Types of Squirrels in Europe and Croatia

Europe is home to two main species of squirrels: the Eurasian red squirrel (Sciurus vulgaris) and the American gray squirrel (Sciurus carolinensis). Gray squirrels are found exclusively in Great Britain and Italy, while red squirrels are present in other European countries. The introduction of gray squirrels poses a significant threat to red squirrels due to competition for resources. Gray squirrels are generally more aggressive and adept at securing food and habitat, which compromises the survival of red squirrels. Moreover, gray squirrels can carry the squirrel pox virus, to which red squirrels are vulnerable, leading to potential fatal outbreaks among the red population.

Introduced to Europe from North America in the mid-19th century as exotic pets and ornamental animals, gray squirrels have since proliferated and displaced native red squirrels in many areas, leading to a decline in the red squirrel population across Europe. This is partly because gray squirrels thrive in deciduous forests where acorns, their primary food source, are abundant. In contrast, red squirrels, which struggle with digesting acorns, have adapted to coniferous forests and rely on fruits like pine nuts, which are less abundantly available but provide year-round sustenance, explaining their sparse populations.

Gray squirrels are considered an invasive species in Europe, prompting many countries to implement measures to control their population and spread. In Great Britain and Italy, for instance, extensive programs are underway to manage the gray squirrel population and restore the native red squirrels to their traditional habitats.

Eurasian red squirrels typically measure 18 to 24 cm in body length, with a tail slightly longer, ranging from 15 to 20 cm. They are easily identifiable by their thick red-brown fur on the back and a lighter white belly and chest. These squirrels are adaptable to various environments, including forests, parks, and urban areas.

Red squirrels are diurnal, with peak activity in the early morning and late afternoon. While generally social, male red squirrels can be territorial and aggressive towards other males. Their diet is mainly herbivorous, consisting of seeds, nuts, fruits, berries, flowers, tree bark, sap, leaves, and fungi. During food shortages in winter, they may also consume insects and bird eggs.

Expert climbers and jumpers, Eurasian red squirrels can leap distances of 2-3 meters between branches. In autumn, they gather and store food for winter, hiding supplies in various locations for later consumption. Unlike some mammals that hibernate, red squirrels do not hibernate but instead prepare food stores and build nests in trees to shelter from the winter cold. On colder days, they may reduce their activity but continue to forage near their nests.

These squirrels construct nests from twigs, leaves, and moss, typically in treetops, and can live up to 6 years in the wild and about 10 years in captivity.