Red Squirrel Colour Variations Sciurus vulgaris

Red Squirrel in tree
Red Squirrel with tufty ears
Red Squirrel with red tail
Red Squirrels with usual red coats and red bushy tails, one with tufty ears (photos: Germany, above left and centre, and UK, right).
Red Squirrel with black tail
Red Squirrel with black tail
Red Squirrel with black tail
Some, as above, particularly darker ones, have a jet black tail (photos: UK). (The jet black squirrels seen in southeastern England, spreading north, are variants of the Grey Squirrel.)
Red Squirrel
Red Squirrel
Red Squirrel
The Red Squirrels immediately above with dark coats are in France - photos from Dr Harsha Vardhan Reddy.
Red Squirrel with grey tail
Red Squirrel with grey tail
Red Squirrel with grey tail
Some Red Squirrels, as above, have a grey bushy tail with their red coat (photos: S.E. Kazakhstan 1995).
Red Squirrel with grey head and body
Red Squirrel with grey head and body
Red Squirrel with grey head and body
In harsh winter climates (particularly Scandinavia, Russia and Kazakhstan), the Red Squirrel can have a grey head, body and tail in winter for better camouflage, but the ear tufts give away the true species. Photos taken in Kazakhstan 2018 by Alexandra Makhnina, including her hand.
Red Squirrel winter grey body
Red Squirrel winter grey body
Red Squirrel
The first 2 above, also by Alexandra Makhnina and in the same park in winter, have a grey body and tail (with red tinge) but have retained the red head and limbs. Her third one above is in autumn; the tail remains grey.