INTRODUCED SPECIES THAT HAVE BECOME PESTS
The man who successfully transplants or "introduces" into a new habitat
any persistent species of living thing, assumes a very grave
responsibility. Every introduced species is doubtful gravel until panned
out. The enormous losses that have been inflicted upon the world through
the perpetuation of follies with wild vertebrates and insects would, if
added together, be enough to purchase a principality. The most
aggravating feature of these follies in transplantation is that never
yet have they been made severely punishable. We are just as careless and
easy-going on this point as we were about the government of the
Yellowstone Park in the days when Howell and other poachers destroyed
our first national bison herd, and when caught red-handed--as Howell
was, skinning seven Park bison cows,--_could not be punished for it,
because there was no penalty prescribed by any law_.
To-day, there is a way in which any revengeful person could inflict
enormous damage on the entire South, at no cost to himself, involve
those states in enormous losses and the expenditure of vast sums of
money, yet go absolutely unpunished!
THE GYPSY MOTH is a case in point. This winged calamity was imported at
Maiden, Massachusetts, near Boston, by a French entomologist, Mr.
Leopold Trouvelot, in 1868 or '69. History records the fact that the man
of science did not purposely set free the pest. He was endeavoring with
live specimens to find a moth that would produce a cocoon of commercial
value to America; and a sudden gust of wind blew out of his study,
through an open window, his living and breeding specimens of the gypsy
moth. The moth itself is not bad to look at, but its larvae is a great,
overgrown brute, with an appetite like a hog. Immediately Mr. Trouvelot
sought to recover his specimens, and when he failed to find them all.
like a man of real honor, he notified the State authorities of the
accident. Every effort was made to recover all the specimens, but enough
escaped to produce progeny that soon became a scourge to the trees of
Massachusetts. The method of the big, nasty-looking mottled-brown
caterpillar was very simple. It devoured the entire foliage of every
tree that grew in its sphere of influence.
The gypsy moth spread with alarming rapidity and persistence. In course
of time the state authorities of Massachuestts were forced to begin a
relentless war upon it, by poisonous sprays and by fire. It was awful!
Up to this date (1912) the New England states and the United States
Government service have expended in fighting this pest about $7,680,000!
The spread of this pest has been retarded, but the gypsy moth never
will be wholly stamped out. To-day it exists in Rhode Island,
Connecticut and New Hampshire, and it is due to reach New York at an
early date. It is steadily spreading in three directions from Boston,
its original point of departure, and when it strikes the State of New
York, we, too, will begin to pay dearly for the Trouvclot experiment. It
is said that General S.C. Lawrence, of Medford, Massachusetts, has spent
$75,000 in trying to protect his trees from the ravages of this scourge.
THE RABBIT PLAGUE IN AUSTRALIA AND NEW ZEALAND.--The rabbit curse upon
Australia and New Zealand is so well known as to require little comment.
In this case the introduction was deliberate. In the days when the sheep
industry was most prosperous, a patriotic gentleman conceived the idea
that the introduction of the rabbit, and its establishment as a wild
animal, would be a good thing. He reasoned that it would furnish a good
food supply, that it would furnish sport, and being unable to harm any
other creature of flesh and blood it was therefore harmless.
Accordingly, three pairs of rabbits were imported and set free.
In a short time, the immense number of rabbits that began to overrun the
country furnished food for reflection, as well as for the table. A very
simple calculation brought out the startling information that, under
perfectly favorable conditions, a single pair of rabbits could in three
years' time produce progeny amounting to 13,718,000 individuals. Ever
since that time, in discussing the rabbits of Australia it has been
necessary to speak in millions.
"The inhabitants of the colony," says Dr. Richard Lydekker, "soon found
that the rabbits were a plague, for they devoured the grass, which was
needed for the sheep, the bark of trees, and every kind of fruit and
vegetable, until the prospects of the colony became a very serious
matter, and ruin seemed inevitable. In New South Wales upwards of
15,000,000 rabbits skins have been exported in a single year; while in
thirteen years ending with 1889 no less than 39,000,000 were accounted
for in Victoria alone.
"To prevent the increase of these rodents, the introduction of weasels,
stoats, mongooses, etc., has been tried; but it has been found that
those carnivores neglected the rabbits and took to feeding on poultry,
and thus became as great a nuisance as the animals they were intended to
destroy. The attempt to kill them off by the introduction of an epidemic
disease has also failed. In order to protect such portions of the
country as are still free from rabbits, fences of wire netting have been
erected; one of these fences erected by the Government of Victoria
extending for a distance of upwards of one hundred and fifty
geographical miles. In New Zealand, where the rabbit has been introduced
little more than twenty years, its increase has been so enormous, and
the destruction it inflicts so great, that in some districts it has
actually been a question whether the colonists should not vacate the
country rather than attempt to fight against the plague. The average
number of rabbit skins exported from New Zealand is now twelve
millions."--(Royal Natural History.)
THE FOX PEST IN AUSTRALIA.--And now unfortunate Australia has a new
pest, also acquired by importation of an alien species. It is the
European fox (_Vulpes vulpes_). The only redeeming feature about this
fresh calamity is found in the fact that the species was not
deliberately introduced into Australia for the benefit of the local
fauna. Mr. O.W. Rosenhain, of Melbourne, informs me (1912) that about
thirty years ago the Hunt Club brought to Australia about twenty foxes,
for the promotion of the noble sport of fox hunting. In some untoward
manner, the most of those animals escaped. They survived, multiplied,
and have provided New South Wales, Victoria and South Australia with a
fox pest of the first rank.
The destruction of wild bird life and poultry has become so serious that
Australia now is making vigorous efforts to exterminate the pest. The
government pays ten shillings bounty on fox scalps, besides which each
prime fox skin is worth from four to five dollars. It is hoped that
these combined values will eliminate the fox pest.
Regarding foxes in Australia, Mr. W.H.D. Le Souef has this to say in his
extremely interesting and valuable book, "Wild Life in Australia," page
146:
"We found that foxes were unfortunately plentiful in this district, and
in a hollow log that served to shelter some cubs were noticed the
remains of ducks, fowls, rabbits, lambs, bandicoots and snakes; so they
evidently vary their fare, snakes even not coming amiss. They also sneak
on wild ducks that are nesting by the edge of the water among the rushes
and tussocky grass, and catch quail also, especially sitting birds.
_These animals are, and always will be, a great source of trouble in the
thickly timbered country and stony ranges, and will gradually, like the
rabbit, extend all over Australia_. They are evidently not contented
with ground game only, as Mr. A.F. Kelly, of Barwonleigh, in Victoria,
states: "When riding past a bull-oak tree about twenty-five feet high,
with either a magpie's or crow's nest on top. I noticed the nest looked
very bulky, and had something red in it. On going nearer I saw a large
fox coiled up in it!"
THE MONGOOSE.--Circumstances alter cases, and a change of environment
sometimes works marvelous changes in the character of an animal species.
Now, _why_ should not the gray Indian mongoose (formerly called the
ichneumon, _(Herpestes griscus_)) destroy poultry in India, as it does
elsewhere? There is poultry in plenty to be destroyed, but
"Rikki-Tikki-Tavi" elects to specialize on the killing of rats, and
cobras, and other snakes.
In his own sphere of influence,--India and the orient,--the mongoose is
a fairly decent citizen, and he fits into the time-worn economy of that
region. As a destroyer of the thrice-anathema domestic rat, he has no
equal in the domain of flesh and blood. His temper is so fierce that one
"pet" mongoose has been known to kill a full grown male giant bustard,
and put a greyhound to flight.
In an evil moment (1872) Mr. W.B. Espeut conceived the idea that it
would be a good thing to introduce mongooses to the rats of Barbadoes
and Jamaica that were pestering the cane-fields to an annoying extent.
It was done. The mongooses attacked the rats, cleaned them out,
multiplied, and then looked about for more worlds to conquer. Snakes and
lizards were few; but they cheerfully killed and devoured all there
were. Then, being continuously hungry, they attacked the wild birds and
poultry, indiscriminately, and with their usual vigor. I have been told
that in Barbadoes "they cleaned out every living thing that they could
catch and kill, and then they attacked the sugar-cane." The last count
in the indictment may seem hard to believe; but it is a fact that the
Indian mongoose often resorts to fruit and vegetable food.
In Jamaica, at the end of the rat-killing period, the planters joyfully
estimated that the labors of Herpestes had saved between 500,000 pounds
and 750,000 pounds to the industries of that island. That was before the
slaughter of wild birds and poultry began. I am told that up to date the
damage done by the mongoose far exceeds the value of the benefit it once
conferred, but the total has not been computed.
Up to this date, the mongoose has invaded and become a destructive pest
in Barbadoes, Jamaica, Cuba, St. Vincent, St. Lucia, Trinidad, Nevis,
Fiji and all the larger islands of the Hawaiian group. It would require
many pages to contain a full account of each introduction, awakening,
reckoning of damages and payment of bounties for destruction that the
fiendish mongoose has wrought out wherever it has been introduced. The
progress of the pest is everywhere the same,--sweeping destruction of
rats, snakes, wild birds, small mammals, and finally poultry and
vegetables.
Every country that now is without the mongoose will do well to shut and
guard diligently all the doors by which it might be introduced.
Throughout its range in the western hemisphere, the mongoose is a pest;
and the Biological Survey of the Department of Agriculture has done well
in securing the enactment of a law peremptorily prohibiting the
importation of any animals of that species into the United States or any
of its colonies. The fierce temper, indomitable courage and vaulting
appetite of the mongoose would make its actual introduction in any of
the warm portions of the United States a horrible calamity. In the
southern states, and all along the Pacific slope clear up to Seattle, it
could live, thrive and multiply; and the slaughter that it could and
would inflict upon our wild birds generally, especially all those that
nest and live on the ground, saying nothing of the slaughter of poultry,
would drive the American people crazy.
Fancy an animal with the murderous ferocity of a mink, the agility of a
squirrel, the penetration of a ferret and the cunning of a rat,
infesting the thickets and barnyards of this country. The mongoose can
live wherever a rat can live, provided it can get a fair amount of
animal food. Not for $1,000,000 could any one of the southern or Pacific
states afford to have a pair of these little gray fiends imported and
set free. If such a calamity ever occurs, all wheels should stop, and
every habitant should turn out and hunt for the animals until they are
found and pulverized. No matter if it should require a thousand men and
$100,000, _find them!_ If not found, the cost to the state will soon be
a million a year, with no ending.
In spite of the vigilance of our custom house officers, every now and
then a Hindoo from some foreign vessel sneaks into the country with a
pet mongoose (and they do make great pets!) inside his shirt, or in the
bottom of a bag of clothing. Of course, whenever the Department of
Agriculture discovers any of these surreptitious animals, they are at
once confiscated, and either killed or sent to a public zoological park
for safe-keeping. In New York, the director of the Zoological Park is so
genuinely concerned about the possibility of the escape of a female
mongoose that he has issued two standing orders: All live mongooses
offered to us shall at once be purchased, and every female animal shall
immediately be chloroformed.
If _Herpestes griseus_ ever breaks loose in the United States, the crime
shall not justly be chargeable to us.
THE ENGLISH SPARROW.--In the United States, the English sparrow is a
national sorrow, almost too great to be endured. It is a bird of plain
plumage, low tastes, impudent disposition and persistent fertility.
Continually does it crowd out its betters, or pugnaciously drive them
away, and except on very rare occasions it eats neither insects nor weed
seeds. It has no song, and in habits it is a bird of the street and the
gutter. There is not one good reason why it should exist in this
country. If it were out of the way, our native insect-eaters of song and
beauty could return to our lawns and orchards. The English sparrow is a
nuisance and a pest, and if it could be returned to the land of its
nativity we would gain much.
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