北松鼠

• In nature, the Eurasian red squirrel rarely lives beyond 4 years, although in captivity it may live up to 12. The proportion of individuals older than 4 years, even under favorable conditions, does not exceed 10%.
• The Eurasian red squirrel is the only member of its genus in Russian fauna. It is found in the boreal zone of Eurasia, from the Atlantic coast to Kamchatka, Sakhalin, and Japan.
• In Britain grey squirrels displace red ones, transmitting the lethal squirrel pox virus.
• The Eurasian red squirrel in captivity may reproduce up to two times a year if kept in a spacious enclosure with favorable conditions.
• The Eurasian red squirrel jumps from tree to tree up to 15 meters along a descending curve, controlling its tail like a rudder.
• The Eurasian red squirrel ventures into inaccessible and diverse habitats during migrations, such as tundra, steppes, islands, and mountain peaks.
• The Eurasian red squirrel (Sciurus vulgaris), subspecies S. v. exalbidus, is the largest subspecies with very dense fur. Its winter fur is light, silvery-gray in tone with a bluish-gray mottling.
• The tail serves as a rudder for jumps of up to 3–4 metres and as a blanket in winter.
• The Eurasian red squirrel may have individuals with completely black fur (melanistic), without pigment (albino), and with white patches (piebald).
• In areas with intensive squirrel hunting, the squirrel population is renewed every 3-4 years. Mortality is especially high among young squirrels — 75-85% of juveniles do not survive their first winter.
• During winter, the Eurasian red squirrel uses food stores of other animals, such as the ground squirrel, nutcracker, and mouse, even if they are buried under snow up to 1.5 m deep.