hazel dormouse plays an important role in maintaining the health of woodland ecosystems. By feeding on flowers and fruits, it aids pollination and seed dispersal while also serving as a food source for owls, weasels, and other predators. Its dependence on dense vegetation and connected habitats makes it an indicator species—where dormice thrive, the ecosystem is usually healthy and diverse.