Alternative Names (Synonyms)

• Grey squirrel
• American grey squirrel
• Eastern gray squirrel (North America)
• Cat squirrel (North America)
• Migratory Squirrel (North America)
• Gray Squirrel
• Ecureuil gris (French)
• Grauhörnchen (German)

Names for new-borns / juveniles

General Appearance

Similar Species

• Differentiated from Sciurus vulgaris - Eurasian red squirrel: larger and sturdier, with slightly longer skull, no ear tufts, mainly grey colouration (B142, B144, B148)
• Differentiated from Myoxus glis - Fat dormouse: much larger size B142

References

Species Author

Major References

• B51, B141, B142, B143, B144, B147, B148, B221
• D30

Husbandry references:
B151, D24

• Wildlife and Countryside Directorate, Department of the Environment, Transport and the Regions (DETR)
• The Mammal Society
• Mammals Trust
• Humane urban wildlife deterrence

• --

TAXA Group (where information has been collated for an entire group on a modular basis)

Parent Group

• Squirrels (Rodents)

Specific Needs Group referenced in Management Techniques

• Squirrels (Rodents)

Husbandry Information

Notes

• Accommodation of Casualty Squirrels
• Hand-rearing Squirrels
• Catching and Handling of Squirrels
• Feeding of Casualty Squirrels
• Release of Casualty Squirrels

Measurement & Weight

Head

Skull: Slightly longer than that of Sciurus vulgaris - Eurasian red squirrel and shallower (B142, B148).

Nose:

Ears: no conspicuous ear tufts (B142, D30).

• I 1/1 C 0/0 P 1-2/1, M 3/3 (B142, B147).
• Cheek teeth rooted, low-crowned, quadrate, cuspidate. (B142, B147).
• Deciduous lower and second upper premolars shed at 16 weeks of age; others not deciduous (B142).

Legs and Tracks

Tail

Length: 8-9.4in./20-23.5cm (B144); about 21cm (B148); 19.5-24.0cm mean 22.0cm (B142).

Coat / Pelage

• Dorsal: overall grey, with mid-dorsal area more brown.
• Flanks and limbs: more chestnut/russet
• Ventral: white
• Tail: hairs banded black and brown, indistinctly white fringed 
• Ears: grey

Winter: thicker coat

• Dorsal grey with midline and head more yellow-brown.
• Tail dark grey with white fringe
• Ears: back surface white, short tufts. 

(B142, B148, D30)

• Dark grey and black (melanistic) individuals common in northern part of North American range 
• Melanistic forms rare in Britain
• Albinos rare. seen in urban areas in North America, also in England (Kent, Surrey, Sussex)
• Erythistic (reddish) forms seen occasionally in south-east England.

(B142, B143)

• Body moult twice yearly.
• Spring moult: from front to back
• Autumn moult: from back to front.
• Ear tufts moult once yearly, with new hairs growing in late summer/autumn, through to December
• Tail moult once yearly, with new hairs growing in late summer/autumn.

(B142)

Neonate (New-born) Characteristics

Detailed Anatomy Notes
(Summary information provided for pertinent species-specific data cross-referenced in Wildpro)

Natural Diet

• Seeds, plant material.
• May eat 60-80g seeds per day (laboratory studies)

(B142)

Detailed Physiology Notes
(Summary information provided for pertinent species-specific data cross-referenced in Wildpro)

Feeding Behaviour

Bury food (nuts, acorns) in multiple small caches

(B142, B147, B148)

Parental Behaviour

Social Behaviour / Territoriality

• Density may be 5-50 per hectare
• Home range may be only 0.5 hectare.
• Male home range generally larger than that of female
• Home range size affected by food supply, habitat type, population density.
• Smaller inter-individual distances than for Sciurus vulgaris - Eurasian red Squirrel.
• Foraging area may move in autumn due to differences in food availability 
• Hierarchy within and between sexes
• Fights rare, but include wrestling and chasing with biting
• Peak aggression during breeding and dispersal
• Groups of adults may huddle in nests, particularly in winter

(B142, B147)

Sexual Behaviour

• Promiscuous.
• Little courtship.
• Males may congregate on home range of oestrous female, and fight.
• Mating chases of several males after one female may occur; dominant male presumed to mate with female.
• Pair separate after mating.

(B142, B147),

Predation in Wild

• Pine marten, wild cat, owls, raptor (e.g. goshawk).
• Foxes, cats, dogs while on ground.
• Stoats may take nestlings.

(B142)

Activity Patterns

• Arboreal, but less so than Sciurus vulgaris - Eurasian red squirrel
• Agile at traveling along branches
• Come to ground to forage, and to bury food
• Do not hibernate
• In stormy/very cold weather may remain in nest until need to leave to find food

(B142, B144, B147, B148)

• Diurnal, with activity peaks early morning and late afternoon, but midday in colder areas in winter.
• May feed on moonlit nights in summer and autumn

B147

General Habitat Type

• Forests, parks (B144)
• Broad-leaved woodland, mainly with many tree species and particularly mature oak-hickory forests (North America).
• Britain: Wide range of habitats, particularly mature broad-leaved forests (oak, beech, sweet chestnut, hazel), but also mixed woodland (broad-leaved/coniferous), mature coniferous, hedgerows, parks, gardens and urban areas with mature trees.

(B51, B142, D30)

Nests / Burrows / Shelters

• In tree hollow (ground level to about 12 metres) or ball/dome shaped nest of leaves and twigs built in branches.
• More than one nest 
• Domed structure, side entrance. lines with grass and leaves 
• Leafy platform on branches in summer

(B142, B147, B148)

Distribution and Movement (Migration etc.)

• Europe: Great Britain, Ireland, Northern Italy

• South Africa

(B51, B142, B143, B147)

Intraspecific variation

• Five subspecies recognised in North America.
• Size cline in North America: body mass increases further north.
• Black squirrels in north-eastern part of North American range.

(B143)

Conservation Status

• No international conservation status (B143)

• Important game animal in North America (B143)

• Forestry pest in Britain and Italy (B143).

• In Britain: introduced 19th century and early 20th century; common, increasing population and range. Pre-breeding population estimate of about 2,520,000, with 2,000,000 in England, 200,000 in Scotland, 320,000 in Wales. Population estimate of this widely-distributed species was based on a limited amount of data and considered likely to be inaccurate by up to 50% in either direction (B221).

• This species is listed on Schedule 9 - Part 1 (Animals and plants to which Section 14 applies (ie. may not be released into or grown in the wild) ) of the LUK2 - Wildlife and Countryside Act 1981 of the United Kingdom. (W5.Oct01)
• See: Destructive Imported Animals Act 1932 (Mentions importation of "hares")