>"Letchworth Garden City, Hertfordshire: There are about 25,000 of this melanistic form of the grey squirrel in the UK, and here they are local celebrities"

I’m not surprised to see a black squirrel on Norton Common this morning, but it was a different story 20 years ago when I looked up from digging the veg beds to find a jet-black apparition eyeing me from a neighbour’s fence. As a newcomer to the county, I was dumbfounded. Was this a figment of my imagination? And where was the nearest optician?