Country diary: your eyes do not deceive you – this is a black squirrel

Above my head, two squirrels race through the sycamores. They are not the same colour. The pursuer is a flash of grizzled pewter, russet stains around its flanks and eyes; the other, a streak of inky darkness. Pewter – black – pewter – black. My eyes struggle to follow their acrobatics until they call a truce. For a moment they are visible, shelling acorns in the crook of a thick ivy stem. Then the black squirrel pauses and winks out of existence, its dark fur swallowed by the shadows.

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?

I found out that black squirrels – a melanistic form of the grey squirrel – had been in the area for decades. Thought to have escaped from a private menagerie in the early 20th century, the UK population is now estimated at 25,000, based mainly in Hertfordshire, Cambridgeshire and Bedfordshire.

Letchworth Garden City, with its broad tree-lined streets and green parks, has become a stronghold for these charismatic rodents. Over the years, they have acquired a quirky celebrity status, lending their name to a dark ale, a credit union and the first pub to serve alcohol in this Quaker-influenced town.

I rarely walk on Norton Common without learning a little more about squirrel business. Last week it was a lesson in design, when what I thought was a burr on an oak uncurled a long black tail. Black on back, legs and head, this squirrel had a ginger belly and a mossy green beard that turned out to be a mouthful of lining for its drey, high up in the fork of a silver birch.

Often, like today, the squirrels are engaged in a mating chase, or perhaps they are establishing dominance. Whatever their purpose, for these two, snack time is over. With a shiver in the shadows, the black squirrel reappears and they’re off, racing into the sycamore canopy in a spiralling game of follow-my-leader.

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