Musty Mustelids

Naturalists love them but gamekeepers hate them for their predation on game. I have seen five species (or their faecal calling cards) within a hundred yards of my home in Strathtay, and I suspect at least one more.

I have seen Otters in the River close by; stoats and weasels help to keep the rabbits out of my flower beds. On one occasion a large polecat calmly strolled up my drive in the middle of the day and, most beautiful of all, the pine martens leave their droppings on the lawn.

Pine martens, as we will see in a future exploration of the ‘weasel tribe’ in this column, are not uncommon now in Perthshire but being like most of the mustelidae largely nocturnal are rarely seen. I usually manage one or two sightings of this elusive mammal each year but one has to keep one’s eyes skinned for they have learned to avoid man like a plague. The suspect is mink, which I saw frequently in Warwickshire, but though I see suspicious tracks I have not seen in Tayside.

To gamekeepers they are all vermin. That is a word I dislike and medically I associate it with disease-carrying critters such as lice, scabies and unpleasant intestinal parasites. In fact, the word derives from the Latin vermes: a worm and was applied to anything worm-shaped from the human appendix and snakes, to the sinuously shaped weasel.

All the mustelidae are carnivores and so will eat small beasts, birds eggs as well as worms and many other invertebrates. Thus they earn the wrath of gamekeepers by destroying poults of grouse, pheasants and partridge. But they also kill enormous numbers of small rodents, so on balance they probably do more good than harm.

This underlies the problem facing the ecologist. Human beings tend to make value judgements about the creatures with whom we share our planet; some are good and should be encouraged; some are bad and should be persecuted out of existence. The trouble is, it is hard to find a living creature that is wholly good or wholly bad – though an exception might be the smallpox virus - and it is hard to find much that is lovely about the rat Rattus norvegicus.

But these living organisms are part of the balance of nature; if one drastically reduces their numbers some ecological imbalance occurs; the eradication of smallpox has been partly responsible for the explosion of the human population which is now threatening ecological disaster. It is difficult to argue in favour of the rat but, as it probably outdoes even Homo sapiens in its ability to survive and reproduce enormously, we could probably never discover what imbalance its extirpation would cause.

For at least a thousand years man has been wrecking the ecosystem by introduction, selective culling or breeding of flora and fauna of the planet in general and Scotland in particular.

In a change of direction after 100 bird species in this column I am turning to mammals and concentrating on families of Scottish beasts with particular attention to the ecological niches they live in, and their relationship with man. So I will start with details of the ecology of Otters, Badgers, Polecats, Stoats and Weasels as well as two species of martens (one of which, though it has never lived in Britain, was once believed to have done so.)

Unlike the denigrators of these species I like to see them, but they often stimulate controversy so I may irritate those with different views … but that is one of the functions of a columnist.

©Robin Hul