The Calumet news. [volume] (Calumet, Mich.) 1907-1938, 1911-10-19
SKATERS BELIEF
OF FISHERMEN
TESTS SHOW THAT TROUT AND
OTHER FISH PAY LITTLE
ATTENTION TO NOISE
ABOVE WATER.

That trout fishermen hav0soyer osti-
mated the Importance of Keeping quiet
while fishing seems to be the natural
Inference to be drawn from bulletin
just issued by the United States bureau
of fisheries. discussing the effect OF
sounds upon fishes. The tests onwhioh
the observations in the pamphlet are
based were made particularly TO de-
termine whether the rapidly increasing
number Of motor boats is in any way
responsible for the depletion of many
streams and lakes of fish,
Experiments were conducted with
different kinds of fish, and gun shots
as well as motor boats were used in the
tests. 1t was found that the sounds
produced by motor boats are extremely
faint under water and have little influ-
cnce on the movements and feeding of
fishes. Such influence as they do have
Is temporary and very much restricted
in local extent. 1t was found that sin
gle explosive sounds, like the report of
a gun, may startle fish and cause them
TO cease feeding. but that these re-
sponses are also temporary and local.
on this subject the bulletin says:
"The noises produced by motor boats
have only a slight and local influence
on fishes, not only because the noises
that really get into the water are very
faint, but probably because they reach
the fish in the most favorable way for
H.. ,.I,.
have experimental with the effects of
sound on fishes have been struck with
the fact that after fish has respond
ed once or twice To a given sound. ii
often ceases to respond To further
stimula ton for some considerable time,
and i'm experiments of this kind it is
usual to allow relatively long intervals
of time to elapse between tests in or
der that the fishes may return to re-
ceptive state. In the approach of a
motor boat the sound that first reaches
the fish must be far too faint TO call
forth any response and this sound
grows so gradually in intensity and
with such rapid reiteration that the
fish probably acquires the state of non
reaction to sound by the time the slim
illus has grown to such an intensity as
would have been effective had a single
shock been delivered at once to the
fish. The gradual approach of the boat,
then, does away with the element of
contrast between silence and loud
noise, and the result is just the reverse
of that of summation, so often seen I'm
the application Of minimal stimuli to
sense organs; theHsh fails to respond.
'fFrom these observations it seems
quite clear that sihsie. loud noises gth
Grated in the airlpnter water to q
small extent and i'm sufficient volume
to disturb momentarily fishes that are
in the immediate vicinity. But even
this limited disturbance does not
seem to be produced by the ordinary
motor boat which, partly because of
the faintness of its sound under water
and partly because of the gradual in
crease and decrease of the sound in in
tensity as the boat approaches and re-
cedes is relatively inert so far as many
fish are concerned.
| The problem of the relation of fishes
to sounds is almost always taken up
from the standpoint of negative reac-
ton, i'm that it is assumed that noise
drives fishes away. II must be rcmem-
bered. however. that there are fishes,
| like the drumfish, and especially the
Isqueteague. that produce noises which
are without much doubt concerned
with bringing the sexes together i'm the
breeding season and that these noises,
therefore, are not repellent but serve
to attract. Cases of this Kind show
that it is possible that even artificial
noises, if appropriate i'm character,
might attract fishes, for sound, even
when disagreoable to the human ear,
Is not of necessity always disturbing
to fishes and might even serve as a
lure"