The Grey Squirrel

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A grey squirrel foraging for food.

The Eastern Grey Squirrel (Sciurus carolinensis) originates from North America and is easily identified by its grey colouring and bushy tail that is fixed to its back. They source their food from foraging along the forest floor and by climbing trees where they mostly find fruits and nuts or fungi but occasionally they consume eggs or even insects as their diet is omnivorous. Squirrels have even been know to eat young snakes as they have extremely sharp claws which aid hunting and climbing. Their nests are football sized structures made from whatever they can forage such as twigs, leaves and grass and have the name a drey. A mother and her young will live in the drey but apart for that squirrels don't really interact with other members of their species. They are relatively solitary animals and it is rare to find a scurry (group) of them.

 They grow to about 30cm and their tails can reach lengths of 25cm. The clever adaptation of a tail enables to squirrel to balance whilst climbing or jumping between trees and being able to land. It is also used as rudder whilst the squirrels swim which I didn't know that squirrels had the ability to do. They swim as part of their instinctive migratory behaviour. Grey squirrels used to take part in mass migrations across parts of America and now their instinct allows them to swim to find food or shelter. The tail is also used as a warning to fellow squirrels in the presence of a predator. If the tail is pulsed three times it acts as a warning to other squirrels in the area telling them to get away or hide. It is also used for other forms of communication not just as a danger call and is especially relevant in breeding season where the tail is used to attract, but also reject, a partner. They breed when food is abundant in the early months of the year and could possibly have another litter in summer which has lead to their success and high population numbers - estimated 2,520,000 in the UK alone.

 Grey squirrels were introduced to the UK in the 1870s when they were imported to estate owners who saw the grey squirrel as a luxury or fashionable item that would increase the value of their estate but little did they know the danger they could cause to the indigenous Red Squirrel (Sciurus vulgaris). Grey squirrels carry the squirrelpox virus or more commonly know as squirrel pox a virus which they themselves can fight off but because red squirrels hadn't been exposed to it before it can be fatal to them. Numbers of red squirrels have decreased rapidly since the introduction of grey squirrels to the UK leaving only 140,000 of the species in the UK which is a relatively low number compared to the over 2.5 million grey that are here.

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