Introduction

One of our most popular and well loved mammals, the red squirrel Sciurus vulgaris has been a part of the Scottish fauna for thousands of years. It is thought to have arrived in Britain at the end of the last Ice Age, approximately 12,000 – 7,000 years ago, and has been present ever since.

However, the population has not always been stable and red squirrels are reported to have become extinct in some parts of Scotland following large scale deforestation in the 18th century. Populations were supplemented by the introduction of red squirrels from England and, possibly Scandinavia in the late 18th and early 19th centuries.

Scotland now contains the largest continuous population of red squirrels in Britain, supporting 121,000 (75%) of the estimated total of 161,000 animals. However, today’s native red squirrel faces a continued challenge from the North American grey squirrel, Sciurus carolinensis, which was first introduced to Britain in 1876.

To date, the grey squirrel has replaced the red squirrel throughout most of England and Wales, although the native species can still be found in north Cumbria and Northumberland and in small isolated pockets further south. Red squirrels are also found in Northern Ireland, although their range has also contracted noticeably since the introduction of grey squirrels there approximately 50 years ago. In Scotland, the grey squirrel was introduced in three places: Argyll (1892), Fife (1919) and Edinburgh (around 1919). It has since spread south into the Borders and north into Perthshire. Grey squirrels are now widespread in central and southern Scotland with isolated pockets in Aberdeen and Deeside. Their spread is likely to continue.