American Falls press. [volume] (American Falls, Idaho) 1907-1937, 1914-12-10
KEEPING DOWN FEVER
BY KEEPING DUCKS

Malaria and yellow fever are both
spread by mosquitoes. The only prob
lem before humanity in getting rid
of the two fevers is to get rid of the
insects that carry the fever germs.
DR.. Samuel G.. Dixon, state health COM
missioner of Pennsylvania, writing for
the Journal Of the American Medical
Association, advocates keeping ducks
to keep down the two diseases.
1t used to be thought, and 1t is still q
common delusion, that malaria es-
pecially was caught" by inhaling bad
air. 1t has been proven eyond doubt
that the only way the germ either of
1t or yellow fever can be communicate
ed is through the bite of the mosquito.
When the mosquito takes up the fever
germs in marshes and low-lying places
the germ itself has no effect upon the
insect, but when 1t inserts its cutting
and sucking apparatus into man, the
hacilli make their way into the hn
man blood in practically the same way
as though injected by a hypodermic
needle
DR.. Dixon points out that the duck
has the widest geographical range Of
any bird. 1t is an omnivorous eater
of the mosquitoes young. Besides its
appetite its movement through the
water creates water motions which
drown the mosquito young which,
just before they hatch into the full
f1edged pests, turn from wrigglers in
to pupae, which are air breathers.
These pupae float upon the surface of
the water during the brief period of
metamorphosis into the winged insect.
They need to breathe. Any medium
which submerges them, browns them.
Describing his experiments on
ducks Is mosquito destroyers, DR..
Dixon says:
after trying the ability of fish to
devour larvae and pupae of mosqui-
toes, with varied success, l built two
dams near together on the same
stream, so that each would have the
same environment for the breeding
of mosquitoes. Each covered nearly
1,400 square feet. In one, twenty mall
lard ducks were permitted to feed,
while the other was entirely protect
ed from water fowl but we'll stocked
with gold fish.
1.-THE pool in which the ducks fed
was for several months entirely free
from mosquitoes, while the pond pro-
tected from ducks and stocked with
fish was swarming with young insects
in different cycles of life.
I'm the infested pond-the n that
had been stocked with gold fish-ten
well-fed mallard ducks were her adj
mitted, and as they entered the pond
they were first attracted by the tad
poles. They, however, soon recognized
the presence of the young Of the mos
quito, both in the wriggier and larvae
stage, and Immediately turned their
attention to these, ravenously devour-
ing them in preference to any other
foodstuff present. At the end Of TWEEN
ty-four hours no pupae survived The
motion Of the water, made by the
ducks, of course drowned some OF the
insects-what proportion cannot be es-
timated.
For some years I have been using
ducks to keep down mosquitoes In
swamps that would have been very ex-
pensive to drain, but I ! never fully ap-
p~reciated the high degree of efficiency
OF the duck as a destroyer of mosquf-
to life until the foregoing test was
made.
"Mr. william lockwood, Of Boston,
an artist who made a hobby Of raising
aquatic fowl. also expresses an opinion
that the spoon-billed duck is parti-
cularly adapted to the destruction OF
mosquito larvae resting on the sur
face
Ducks can be used In ponds.
swamps, both open and in jungles, and
q be driven from place 10 place Not