The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1904-06-28

States Commission of Fish and Fish
cries began the experiment Of tagging
adult cod and then releasing them in
order to secure certain data when these
liberated fish were caught. The scheme
has been fairly successful, and the
information obtained has proved of
considerable value to ichthyologists
during the short time it has been in
operation.
The cod which were thus treated had
been caught in October and November
of each year on Nantucket Shoals, and
station in the wells of fishing vessels.
The fish weighed from two and two
third to twenty pounds. and were what
the fishermen call the Shore cod" as
The average weight of those released
was five pounds.
The fish were caught with hand lines,
and only those in which the hook
wounds were trivial We're retained.
! Immediately on arriving at the sta
ton they were Transcend to large
floating cars, in which they were held
pending the ripening Of their eggs. The
egg taking season is from the middle
of November to the last of January or
first Of February, and the maturing of
the eggs of individual fish often ex-
tends over a period of several weeks,
during which time the fish are handled
two or three times a week. AS soon
as fish has been finally stripped it
is set at liberty, either in Vineyard
Sound or Buzzard's Bay.
Owing to the captivity and to the
rather rough handling to which the
brood cod are necessarily subjected in
taking their spawn and milt, in addi-
ton to the loss of vitality incident TO
the spawning process, they became
much emaciated, and some of them
succum, Notwithstanding CLAIMS and
I fish are fed to them.
The first tags used were of pure
sheet tin, but these proved unsatis-
factory as the salt water corroded
them. Later they were cut from sheet
copper, as this metal is cheap and
withstands the action Of salt water
for long time. They were from five
sixteenths to three-quarters of an inch
long, and one-quarter of an inch wide.
A small hole was punched in one end,
through which q fine copper wire was
passed, attaching the tag to the fish.
The places of attachment were the
bases of the three dorsal fins. the
bases of the anal fins, and the upper
and lower caudal 1obes. Most of the
tags were fastened to the upper part
of the caudal fin, near it's junction !
with the peduncle, where the rays are |
toughest and the tags are least liable |
to be torn out. To facilitate the pass
age of the wire through the fin an |
aneurism needle was used. The fish !
were then towed into the sound or bay
in live cars and turned loose. The |
record kept for each fish comprised !
the following items: Tag number, posi-
ton of the tag, date when released,
where released, the weight, length, !
sex and spawning condition whether |
spent or immature).
In order to acquaint fishermen and
fish dealers with the purposes of the :.
tagging, and to encourage the preserv-
alton and return of the tags, a circu-
lar was printed and distributed in the
fishing towns in November, 1897. The
circular contained a cut of a cod
showing the position of the tags, and
asked that any person coming into pos
session of a cod having such a tag
the latter by mail to the Unit
ed States Fish Commission, Washing
ton, or to the United States Fish Com
mission Station, Woods Hole, together
with the following information con-
corning the fish: The date when
caught. on what grounds taken, weight
before being dressed, total length meas
ured from end of nose to end of tail
sex. and whether milt or eggs were ripe,
large, but not ripe, or immature.
The noyelty-of the scheme excited
unusual interest, and the hearty CO.
operation of the fishermen was secur-
ed, as was shown by the large num-
Der of tags recovered and the filling
Of full data regarding the captured
fish
The number of fish tagged during the
our winters covered by the experiment
vas 4,O19. Up to December 81, 1901. 40
1f these were captured by commercial
fishermen. In addition to the above.
here were number of tagged fish
aiken for which records are unobtain-
tble, the fishermen having lost or mis-
aid the tags or failed TO report the
'aptures. In some cases the cod were
liberated alive when the fishermen dis
covered the tags, without any record
'eing made of the tag numbers. In a
ew instances fishermen have failed to
eport the catching of the tagged cod
through fear that there was some
'enalty attached TO the killing of such
sh. In a number Of instances the tags
ad not been observed for some time
fter the fish were caught. In at least
ne case a tag was overlooked by the