Squirrels can be seen on Norton Common all the year round They are not a difference species – they are just grey squirrels with a lot more black or dark brown hair in their pelage (fur).
The grey squirrel (Sciurus carolinensis) is not native to Britain. They were first introduced from the United States in the mid 19th century. The black ones are just grey squirrels with high levels of the black pigment ‘melanin’ in their hair. They are called ‘melanic grey squirrels’. Although generally rare across Britain, black squirrels are found in: Cambridgeshire, Bedfordshire and Hertfordshire.
In the autumn and winter, as the undergrowth dies down, these small deer are more noticeable. They are usually more active at dawn or dusk but, in recent years on The Common, they appear to be bolder and are often seen during the day. Muntjac were first introduced from China to Woburn Park in Bedfordshire in the early 20th century. Deliberate releases and escapes from Woburn, led to feral populations establishing all over the place, including Letchworth. They are russet brown in summer, grey brown in winter and are small, up to 52cm. Males have short antlers which can regrow. They feed on herbs, brambles, ivy, heather, coppice shoots, etc. and can live for 15 years or more. A common name for muntjac is "barking deer" after their repeated, loud bark when rutting and at other times. They can be heard several roads away – you may have heard them at any time of the day or year. They breed all year round. We don’t know how many live on Norton Common. They are usually seen in ones or twos, never in herds.Muntjac are the oldest known deer, appearing 15-35 million years ago, - remains have been found in Miocene deposits in France and Germany.