Britain’s little known fourth variety of squirrel

First it was the red and the grey squirrel, and then the black. Now scientists have recorded a fourth type of squirrel living in the UK – a brunette variety.
First it was just the red squirrel, then the grey – and then a third, the little-known black variety, was observed. Now scientists have recorded a fourth type of squirrel living in the UK: a “brunette”. The creature’s existence has come to light following a nationwide research project, launched earlier this year, which asked the public to report sightings of squirrels. The brunettes, also known as “black-reds”, are dark brown or black in colour but have the body shape of a red squirrel, with its distinctive tufty ears. They may have white markings, particularly on their stomachs.
Their discovery makes them the rarest of all the UK’s squirrel varieties, with researchers unsure how many there may be. While populations of brunettes are established on the Continent, the researchers believe this is the first time they have been recorded in Britain.
The brunettes are a subtype of Britain’s native red squirrel, Sciurus vulgaris, which is now confined to small areas with only an estimated 120,000 remaining.
In a similar way, the black squirrel is a subtype of the grey, Sciurus carolinensis, which has spread across Britain since being introduced from North America in the 1870s. There are estimated to be up to more than 2.5 million greys and 25,000 blacks in the UK.
Both dark subtypes, the brunette and the black, have arisen through genetic mutations. Brunettes can interbreed with reds, just as blacks can with greys.
Anglia Ruskin University’s “Black Squirrel Project” was set up to track the spread of black squirrels across the country. Earlier this year the researchers asked the public to let them know of sightings and have had 4,000 reports.
However, the team concluded that some of sightings were not in fact of the black variety, but of the new kind, the brunette.
Helen McRobie, from the project, said populations of black-reds had been recorded in Italy, Germany, France and Spain, but were not previously known to exist in the UK.
“We now have a fourth category, it seems,” she added. “I didn’t know we had them here, but if people are seeing ‘black’ squirrels in areas where there are lots of red squirrels, we can now assume it is a black-red – rather than a black one.
“I knew about them in Europe, but not in the UK. It has been new to me. I am definitely sure now that they are here.”
Sightings of brunettes were recorded in several of the areas in which reds can still be found – in Scotland, Cumbria, Merseyside and the Isle of Wight.
Since they are not aware of any reported releases of black-reds, the researchers now believe the black-reds are native to Britain, and must have been living alongside the reds for thousands of years. The study, which is ongoing, has indicated a clear trend that blacks have spread from their original location in a north easterly direction. It is thought this could be due to the prevailing south-westerly wind.
Numbers of red squirrels have crashed in the last 100 years as greys have spread disease and taken over their habitats. The experts say that red-blacks only comprise a tiny proportion of the red population.