27 JULY 1944, Page 11

Astraea Re dux It is pleasant to have made sure

that red squirrels are coming back, at any rate in the county of Herts. They have been watched by a number of observers, for example, in and by woods near the Great North Road. Why they diminished in number, to the point of total disappearance in many districts, no one knows for a certainty. Even where they were re-introduced—as at Whipsnade and in North Devon—they were seen no more after two or three years. Nearly all the smaller mammals suffer sudden falls after rising to a hotchpotch of population ; and the cause is generally disease. It is not improbable that the grey squirrel banishes the red ; but there is no evidence that it destroys it. In the same shire where the red is now flourishing again have been seen of late several specimens of the black squirrel, which local naturalists unite in regarding as a melanistic freak of the grey squirrel. Is it? I am told that a number of black squirrels were introduced some years ago in Bedfordshire, and these were presumably an established variety, not a mere sport. Among other mammals that were thought to be growing extinct but have revived is the polecat, including no small proportion of a reddish variety.