Species name: Sciurus carolinensis

The Eastern Grey Squirrel is a species of tree squirrel which are considered a pest, due to being an invasive species which can cause damage to trees and threaten native red squirrels (BPCA, 2018). Grey squirrels are often 24-26cm from head to body whilst weighing 400-600g, which is nearly double the average weight of a red squirrel. They are identified by their mostly grey fur, with patches of red-brown fur and a bushy tail, which is used for balance.

Grey squirrels were introduced to the UK from North America during the Victorian era as an ornamental species to populate stately homes and parks by wealthy landowners, with them first being introduced in 1876, Henbury Park in Cheshire (British Red Squirrel, 2025). Which has now led to there being an estimated 2.7 million grey squirrels in the UK (Woodland Trust, 2020).

They are omnivores, so their diet consists of nuts, seeds and berries, and to prevent this food from being stolen, grey squirrels will often pretend to bury its nuts, to trick other squirrels that are watching (Woodland Trust, 2020). However, a lot of the food is buried, after being collected in autumn, so that it can be eaten in winter, when there is less food available.

Grey squirrels will often live close together, as they are not territorial, yet dominant hierarchies exist amongst them (Woodland Trust, 2020). They breed during the spring and summer, and if there is enough food, the female grey squirrels will often produce two litters where the young are referred to ‘kittens’ (Southwick Country park, 2018), with up to four young per year in nests called ‘dreys’. Then after two months, the young will leave their nests to search for solid food.

The introduction of this species has had a largely negative impact on the red squirrels, which are native to the UK, as they often compete for food, as grey squirrels are often able to eat seeds and nuts which haven’t fully ripened, therefore getting to the food before the red squirrels (DAERA, 2015). As well as this, Grey Squirrels often carrying a virus called squirrelpox, which is deadly for red squirrels. This had led to the last populations of red squirrels being in places where there are no/ few grey squirrels, such as in Scotland, Wales and Northern Ireland (Woodland Trust, 2020).

There has been targets to try and remove Grey Squirrels from the habitats which are most suitable to the Red Squirrel. This is being attempted in several different methods, such as trapping, shooting and tree protection to try and increase the Red Squirrels populations again.

With the Grey Squirrels being native to North America, Native Americans often believe that if someone is visited by a squirrel, it will grant that person swiftness and preparedness, as those are the characteristics of a grey squirrel. It was also thought that if one was seen, it means that they should be prepared for a rough winter. (Fairmont State University Library, 2021). Along with is, the early Celtic’s associated the squirrel with the goddess of war, Queen Medb, as she was thought to have squirrels on her shoulder, who acted as messengers between earth and the sky (Wildlife Online, N/D)

References

“10 Facts about Grey Squirrels.” Southwick Country Park Nature Reserve, 2 Dec. 2018, southwickcountrypark.com/2018/12/02/10-facts-about-grey-squirrels/. Accessed 4 Dec. 2025.

Baldwin, Mark. “Grey Squirrel | Wildlife Online.” Www.wildlifeonline.me.uk, http://www.wildlifeonline.me.uk/animals/species/grey-squirrel. Accessed 4 Dec. 2025.

DAERA. “Controlling the Grey Squirrel Population | Department of Agriculture, Environment and Rural Affairs.” DAERA, 24 Aug. 2015, http://www.daera-ni.gov.uk/articles/controlling-grey-squirrel-population. Accessed 4 Dec. 2025.

“Fairmont State University Library: The Wildlife of Wonderful West Virginia: Gray Squirrel.” Fairmontstate.edu, 2021, library.fairmontstate.edu/c.php?g=1108744&p=8085833. Accessed 4 Dec. 2025.

“Grey Squirrels.” British Red Squirrel, http://www.britishredsquirrel.org/grey-squirrels/.

“Pest Advice for Controlling Grey Squirrels.” Bpca.org.uk, 2018, bpca.org.uk/a-z-of-pest-advice/squirrel-control-how-to-get-rid-of-squirrels-bpca-a-z-of-pests-/188983. Accessed 2 Dec. 2025.

Woodland Trust. “Grey Squirrel.” Woodland Trust, 2020, http://www.woodlandtrust.org.uk/trees-woods-and-wildlife/animals/mammals/grey-squirrel/. Accessed 4 Dec. 2025.