The times. [volume] (Washington [D.C.]) 1897-1901, 1900-12-16
TAGGING ocean FISHES
Methods Of Identifying Members
of the Cod Tribe.
Operations OF the Government Com
mission 10 Gathe. Information
Concerning the Character of the
Particular Branch of the Pixcato-
rinl FnmiIy-Dccp-Sca Denixcns.

metal tags to marine fishes, and then lie;
them loose in the ocean with the idea O.
identifying them as individuals in cast
they happen to be caught at 4 future time
but this is what the United States Fist
Commission is doing just now with cod
fifteen hundred of which have been dcl,
tagged and released this year. No twt
tags are alike. the mark nss en- then, be.
ing stamped in series Of letters an6
numbers, record of which is kept in q
book in such 4 manner that, il tagged
Goldfish turns up, moments reference
to the memoranda will furnish the history
OF that particular specimen, with date OF
liberation. weight. and SO forth. For ex-
ample, a cod wearing tag with the
raised inscription IS 100 has complete
Identification card. SO that she cannot be
mixed UP with any other fsn entered in
the Commissions ledger.
Only brood fish"-that is, spawning fe-
males-are tagged. They are bought from
fishermen. stripped of their eggs at Wood
Holl, Mass, and liberated in the waters
OF Vineyard Sound. after having the tags
attached to them. The tag is a small
piece of copper, securely fastened by a
wire passed through fin near its juno
tion with the body. 1t does not matter
which fin is chosen. though back or tell
nm is best. The tag is very light and its
attachment in the manner described does
no harm whatever to the animal. During
the last few months the Fish Commission
has distributed a circular all along the
coast of New England, requesting that
whenever 4 cod with a tag comes into the
hands OF fisherman or other person. he
Shall remove the piece Of metal and send
II to the Commission station at Woods
Holl, together with brief statement as
to the date on which the fish was caught,
where ii was captured, its weight before
dressed, its length and the condition CT its
roe.
The object of the tagging is to ascertain
the rate at which cod grows, the fire.
quency OF its spawning, and the extent
OF Its travels in the ocean. knowledge of
this kind has an obvious bearing upon
hshcuitural problems, and there is every
reason TO believe that the future of the
cod fishery OF the New England coast
must depend mainly upon artificial hatch
ing. The Matching OF cod eggs and the
planting of the fry in those waters has
been carried on for several years. and al
ready the fishery shows a notable i'm
provement. apparently due to this work
During the present year, the work coming
10 an end April ], there were painted in
New England waters $50, 600 600 Goldfish.
This year the Fish Commission is going
to bag many thousand of young salmon,
artiflciaily Matched for the rivers of the
Pacific Coast. Very email tags will be
used. the fishes being ''fngerlings," about
three inches long. 1t is expected that in
this way will be ascertained the age at
which the salmon come from the sea to
spawn: also their rate of growth and the
percentage Of the fry that attain MATURE
~. The work will be carried on in the
basins OF the Columbia and Sacramento
Some years ago a similar experiment
was made at the Fish Commission station
On the Clackamas River. which is tribu-
tary Of the Columbia: but. instead Of tag
Bing the young fishes the soft dorsal fins
we're shaved of Of them with a razor be-
Tore they were released. When they came
back to spawn. three years later they av-
eraged twenty pounds In weight.
From this experiment one or two very
interesting conclusions were drawn. III all |
OF the artifcially Matched fry had survived |
and been captured. It is obvious that LOCO !!
OF them would have contributed .0Oa 3
pounds of food fish for market AS 4 mat.
ter OF fact, only one out Of ten of them
returned, and was taken. the result being
z,co0 pounds of fish for every 1eGe young
ones liberated
The Fish Commission is also at presrn.
engaged upon a very interesting investi-
cation into the nature and habits of deem.
yea fishes.
1t was comparatively but a short time
ago that the singularity OF some spec1-
mems found in the North Atlantic led TO
the opinion that their peculiarities were
o~lDs TO their inhabiting great depths OF
the ocean. These fishes agreed in the
character OF their connective tissue
which was so extremely weak as to Weld
10 and to break under the slightest press-
ure, SO that the greatest difficulty was
experienced in preserving their bodies in
continuity. Another singular circum-
stance was that some of the examples
were picked up floating on the surface
OF the water. having met their death
whilst engaged in Swallowing OF digest!ng
other fishes not much smaller in size
IL not actually larger. than themselves
The TACT OF their looseness of tissue
was accounted for by the fact that II
.hese fishes really inhabited the great
iepths supposed, their removal from tho
'normous pressure Under which they lived ,
would be accomplished by such an ey-
pansion OF gasses within their tissues az f;
o rupture them and to cause separation
,f the parts which had been kept To-
sether by the pressure
Inc second circumstance was explained ,
hus: raptorial fish organized 10 live /,
Il depth OF between 500 and 500 faith
ms. seizes another usually inhabitiny
lepfh OF between 400 and 500 fa:bomq
a It's struggle toescape, the fish seized
'elng nearly as large or strong rs the ,
ttacking fish. carries the latter out OF
Is depth into higher stratum. where the =,
diminished pressure causes such an ex
ansion of gases as to make the DESTROYER .
nm It's victim rise with increasing rap !,
iity toward the surface which both
each dead or In a dying condition. Speci
lens in this state have often been found
nd as these represent but a very small
OF the actual number of cases ,
is inferred that these must be very pu,
ferrous. |
The fact that these fishes have been
,und at reS distant parts of the ocean
Is iurther inferred that they are not y
United in their range, and that conse- Z
uently the physical conditions Of The I
epths OF the ocean must be the same. or r
early the same. over the whole globe
he deep-sea fishes already found are NOT u
peculiar order. but are chiefly modi-
I'd forms of surface types.
The most striking characteristic found
many deep-sea fishes is in relation to I
ie tremendous pressure under which u ey
We. Their osseous and muscular sys- O
ms are as compared with the same PARTS O
surface fishes. very feebly deveIoped. b
he bones have a ibrous fissured. and I;
IVernous texture; they are light with Z;
,arcely any calcareous matter so that Z,
re point Of needle will readily pene- :,
ate them without breaking. The bones. r
pecially the vertebrae, appear to be >,
Try loosely connected with one another. =,
ID IL requires the most careful handling | y,