The future is looking black for grey squirrels as numbers of darker variety soars in UK
By Tamara Cohen
Last updated at 1:55 AM on 31st January 2012
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After almost wiping out its red cousins in the UK, it seems the grey squirrel is getting a taste of its own medicine.
The black squirrel population is soaring and experts say it could eventually be the dominant variety.
There are now believed to be at least 25,000 – mostly in East Anglia – but isolated sightings have been recorded elsewhere.
A black squirrel in the UK: The squirrels were introduced in 1912 - scientists now aim to find out how far they have spread in the past 100 years
The spread of the black variant is the biggest change in squirrel demographics since the red population was devastated 50 years ago.
The grey squirrel was able to displace the native red because it is larger and better able to compete for food. It also infected the reds with a disease.
Once in the millions, red squirrel numbers have declined to just 120,000 in the UK.
The English population, found in isolated pockets in the North, East Anglia and the Isle of Wight, is down to 25,000 – the same as the black squirrel but about to be overtaken.
Black squirrel feeding: Scientists believe that the squirrels have spread around 50 miles in 100 years - a contrast to grey squirrels, which now number two million in the British isles
The black squirrel is actually the same native North American species as the grey but its colour is the result of a genetic mutation.
Scientists are not sure why the black variety is proving more successful. Research will focus on whether it is fitter or more aggressive.
Around 100 grey squirrels were introduced into Britain in the 1870s as an exotic pet. There are now two million. In the 1880s, around a dozen black squirrels escaped from a private zoo in Woburn, Bedfordshire.
The first one spotted in the wild was on the outskirts of Letchworth in Hertfordshire in 1912.
They compete with the greys for food and, when the two varieties mate, the black gene is dominant. Marina Pacheco, of the Mammal Society, said: ‘All of the grey squirrels could be black in a few decades.’
Scientists at Anglia Ruskin University have called on the public to report sightings to the website www.blacksquirrel project.org
Geneticist Helen McRobbie said: ‘Numbers have risen steadily over the years and they have been spotted in Cambridgeshire and Bedfordshire.
‘But we don’t have evidence that they are living elsewhere in the British Isles.
‘Therefore it would be great if as many people as possible can submit their sightings.’
Read more: http://www.dailymail.co.uk/sciencetech/article-2093826/Nationwide-hunt-Britains-rare-black-squirrel-100-years-introduced.html#ixzz1l1jset1k
1 comment:
The unassuming Red would never have had to retreat to avoid decimation by the diease carrying and more aggressive greys and dominant black variety if its natural habitat had not been utterly destroyed (other than a few humble patches of native woodland). The squirrel is the land and the land is the squirrel.
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