Animal activists have once again grabbed the headlines with the release of mink in England.
Many people have been caught up in the hysteria surrounding hundreds of these little animals being at liberty in the countryside.
It should be remembered that mink do not occur naturally in this country because of the formation of the Channel after the last glaciation preventing immigration by European mink from the continent.
American mink were introduced primarily by returning servicemen after the World Wars using their fratuities to set up fur farms.
They solemnly promised that no animals would ever escape, which, of course, they promptly did.
American mink are a problem not just in Britain, but also in countries such as Iceland, Argentina, Estonia and Belarus.
After a while the gross overcrowding subsides following an escape on the scale we have witnessed in 1998, as animals are recaptured, killed or wander away.
In the British countryside they seem to achieve the kind of balance in the eco system without appearing to cause much harm, except to one other creature in particular - the water vole.
However, it looks increasingly likely that this attractive little rodent is ultimately doomed.
It just has no protection from a creature which can both follow it down its burrows and outswim it.

The news that up to 10,000 mink may need to be culled by conservationists anxious to save the ground-nesting sea birds of the Outer Hebrides might raise a few eyebrows.
The aim is the total extermination of introduced mink and I hope that, on this occasion, the conservationists succeed.
Over the next few decades thousands of birds will owe their lives to their efforts if they can remove this predator once and for all, but it is a tall order.
The Outer Hebrides is a world-class habitat for all sorts of rare birds which predominantly nest on the ground. They are all at risk of being wiped out.
Eventual success is always a possibility. In Norway and Sweden, they have resigned themselves to killing thousands of mink each year and still there are more filling their places.

These very unwelcome interlopers first appeared in 1982, travelling east along the banks of the North Calder River. All the examples we have observed have been of the chocolate brown, wild type. Sometimes we can go for months without seeing one, but then more dead waterfowl tell their own dismal story, so much so that we have now stopped using the riverside paddocks for any sort of vulnerable birds.

Despite their depredations, their presence can have its lighter moments. In 1985, one of the volunteers, a very strong and enthusiastic young man, greeted the Director as he drove into the Zoo, by triumphantly emerging from behind a low beech hedge clasping a wriggling creature with both hands:
"Mr O'Grady, I've caught the escaped ferret from the Education Department."
"But we haven't lost a ferret," he replied, simultaneously noticing hands and arms dripping with blood!