Project researching black squirrels launched
Researchers from Anglia Ruskin University have asked for the public's support in a project to measure the spread of the black squirrel within the UK.
Historically, squirrels in the UK were of the iconic red variety that remains prevalent in Europe and Eurasia. However, about 100 (North American) Eastern Grey squirrels were introduced to more than 30 sites across the UK and Ireland between 1876 and 1929, with dramatic consequences for the native population. While the grey squirrels are not affected by the so-called 'Grey Squirrel Pox' they carry, the red squirrels have been drastically affected and population numbers have crashed. It is estimated that there now are over two million grey squirrels in the UK, while no reliable numbers exist for the number of black squirrels.
Black squirrels are of the same species as the more numerous greys, but possess a melanosis mutation in the gene governing coat colouring that gives them their signature black coat. The first 'official' sighting of a black squirrel in the UK was in 1912. It appears that one small group that may have been from a single private menagerie in Bedfordshire were released into the wild and expanded. Their expansion since, in light of the fact that grey and black squirrels can interbreed, has been attributed to the consequences of the black squirrel colony joining up with population groups of greys. So far, black squirrels have been spotted in Bedfordshire, Cambridgeshire and Hertfordshire.
Commenting, Project Lead Researcher Dr Helen McRobie said “Although we know black squirrels are spreading, as yet we don't have evidence that they are living elsewhere in the British Isles. We want to understand if the blacks are, in fact, spreading faster than the greys,"
The team has also expressed the hope that they can build genetic profiles of both grey and black squirrels. At present, their major source of squirrel DNA is that which is harvested from roadkill.
"If there's anyone involved in culling or pest control - of either the black or the grey squirrels - it would be fantastic if I could take DNA samples from the squirrels they catch." Dr McRobie added.
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