54 
FOREST AND STREAM. 
[July 8, 1911. 
any seven-year-old maiden fish, which would 
probably weigh about 50 pounds. Naturally the 
numbers of such fish would be limited, and they 
might escape capture. 
I know it is difficult to upset old ideas and 
prejudices, but,any one who seriously investi¬ 
gates the subject is forced to the conclusion 
that at any rate in large rivers like the Tay or 
the Wye, the greater majority of the fish, even 
those of 30 or 40 pounds, are maiden fish re¬ 
entering the river to spawn for the first time. 
If any one is sceptical about the theory of scale 
markings, I can only refer him to the results of 
the valuable experiments carried out on the Tay 
under Mr. Malloch’s supervision. Of the 6,500 
smolts which were marked with fine silver wire 
during the migration in 1905, not one was re¬ 
caught that year, but in succeeding years we get 
the following remarkable results: 
1906— Forty grilse were caught with the wire 
marks, varying from 2 15-16 to 10P2 pounds in 
weight. 
1907— Fifty-seven fish were caught with the 
marks, varying in weight from 7 to 27 pounds. 
1908— Four fish were caught with the marks, 
varying in weight from 13 to 35 pounds. 
Scales have been taken from these fish, and 
the estimated age of the fish as shown by the 
rings on the scales, according to Mr. John¬ 
ston’s theory, is in absolute agreement with the 
actual age of the fish as shown by the wire 
marks. We ljave here a clear case of theory 
being confirmed by practice, and I think even 
the most hardened sceptic must admit that Mr. 
Johnston’s scale theory has been proved up to 
the hilt, at any rate as far as maiden fish are 
concerned. 
A salmon acquires most of its scales shortly 
after birth, and generally speaking, obtains no 
new ones in the latter period of its life, except 
perhaps to replace lost scales. The scales in¬ 
crease in size as the fish grows by the addition 
of rings or ridges around the circumference of 
each scale, in somewhat the same manner as 
the growth of a tree. There is, however, this 
difference, that a considerable number of rings 
are added in each year. In the winter when 
there is a scarcity of food, the small parr ceases 
to feed, and there is a cessation in growth. We 
consequently find on each scale around the 
center of growth, a number of concentric rings, 
comparatively wide apart, representing the feed¬ 
ing during the first summer of its life, and sur¬ 
rounding these a few lines closer together which 
indicate the slackened growth as winter ap¬ 
proaches. Around this inner core is a further 
series of summer lines, surrounded by a second 
winter band. In the third year of the fish's life, 
we generally find in addition, two to three, or it 
may be more, rings representing the early 
feeding in the river or in water just above the 
tide reach, before its departure to the richer 
feeding of the sea as a smolt a few inches long. 
Although in British rivers it would appear that 
the majority of the parr migrate when a little 
over two years in age, some may delay their 
departure until three years old, and possibly 
longer, and a certain number may migrate when 
only a year old. Immature sea trout may hang 
about the estuaries for a long time, but it would 
appear that salmon smolts when once they 
enter the brackish water, make a prompt pas¬ 
sage through the estuarial waters to the sea. 
When the smolt enters the rich feeding grounds 
of the sea, rapid growth commences, and is 
shown by the addition of lines or ridges of an 
altogether different character far apart and 
strongly marked. In the sea, however, during the 
winter there is also a diminution in rate of growth, 
if not an absolute cessation of feeding. This 
may be due to lessened food supplies or to some 
form of hibernation, or possibly to satiation and 
SCALE OF ADULT SALMON. 
SCALE FROM THE MEDIAN LINE. 
the consequent- necessity of resting from feed¬ 
ing. It may be due to the spawning instinct de¬ 
veloping itseif, for I am inclined to think that 
when the mature fish once approaches a river 
with the intention of spawning, it ceases to feed. 
In this connection I should draw attention to 
a rather remarkable note in Willis Bund’s in¬ 
teresting book, “Sa’mon Problems,” on page 208: 
“The Usk salmon in the Brighton Aquarium 
died in the summer of 1878. It was placed there 
as a smolt on April 5, 1873, and in the follow¬ 
ing month was transferred to salt water, in which 
it remained for upward of five years, feeding 
freely on shrimps, etc., during a portion of the 
year, but abstaining from food between August 
and February.” 
The cessation or diminution of feeding in the 
sea is generally marked by a winter band or 
series of closer lines or ridges, and in the case 
of grilse scales, surrounding these we find a fur¬ 
ther series of wide rings denoting the portion 
of the second summer spent in the sea. I can¬ 
not emphasize the fact too strongly that the 
scales of all grilse show more or less clearly de¬ 
fined this dark band representing one winter 
spent in the sea, proving that no grilse returns 
to the river in the same year in which it 
migrates. The truth of this theory was 
more than confirmed by the results of the 
Tay marking experiments, to which I have 
already alluded. There does not seem to be 
any possible room for doubt that this winter 
band is formed in the sea, and I have lately re¬ 
ceived further confirmation of this from some 
scales sent me by Flerr Knut Dahl, taken from 
a small salmon about 10^2 inches long, caught in 
the open sea off the Norwegian coast. 
If we find on larger fish not only one winter 
band, but two or three, and occasionally four 
such bands, each surrounding a full series of 
summer rings, I think it is a logical conclusion 
that all such winter bands are formed in the 
sea, and not in the river, and therefore that Mr. 
Johnston’s theory is correct, and that a large 
number of fish running up to forty pounds and 
more in weight are maiden fish entering the 
river for the first time. This is more evident 
when we compare the spawning mark with the 
winter band or check. 
A salmon may enter a river in January or even 
earlier, but will not spawn until the following 
October, November or December,-nor return to 
the sea until some months later. In other words 
it may spend twelve months or more in fresh 
water, practically fasting the whole of that time. 
The fish diminishes in hulk every day after en¬ 
tering the river, and there is a further loss in 
weight and bulk in the operation of spawning. 
The skin has to accommodate itself to the les¬ 
sened bulk of the fish, but the scales cannot 
shrink, and they become disintegrated and frayed 
and worn away, especially at the sides. Conse¬ 
quently when the fish re-enters the sea as a 
kelt, the scales are altogether different in shape 
from those of a fresh fish, and are irregular in 
outline with rough and ragged edges. 
On returning to the sea the fish begins to 
feed ravenously and, therefore, in the case of 
a fish returning to the river for the second time 
to spawn we find broad, well marked ridges, de¬ 
noting rapid feeding, surrounding the old kelt 
scales, and between them is a scar or “spawning 
mark” affording evidence that the fish in ques¬ 
tion has previously entered the river and 
spawned. That is the theory, but again we have 
confirmation in practice, for scales have been 
taken from marked kelts, and some of these 
have been subsequently recaptured as clean fish, 
and their scales all show an undoubted “spawn¬ 
ing mark.” 
In this connection it should not be forgotten 
that the Pacific salmon, which have 400 miles or 
more to run up the rivers in order to reach the 
spawning grounds, are ah said to die after spawn¬ 
ing. Notwithstanding this, these salmon enter the 
river in all sizes from a few pounds up to eighty 
pounds and more. All these fish must be maiden 
fish, thus adding confirmation, if it were needed, 
to Mr. Johnston’s theory. It is possible that if 
the rivers of North America were shorter some 
(Continued on page 74.) 
