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American Grey Squirrel - Sciuris carolinensis




The grey squirrel’s preferred habitat is mature woodlands however they are also widespread throughout urban and rural areas.



The grey squirrel is a direct threat to the native red squirrel. It also has a negative effect on our woodlands and the forestry industry.



The grey squirrel can is found throughout Ireland although it is not present to the West of the Shannon. Sciurus carolinensis has been known to cross at bridges in other parts of the country.


What does it look like?

The grey squirrel is notably larger than the native red squirrel. It has a distinctive, long, bushy tail and short front legs. The majority of grey squirrels have ‘chestnut’ markings on their paws, hips, and faces, which can lead to misidentification. In winter, they have a thick grey/silver coat on the upper side of their bodies with a white under side.



The grey squirrel out-competes the native red squirrel in our deciduous forests. It is a known vector of the parapox virus that is fatal to the red squirrel. Direct competition with the red squirrel in England and Wales, has led to the extinction of the red squirrel in these countries. The grey squirrel is also potentially an economic hazard, as it strips the bark from trees in times of food scarcity. This has potential implications for the forestry industry.


Where is it originally from?

The grey squirrel was introduced from England into Ireland at Castle Forbes, County Longford in 1911, where six pairs were released for aesthetic reasons. Sciurus carolinensis is originally from North America.


What can you do?

What can you do?
Visit the Invasive Species Ireland website to find out more and to report sitings.

©2007 Department of the Environment, Heritage and Local Government