Hazel Dormouse
(Muscardinus avellanarius)
Muscardin
With a body length
of just 6–9cm and a tail of similar length, these small dormice are very
difficult to find and observe and other than by accidental trapping* we
depend on finding their nests or nibbled hazel nuts to record their
presence. Artificial nest tubes can also be useful and are increasingly
used where they are suspected to be present.
They have reddish
brown fur that can vary up to a golden-brown or a yellow-orange-brown
becoming lighter underneath BUT they are grey for the first year of their
life before taking on their adult colours. Eyes are large and black. Ears
are small and not very developed, while the tail is long and completely
covered with hair. They weigh a maximum of 40 gm just before hibernation
in October - November, but as little as 15 gm following hibernation when
they emerge in spring, (April-May).
They are principally a species that lives in
deciduous woodland, dense hedgerows and scrub. When active they tend not
to come down to the ground other than when using a nest. They have nests
that are woven from bark and leaves for resting, (torpor), during periods
of cold weather in spring and summer as well as for raising their young.
These are often built in tree holes or in dense brambles and hedgerows.
With the onset of winter a new nest is constructed for hibernation
purposes and this will usually be at ground level and sheltered by dead
wood, moss or leaf litter where they can curl up tightly for the long
winter sleep.
They have a single
litter of four to five young each summer and have a lifespan of about 5
years. Predation, as with the
They eat berries,
tree seeds, nuts and other fruit with hazelnuts being the main food for
fattening up before hibernation. Other food sources are young leaf buds
and flowers which provide nectar and pollen. They also eat insects found
on the trees they use as a food source, particularly aphids and
caterpillars found high in the canopy.
Besides their
natural predators, (barn owls and other birds of prey, foxes, boars,
marten and so on), that attack them during their hibernation the other
threats come from human forestry and land management practices. In fact,
the destruction of forest edges and brambles, the tearing up of hedgerows
and the replacement of hardwood forests by intensive monoculture of
softwoods has led to a massive loss of their required habitat structure.
*Deliberate trapping
is absolutely illegal for this and any other fully protected species in
