A temperate deciduous forest has four distinct seasons - spring, summer, autumn (fall) and winter.

Deciduous trees have leaves that change color in the autumn. These trees lose their leaves in winter.

There are temperate deciduous forests in Europe, Asia, North America, South America (in Chile and Paraguay), Australia and New Zealand.

Gray squirrelThe mammals that live in temperate deciduous forests must adapt to the seasonal changes in temperature that characterize this habitat.

Layers of the Temperate Deciduous Forest

Within a temperate deciduous forest, there are different layers of vegetation.

The highest layer is the canopy layer, which is made up of the tallest mature trees.

The leaves of deciduous trees are thin, so sunlight can reach through the canopy to the layers underneath.

Just below the canopy is a layer of smaller trees. This layer is known as the understory.

Beneath the understory is a layer of dense shrubs - the shrub layer.

Even closer to the ground is a layer of herbs, mosses and ferns. This is called as the field layer.

Soil and litter (debris from decaying organisms) can be found at ground level. Much of the forest litter consists of decaying leaves; therefore, it may be called leaf litter. This is the litter layer or leaf litter layer.

Mammals usually depend more on the general structure of the forest than on any individual plant species.

Important factors include the height of the vegetation, the presence of a shrub layer or a field layer, and the amount of open land available.

For example, the bank vole is usually found in forests with dense herbaceous areas, while the wood mouse lives in forests with an open field layer.


The upper layers of the deciduous forest are mostly inhabited by insects and birds.

However, several species of bat hunt around the tops of trees for flying insects.

Some, such as the brown long-eared bat, also known as the common long-eared bat, pick insects off leaves.

Bats often live in holes near the tops of tree trunks.

Noctule bats can sometimes be heard chattering in tree holes.

The gray squirrel is commonly found in the trees of temperate deciduous forests, where it eats nuts, bark, shoots, fungi and birds' eggs.

It is often found in oak and sweet chestnut forests

A gray squirrel's nest, which is known as a drey (sometimes spelled dray), can sometimes be seen in winter, either high up in a tree branch or where a branch meets the trunk. Dreys are spherical and are composed of twigs and dead leaves.

The red squirrel is another squirrel that lives in temperate deciduous forests.

The fat dormouse, also known as the edible dormouse, gray dormouse, or squirrel-tailed dormouse, resembles the gray squirrel but is smaller.

The fat dormouse is nocturnal (active at night). During the day, it sleeps in a nest built near a tree trunk or in a tree hole.

Like a squirrel, the fat dormouse can make long leaps between tree branches. Both squirrels and fat dormice use their tails for balance.

The hazel dormouse, or common dormouse, is a solitary, nocturnal animal.

It can sometimes be seen at twilight in late summer and in the evening from early autumn. At that time, it emerges from its sleep to eat as many fruits and nuts as it can in order to gain weight before it hibernates between October and April.

Discarded hazelnuts with smooth, neat, round holes provide evidence of the hazel dormouse's presence.

Deer inhabit the shrub layer. For most of the day, they remain hidden. In the evening, they leave cover to graze, and then return to cover at dawn.

They may be active during the day in undisturbed areas.

The roe deer, also known as the European roe deer or the Western roe deer, mostly browses on the leaves, branches, shoots and bark of broad-leaved trees such as hazel, ash and oak.

Fallow deer and muntjac, also known as barking deer, both browse and graze, depending on what type of food is available.

Autumn is the time of rut, or mating season, for fallow deer.

Males mark their territories by using their antlers to fray trees and shrubs and to scrape leaf litter and soil.

Rutting areas are usually beneath trees. They can be recognized by the musky scent of the bucks and the well-trodden paths around the bases of the trees.

Wood mice, bank voles, shrews, hedgehogs, hares and rabbits live in the forests' lower layers - the field layer and the ground layer.

Predators such as weasels, stoats (ermines) and polecats also live here.

The stoat and the weasel are most active during the day. They mostly hunt on the ground.

Their prey consists of small to medium sized mammals, such as rabbits, mice and voles.

Badgers, which inhabit the lower layers, eat earthworms, slugs, insects, snails, grubs amphibians, fruits, nuts, roots and tubers. They will sometimes eat small mammals.

Some mammals of the lower layers are active in both the daytime and the nighttime.

The common shrew, also known as the Eurasian shrew, makes runways and tunnels through the litter and soil.

It must consume its own body weight every day, so it eats furiously for about two hours, then rests, then eats again. It can often be heard making a soft, twittering noise as it searches for invertebrates to eat.

The pygmy shrew also lives in the lower layers.

The bank vole is an active burrower, but gets most of its food from the field layer. Bank voles build nests of grass and moss in tree stumps and under roots.

A molehill is often the only evidence that a mole is in the forest.  Moles themselves are rarely seen above ground.

When a mole digs its complex underground tunnel system, it pushes loose soil upwards to form a molehill.

The mole's large nest mound is usually built in dense undergrowth, where it is difficult to see.

Moles are both diurnal (active during the day) and nocturnal (active at night).

Night in the Forest

Just before dusk, when truly diurnal mammals, such as the gray squirrel, are eating the final meal of the day, nocturnal animals begin to appear.

Bats, such as the noctule, the pipistrelle, the serotine and Bechstein's bat come out from their roosts in tree hollows or emerge beneath foliage in the canopy to chase insects.

They can be heard chattering and squeaking.

The badger emerges from its den, or sett, around dusk.

Its coloring enables other barriers to recognize it in the dark.

The fox feeds on rabbits, hares, small rodents, birds, insects and carrion.

The hedgehog, the fat dormouse, the common dormouse, the wood mouse and the yellow-necked mouse are also nocturnal.

At night, the hedgehog hunts for invertebrates at ground level. During the day, it sleeps in undergrowth. It changes its sleeping site frequently in the summer.

Surviving the Cold

In the autumn, there is a rich supply of food for the mammals of the deciduous forest.

These include nuts, pulpy fruits and fungi.

Even the fox, which is highly carnivorous, takes a share of these.

The gray squirrel stores surplus nuts in the ground, in tree hollows and in dreys.

Buried nuts that are never eaten may germinate and become new trees.

If vegetation is scarce, many mammals, particularly those with specialized diets, die before their first winter.

Many young mammals leave home in autumn. The amount of food that is available from trees and shrubs is a vital factor in their survival.

Some, mammals, such as bats, dormice and hedgehogs, hibernate to conserve energy

During hibernation, an animal's metabolism slows down. Its temperature drops, its breathing slows, and its heart beats less frequently.

Warm days in the middle of winter can be dangerous for hibernating animals. Their body temperatures heat up and they use their stored energy too quickly, with no way to replace it until spring.