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Squirrel Fact File

Last updated: 11 October 2011

Squirrels belong to a large family of small or medium-sized rodents called the Sciuridae.  The family includes tree squirrels, ground squirrels, chipmunks, marmots, flying squirrels, and prairie dogs.  Squirrels are indigenous to the Americas, Eurasia, and Africa.  They were introduced to Australia but were eradicated.  Unlike rabbits or deer, squirrels cannot feed upon cellulose and must rely on foods rich in protein, carbohydrates and fat.

In temperate regions, early spring is the hardest time of year for squirrels because buried nuts begin to sprout and are no longer available for the squirrel to eat and new food sources have not become available yet. During these times squirrels rely heavily on the buds of trees. The squirrel’s diet consists primarily of a wide variety of plant food; this includes nuts, seeds, conifer cones, fruits, fungi and green vegetation. However some squirrels also consume meat, especially when faced with hunger.  Squirrels have been known to eat insects, eggs and young birds

The native European Red Squirrel (Sciurus vulgaris)

Picture of a red squirrel copyright L. Campbell

  • Body length20-22cm
  • Weight 250-300g
  • Colour Variable: Bright red to dark brown,  often with ‘bleached’ tail and ears, with a paler belly
  • Ears:  tufted in winter
  • Habitat: Predominately restricted to coniferous forest
  • Diet:  Seeds, nuts, buds, fungi and berries
  • Breeding 1-2 litters with 3-4 kittens
  • Pox Virus Very susceptible - Most die within 10-14 days of infection
  • Range:  Northern European, however subspecies extend across Asia

The non-native Eastern Grey Squirrel or Grey Squirrel (Sciurus carolinensis)

picture of north American grey squirrel

  • Body length  25-27cm
  • Weight   ~600g
  • Colour Variable: normally grey, often with hints of reds, browns and in some places black.  All generally with a paler belly
  • Ears:  Never tufted
  • Habitat:  Largely broad-leaved forest or parkland.  Can use mature hedgerows and gardens
  • Diet: Wide ranging, similar to red, plus large seeds, acorns, bulbs, flowers, human food and contents of bird feeders.
  • Breeding 2-4 litters with 4-6 kittens
  • Pox Virus Carrier but largely unaffected
  • Range:  Eastern United States and southern Canada.  Introduced to Ireland, UK, Italy and South  Africa (was eradicated from Australia 1973).