Identity Card

 

Name:European red squirrel
Nickname:Red squirrel
Scientific name:Sciurus vulgaris
Nationality:Italy, Europe, Asia
Residence:Forest of Europe and Asia
Colour:Variable, from red to black


Physical and ecological characteristics

Head-body length (mm) 190-220 mm
Tail lenght(mm)170-200 mm
Weight (g)270-360 g
Longevity (years)5-8 years
Increase in autumn (% of body weight)0-10%
Arboreal activity (% time, annual average)67%
Preferred habitats
Conifers, but it can reach higher densities in mixed broadleaves
Does it prefer acorns?No
Average density 
     Conifer forests
<0,6 ind./ha
     Deciduous forests
<1,0 ind./ha

It is called red squirrel, but the colour may vary.

The dorsal and lateral coloration of the pelage of the red squirrel is variable, from the typical red, to grey and brown, even to black, while the belly is white. The characteristic ear tufts grow during the autumn and are very thick in winter; often they are absent in summer



Behaviour

The red squirrel is one of the few mammals that can be observed while hiking in the woods of the peninsula. The squirrels, in fact, are active during the day and, contrary to what many believe, do not hibernate in winter. The animals start to be active out of the nest at dawn and end their activities late in the afternoon or in the evening, depending on season and food availability.

The squirrels build a nest, easily distinguishable from that of birds, with a spherical diameter of 25-45 cm, made of woven twigs, usually near the trunk or at the bifurcation of branches. The twigs often keep the dry leaves to form an impenetrable layer, while the interior is lined with moss, bark and leaves, to ensure a good thermal insulation and waterproofing. If necessary, they use even tree holes as dens or shelters.
The nests are not exclusive; a single squirrel can use up to 3-4 nests and the same nest can be used by different animals on successive days. Males and females can use the same nest in the breeding season, but then it will be only the female to raise her young in a big and well insulated nest.

Squirrels are solitary animals, but not strictly territorial. Adults usually do not defend part of the forest preventing access to other animals, but adult females that reproduce defend the portion of land that they use more intensively (core area) from the access of other reproductive females. This type of territoriality is called intra-sexual territoriality. The size of the territory occupied by an individual depends on the amount of food available and on how many animals use the same part of wood. It can therefore vary greatly, depending on the type of forest and the annual production of seeds and other food resources. Sometimes the squirrels use territories of 2-3 ha, but in other cases, such as in alpine conifer forests in years with low production of seeds, animals move inside areas of 30-50 ha. In general, males tend to have larger territories than females and adults use larger areas than juveniles.



The mating period is generally between January and June, and births (after a gestation period of six weeks) take place from March to August. In years when food is abundant, females can have two litters a year, but in period of food shortages, reproduction is reduced to a single litter or even absent. After the birth the cubs are lactated for 10-12 weeks before weaning, which makes them independent. Afterwards they leave the mother's territory and can move over several kilometres in search of areas suitable for them, but only 20-40% of juveniles survive their first year of life. When the grey squirrel is present, the survival rate drops dramatically as a result of competition for food and space with the bigger (and earlier born) American squirrels.
In any case, the red squirrels that will be able to find a place to settle, will begin their life in the forest, helping the forest to remain dynamic!

What do they eat?

Squirrels are generalist and opportunist rodents, able to take advantage of many plant food sources, such as buds, young leaves, flowers, berries, bark and lichens. The main food, however, are the seeds and fruits of many species of trees and shrubs. In summer they can also eat mushrooms, both the epigeal ones that grow on the ground (the fruiting bodies of mushrooms such as Boletus and Russula), and the underground ones (that grow in the soil, such as truffles or similar). Occasionally, the squirrels may also eat insects found on leaves and trunks.

The production of seeds of various species of trees vary in a considerable way from year to year, and this has an effect on the population dynamics of the squirrel. The density of squirrels increases substantially over the years in which there are many seeds to eat, but it decreases in years when the plants produce few seeds or nothing at all. There is therefore a strong link between the composition (tree species) of a forest, seed production and behaviour, reproduction and survival of squirrels.