How did the grey squirrel arrive in the UK?
Here is an answer to all those questions on the Red squirrel, grey squirrel blog asking about the introduction of grey squirrels!
Grey squirrels (Scirius caroliniensis) are native to North America and were first released in the UK in 1876 in Henbury Park, Cheshire. It’s not clear why they were introduced and the Victorians had no idea of the risks of introducing non-native species. Perhaps they were just a decorative and interesting “exotic” in the park; part of the fashion for collecting that the Victorians enjoyed so much. There were further introductions around the country and it wasn’t long before it became clear that they had taken to their new home like a duck to water (or a squirrel to trees). Within the space of 25 years, for instance, grey squirrels had colonised an area of some 300 miles between Argyll and Stirlingshire in Scotland.
Although they are bigger and have a reputation for being aggressive, they don’t kill red squirrels and there is evidence that red squirrels were already on the decline because of loss of habitat and disease. The greys have just taken up the space vacated by the reds. The grey’s success (there are about 66 greys for every red) seems to be down to the fact that they are more successful in competing for food. They are also prolific breeders with 2 litters a year of between 3 and 7 kits. This is why extermination programmes haven’t worked – clear the greys out of one area and the neighbouring colonies just move in. Grey squirrels also carry the squirrel pox virus which, although it doesn’t seem to harm the greys, is a serious infection for red squirrels.
Current thinking on conservation for red squirrels is that the best route to boosting numbers is to encourage the habitats most suited to them. The Forestry Commission is working in partnership with various conservation bodies including the Mammal Trust at Kielder Forest in Northumberland.
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1 Comment so far
Ray Lee
22 June, 2008
It’s good to read your level-headed article on the grey squirrel. My opinion, not necessarily shared by everybody of course! is that the red squirrel is native and “cute”. I saw them in 1947 in Kent County, but are now extinct there. Perhaps the disappearance was due to grey squirrels but nobody knows…However, I don’t see that attempts to totally destroy the grey squirrel will succeed. A lot of people like them (including me). I like the red squirrel too, but won’t use it to symbolise any ignorance and anger in a long-running propaganda campaign for prejudice to an “alien” species introduced to this country a very long time ago.
Has anyone yet quantified, in cash terms, the effects of the destruction by the grey on timberlands? Has anyone quantified the effects on timber by the red squirrel, in the very unlikely event that should it become as frequent as the grey squirrel is presently? If people use the term “alien” as a reason for culling etc (much of which will be carried out by psychopathically-disordered persons, not authorised to carry out such a task) then we should include the Little Owl, stop rearing the alien pheasant for shooting (although it will still breed in the wild) and also turn our attention to certain plants and trees that were introduced.
It is in the nature of islands to lose endemic species- this has been well researched. We have developed a zoo mentality, where favourite animals (usually of the cuddly kind- not adders and creepy-crawlies)are protected at the expense of others.
I am for protecting the red squirrel on the basis that there is still hope to do so, but through a programme of common sense: in pockets or areas where this can be achieved. It can’t be a national success. The grey squirrel is here to stay for a very very long time. We should live with it.
R.