Why are red squirrels so rare?
There are a number of reasons for the decline of the red squirrel over recent centuries, most of which are due to the introduction of the grey squirrel from North America in the early 1960s • The grey squirrel is a carrier of two viruses which are fatal to red squirrels – parapoxvirus (also known as squirrelpox) and the lesser known adenovirus. • Grey squirrels can survive in far higher densities than reds, have a more eclectic diet and are more aggressive, driving the indigenous Reds out of areas where they overlap • While grey squirrels are happy travelling on the ground, reds are far more arboreal and the destruction and thinning of the UK’s woodlands has made vast areas of the country unsuitable • Red squirrels were very numerous in the past and a pest in the 1700s. A brutal system of eradication throughout the early part of the nineteenth century hit the UK population hard and allowed grey squirrels space to get a foothold when they arrived.
