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employed one man who killed 15,000 in one month. The Committee could come
to no satisfactory conclusion favourable to the adoption of Professor Loeffler’s
method of destroying Voles by means of bread saturated in a preparation of
mouse typhus, and other poisonous methods were considered too expensive. It
seems, therefore, that with all his scientific knowledge man is more or less
powerless to check these animal hordes when once they have gained a footing.
The abnormal increase of this species will doubtless occur again and again
in the great grazing lands of Southern Scotland, for so late as 1903 we hear , of
constant complaints of small local plagues in the Border counties. I f the Voles
remain there, a succession of mild winters will.be sure to produce y e t% another
plague.
A curious circumstance was related to me by a friend who was anxious to
witness the destruction caused by the mice in 1892 on a farm in Roxburgh. He
was told to repair to a certain open hillside above a lake which he had seen on
the previous day, and after walking for some time in what he supposed to be the
right direction he was mystified by not being able to find the lake in question.
After rambling about for some hours he discovered in front of him a great plain
of dried grass, and so perfectly flat that his curiosity was excited. Proceeding to
view the phenomenon, he suddenly found himself plunged into two feet of water.
He had in fact walked straight into the lake without knowing it. During the
night a wind had arisen and blown the whole of the grass cut by the Voles from
the hillside above, and this mass of yellow material floating on the surface of the
pool had completely hidden the waters.
The Field Vole has many natural enemies, and the ruthless and indiscriminate
slaughter of these is no doubt largely responsible for the alarming dimensions
which Vole plagues now assume. Weasels, stoats, and foxes are their mammalian
enemies,1 whilst in this country the white, tawny, long-eared and short-eared owls
are all known to prey on Voles. Rooks and crows also destroy numbers of
young ones as well as adults, and the kestrel feeds principally on Voles and mice.
Buzzards and kites are now so scarce that their attacks can hardly be said to
count.
The weasel is a great Vole hunter. I could hardly have credited it had I not
myself seen a full-grown weasel go down a Vole shaft in my garden with as much
ease as a ferret enters a rabbit-hole. His lithe body must have been able to turn
1 The Swiss naturalist Fatio includes the hedgehog amongst the enemies of the Vole, and certain observers have also
mentioned the mole as an occasional aggressor, but there is no proof that this is true.
at the bottom of the hole, for he soon reappeared and dived into another one,
which he also drew blank. I had always considered that weasels killed Field Voles
by scenting and taking them in the runs on the surface of the ground, so the fact
that they can also enter and attack them in their homes was something new to me.
Weasels constantly hunt the tunnels of Bank Voles, but the galleries are much
wider than those made by Field Voles. Weasels will kill far more than they can
devour, apparently out of sheer lust of blood.
A question asking him if he had ever seen a weasel kill a Vole was addressed
to David Glendinning, a shepherd, during the session of the Committee which
inquired into the Vole plague in Scotland in 1892, eliciting the following reply:
‘ Yes, about three weeks ago I came upon a small brown weasel which had killed
five in one of the sheep-drains. I followed it up and found it killing its sixth.
A week past, on Sunday morning, I came down a drain for 250 yards or so.
A weasel had been before me, and there were twenty-two dead Voles in the
bottom. I secured a specimen last night in order to show you the way a weasel
destroys a Vole. The blood is entirely drawn from behind the left ear. There is
not a bit of the Vole marked otherwise, except by the tooth-marks on the head.
All those I have seen were killed in the same way.’
Stoats undoubtedly kill a few Voles, but I think that their attacks on them
have been somewhat exaggerated, and doubt if they do any real good in thinning
the numbers. A stoat will always go for larger game when he can get it. Foxes
will kill large numbers and carry a mouthful at a time to their young ones, whilst
the most inveterate foe of the Field Vole in Scotland is the collie dog. I have
seen a collie .-stuff himself so full of Voles that he was sick, and then start hunting
and eating again as if nothing had happened. In the island of North Uist I have
seen collies hunting Field Voles all day long when not actually engaged in work.
Amongst birds the short-eared owl makes the Field Vole its favourite prey.
In North Uist I have seen two or three pairs of these birds beating about the
whole day catching Voles, and as I never molested them they would often come
and hunt close to me when I was shooting snipe. In the same island the
hen-harrier also preys largely on Voles. After every big irruption of Voles in
Scotland, and formerly in England, numbers of short-eared owls have appeared
and fed for weeks on the Voles: these birds should be strictly protected by law
at all seasons. The barn owl is also a most useful destroyer of Voles, as the
examination of owl pellets has shown to u s; and tawny and long-eared owls
doubtless kill a good many in the vicinity of the woods which they frequent.