CARNIVORA--FERRETS, STOATS, AND WEASELS.
The Mustelidae, or weasel family, is the most heterogeneous assemblage
of all the carnivorous group. Though differing much among themselves,
they possess certain important characters in common. One of the most
familiar is the presence of anal glands, situated beneath the root
of the tail, which contain a more or less noxious and evil-smelling
fluid. The three members of the family which have been introduced into
New Zealand belong to the genus _Putorius_, which receives its name
from the Latin word _putor_, a stench. The most notorious example is
the American species, the skunk, whose perfume is so strong that David
Harum records how a man who killed one went into the woods for a week
and “hated hisself.”
Of all intentional introductions to this country that of the animals
of this family is the most unfortunate and undesirable. The history of
the business is, to my mind, a depressing one, for it shows what people
are prepared to do to save their own pockets, whatever the effect
may be upon others. These animals have not done what was expected of
them--namely, suppressed the rabbits, or even kept them in check, but
they have exercised a most baneful influence on the bird-life of the
country. The characteristics of the three species are somewhat similar.
They have been called vermiform animals, for they have a singularly
worm-like appearance. The body is long, narrow, and cylindrical in
shape, while the legs are relatively extremely short. The neck is also
very long, and bears a small, flattened head; the eyes are small,
savage-looking, and glittering.
The ferret is closely allied to the polecat, but is a domesticated
variety, and is zoologically interesting, because it is a true-breeding
albino, having white fur and pink eyes. It originated in Africa, and
retains this characteristic of its warm origin: that it is unable to
endure great cold; hence if it goes wild in New Zealand it usually
survives only in warm and sheltered localities. It is from 12 in. to
15 in. long, and is a stouter animal than either of the others. Though
a semi-domesticated animal, it never shows the slightest affection for
its master, and has usually to be kept in confinement. My son, Dr.
Allan Thomson, tells me that about Kekerangu, in Marlborough, wild
ferrets are at present very numerous.
I have no record of the introduction of the true polecat (_Putorius
foetidus_) into these Islands; but some five or six years ago Mr.
Anderton, curator of the Portobello Marine Fish-hatchery, shot two
animals which were too large for stoats, being about 18 in. long. They
were not ferrets, in that they were brown-coloured. Unfortunately
he did not keep the bodies, their smell, for one thing, being so
offensive; so their specific character was not determined.
[Illustration:
[_J. Macdonald, photo._
FIG. 9.--THE FERRET.]
The stoat is about 1 ft. long and is somewhat distinctively coloured.
“In summer the upper parts vary from yellowish-brown to mahogany-brown,
while the underside is white tinged with sulphur-yellow, except on the
throat, which is pure white. The tail is tipped with black. The brown
upper and white under surfaces are separated by a perfectly distinct
line of demarcation, which extends from the snout to the root of the
tail, dipping down at the limbs, so as to include the outer surfaces
of the latter in the dark area. In winter, on the other hand, the
skin is--with the exception of the tip of the tail, which always
remains black--pure white, tinged here and there with sulphur-yellow.
Intermediate states between full winter dress and full summer dress are
often found.” In winter, when the fur is white, the animal is known
as the ermine, and white stoats are well known in winter in the South
Island. The favourite food of the stoat consists of rats and mice,
but it is fond of birds, and thus is a danger in a poultry-yard. It
occasionally attacks lambs. These creatures seem often to kill for the
mere sake of killing. In my boyhood days I at one time kept a large
number of rabbits in an enclosure. One night a stoat got in and killed
the whole lot--over a dozen--and left each with a hole in the back of
its head. These animals are fairly abundant over New Zealand at the
present time.
[Illustration:
[_J. Macdonald, photo._
FIG. 10.--THE STOAT.]
One is frequently asked what is the difference between a stoat and a
weasel. According to one authority, the one “is stoatally different
from the other, and weasely distinguished.” But this does not help
us much. The weasel “in length, from snout to root of tail, does
not exceed 8 in. The tail is about 2 in. long. The fur is light
reddish-brown above, and white below.” The size and black-tipped tail
best distinguish the stoat. The weasel is a good climber, and makes use
of its skill in this accomplishment to prey upon birds, their eggs and
young. Rats and mice are its favourite food.
[Illustration:
[_J. Macdonald, photo._
FIG. 11.--THE WEASEL.]
The history of the introduction of these vermin into this country is
characteristic of the acclimatization methods of the past. Ferrets
have been introduced from early times by dealers in birds and animals.
The first authentic record is that of the Canterbury Acclimatization
Society, which received five in 1867. They were apparently not
liberated, nor were subsequent introductions for some time. When
rabbits began to increase to an alarming extent various suggestions
were made as to the importation of what was called “the natural enemy.”
The fox is the real natural enemy of the rabbit, but this was too risky
a proposal to be made. The Victorian Government had already allowed
some idiots to introduce foxes into that country in order to allow them
the pleasures of fox-hunting, and the result has not been encouraging.
One well-known public man in New Zealand proposed to introduce Arctic
foxes “because their fur would be so valuable.” When it was pointed
out to him that they would probably prefer lamb to rabbit, he replied
that, as they did not know anything about lambs in their native haunts,
it was improbable that they would take to eating them in New Zealand.
Fortunately his proposal was not given effect to. Meanwhile sheepowners
brought pressure to bear on the Government, and as a result steps were
taken to obtain ferrets. Numbers of these were introduced in 1882, and
in the following year Mr. Bailey, Chief Rabbit Inspector, recommended
the introduction of stoats and weasels. To show the scale on which
these recommendations were carried out, I summarize from Mr. Bailey’s
reports as follows:--
(_a._) In July, 1883, it is stated that since March, 1882 (fifteen
months), the Agent-General had made thirty-two shipments of ferrets
from London, numbering altogether 1,217 animals. Of these, only 178
were landed, at a cost of £953. Of 241 purchased in Melbourne, 198
were landed, at a cost of £224. Thus the total number landed was 376,
and the cost £1,177, or £3 2s. 7d. per head. The natural increase was
122, but 157 died of distemper. At this period it would seem as if
the Government kept a perfect menagerie of these animals. In the same
year a substantial bonus was offered to any one who would introduce a
certain number of stoats or weasels in a healthy condition.
(_b._) In 1884 he reports “nearly 4,000 ferrets were turned out; 3,041
in Marlborough alone, and about 400 on Crown land in Otago.” The
rest appear to have been sold to private individuals. It is evident
that there was no study of the suitability of a semi-domesticated
subtropical animal becoming acclimatized in this country, and, as a
matter of fact, the ferret has not gone wild in the South Island to any
great extent. Mr. Bailey also stated in this report that “an agent has
been sent Home to procure stoats and weasels.” Mr. Rich, of Palmerston,
imported some of these latter in a sailing-vessel, but how many I
cannot learn.
(_c._) In 1885 two lots of stoats and weasels were received from
London--viz., 183 weasels (out of 202 shipped) and 55 stoats (out of
60). Of these, 67 weasels were released at Lake Wanaka on a peninsula
of 8,000 acres, on which they reduced the rabbits, but by no means
exterminated them; 28 weasels were liberated at Lake Wakatipu; 15
weasels near the Waiau River, in Southland; and 8 stoats at Ashburton.
The rest were sold at Wellington, Christchurch, and Dunedin.
(_d._) In 1886 the Government introduced two lots. Of these, 82 stoats
and 126 weasels were distributed in about equal lots to the Wilkin
River, the Makarora, at the head of Lake Ohau, and on the Waitaki; and
32 stoats and 116 weasels were distributed between Marlborough and West
Wairarapa. A private shipment of 55 stoats and 167 weasels was also
received for Riddiford’s station in West Wairarapa. The localities
selected for these animals were those in which rabbits were most
abundant. Mr. Bailey also reported that “ferrets were turned out by
thousands,” but the success was only partial.
In the same year a meeting was held at Masterton to consider the
administration of the Rabbit Act, and the best means of dealing with
the pest. One of the resolutions carried was, “That the introduction of
ferrets, stoats, and weasels in large numbers is in the opinion of this
meeting the only means by which the rabbit pest can be successfully put
an end to, and that every owner of land infested with rabbits should
either turn out ferrets in proportion to his acreage or contribute to
a fund for the breeding and purchase of ferrets, stoats, and weasels
to be turned out in the district. That the landowners present form
themselves into an association for the purpose of providing the
natural enemies.” An association was accordingly formed with this
object in view, large sums of money were subscribed, and hundreds
of stoats and weasels were introduced into the district. Several of
the acclimatization societies took strong exception to the action of
the Government and of the sheepowners directly concerned; but as the
societies were themselves directly responsible for the rabbits to a
large extent their protests were ineffectual.
These animals have not exterminated the rabbits; they do not even
keep them in check in most parts. They have, however, helped in the
practical extermination over wide areas of many species of indigenous
birds, for they have penetrated into quite unsettled and unbroken parts
of the country, where apparently they feed on the avifauna.
Every one who has had any experience of these vermin has his own view
as to their usefulness or otherwise, but it is seldom that careful
observers put their experiences down on paper. I have collected some
evidence on this subject, and give here a few of the observations which
have been recorded.
Mr. George Mueller, Chief Surveyor of Westland, in his report on the
“Reconnaissance Survey of the Headwaters of the Okuru, Actor, and Burke
Rivers” (Reports N.Z. Survey Department for 1889-90, p. 50), says,
“Several weasels and ferrets were caught and killed at the Okuru and
Waiatoto Settlements, within about a mile from the sea-coast.... No
rabbits were met with until near the Actor, nineteen miles from the
coast, and they were only seen in numbers at the very headwaters of
the Okuru.... Meanwhile the kakapos, kiwis, and blue ducks have nearly
disappeared from the district.”
Mr. Richard Henry, writing from Lake Te Anau in September, 1890, says,
“I have known the ferrets to take young paradise ducks out of a clutch
often in 1888, and last year the same pair of ducks reared only two
young ones; but away from the lake I have seen larger families. I
found two black teal ducks killed by a ferret, though it is seldom any
of their work is seen, for they always drag their prey under cover.
The black teal are getting scarce.” Mr. Henry adds, “I think very few
ferrets at liberty survive the winter for want of food.” My own opinion
is that they cannot endure the cold.
Mr. Richard Norman, Albert Town, writing in the _Otago Witness_ of the
2nd October, 1890, says, “I think that Mr. E. H. Wilmot’s experience in
the Hollyford Valley, as recorded in the _Witness_ a year or two ago,
conclusively proves that the imported vermin kill the native wingless
birds. He encountered there a ferret-warren, and the weka, kiwi, and
kakapo were almost exterminated. In the Makarora Valley these used to
be plentiful, but since the advent of the stoats and weasels they are
very rare, and rabbiting tallies have not depreciated.”
Mr. Charles J. Peters, of Mount Somers, writes about these animals
(1916): “Since the stoats and weasels became fairly numerous the
rabbits have increased 100 per cent. and more. I have found weasels’
nests both in heaps of fencing-material and also in rabbit-burrows.
These nests have always been made of skylarks’ feathers. I have also
found parts of young hares at weasels’ camps, but never a sign of a
rabbit.”
Mr. Yarborough, of Kohukohu (Hokianga), states that stoats and weasels
do not seem to be so numerous now (1916) as they were some few years
ago. At that time a great number of these intrepid little animals
appeared on the eastern side of Hokianga Estuary, and were occasionally
observed swimming across the river, which is about a mile wide. For the
last year or more they have neither been seen nor heard of. The same
observation has been made of the occurrence of these animals on the
peninsula on which the Portobello Marine Fish-hatchery stands. Three or
four years ago they were very abundant, but recently there are few to
be seen.
In Taranaki a correspondent informed me last year that either stoats or
weasels destroyed a litter of nine sucking-pigs in one night. Another
informant states that “at Lee Stream, in the Taieri district, I saw
a rabbit paralysed with fright and uttering squeals of terror, and
on looking for the cause observed a stoat fully 10 ft. away walking
deliberately towards its victim. The rabbit was killed by one bite
on the neck. A few weeks ago a lady informed me that she had seen a
somewhat similar occurrence at Brighton, but in this case the rabbit
struggled to the lady for protection, and fell trembling at her feet,
while the stoat disappeared.”
A few years ago stoats were fairly common in the suburbs of Wellington,
and made great depredations amongst poultry, entering the fowlhouses at
night. My son describes seeing a couple playing in a vacant section at
Hataitai, and taking not the slightest notice of passers-by.