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maturity retaining a brighter silvery colour, and being more similar to the female
fish. Food appears to have much less influence on the coloration of the outer-parts
than on that of the flesh ; the more variegated specimens being frequently out of
condition, whilst well-fed individuals with pinkish flesh are of a more uniform,
though bright, coloration. . . . The water has a marked influence on the colours ;
trout with intense ocellated spots are generally found in clear rapid rivers, and in
small open Alpine pools ; in the large lakes with pebbly bottom the fish are bright
silvery, and the ocellated spots are mixed with or replaced by X-shaped black spots ;
in pools or parts of lakes with muddy or peaty bottom, the trout are of a darker
colour generally ; and when enclosed in caves or holes, they may assume an almost
uniform blackish coloration." A change of colour also takes place in the migratory
species with the renovation of the scales, which occurs during their residence
in the sea, the newly-grown portion of the silvery scales concealing the spots ; and
this change of coloration varies greatly according to the habitat of the individuals
of some of the species. Variations of size are also common, these being for the
most part dependent upon the abundance or otherwise of the food, and the extent
of the area in which the fish dwell; but differences in this respect also occur
among the fish hatched from the same batch of spawn, and living under the same
conditions. The variations in the form and proportions of the body, and more
especially in the head and jaws, according to age, sex, and season, are likewise very
important, but cannot be noticed fully.

The true salmon (S. solar), together with the kindred species
and the trouts, belongs to a group of the genus characterised by the
presence of teeth on the whole length of the vomer during at least some period of
life. In the case of such a well-known fish and also one which is generally
pretty easy to distinguish from its congeners it will be unnecessary to give a
description. Dr. Glinther gives, however, certain characters by which this fish
may always be identified, and among these the following may be noticed. The
scales on the tail are of relatively large size, and each transverse series running
from behind the fatty fin towards the lateral line contains only eleven, or occa-
sionally twelve, whereas in the trouts there are from thirteen to fifteen. Secondly,
the main part or body of the vomer carries a single series of small teeth, which,
with advancing age, gradually disappear from behind forwards, so that half-grown
and adult individuals have but a few remaining. Having a circumpolar distribution,
the salmon ranges southwards in America to 41 north latitude, and in the Old
World to 43, being unknown in any of the rivers flowing into the Mediterranean.
Salmon will grow to a length of between 4 and 5 feet, and commonly reach as
much as 40 Ibs. Much heavier fish are, however, occasionally captured. Among
these may be mentioned a salmon of 60 Ibs. from the Severn in 1889; one from the



496 TUBE-B LADDERED GROUP.

Tay of 62 Ibs. in 1891 ; a third of 63 Ibs. from the Esk in 1890; another of 68 Ibs.
from the Tay in 1893 ; and a fifth from the same river taken in 1870, which
weighed a fraction under 70 Ibs. There is an earlier record of a British salmon
of 83 Ibs. weight, while a Russian is stated to have scaled upwards of 93 Ibs.

For the following brief sketch of the life-history of the salmon, we are
indebted to a paper by Mr. G. Hooper, from which the following extracts, with
some verbal alterations, are taken. After mentioning the well-known periodical
migration of salmon, the writer observes that the eggs are deposited by the female
" some time during the winter months, in beds of gravel over which a rapid stream
flows, principally in the upper reaches of the river, where the water is more
aerated and free from pollutions of any sort since clay, earth, or any extraneous
substance would choke and destroy the embryo fish. Indeed, from the time
of entering the river, the object of the fish seems to be to arrive at its source.
Until they have spawned they never descend, but, resting at times in favourite
pools, continually struggle upwards. Only the late fish spawn in the lower
waters. To such as have only seen the salmon in prime condition, the appearance
of the fish when on the eve of spawning would come as a surprise. The female
is then dark in colour, almost black, and her shape sadly altered for the worse
from that which she presented when in condition. As for the male, he is about
as hideous as can well be imagined, his general colour being a dirty red, blotched
with orange and dark spots. His jaws are elongated, and the lower one furnished
with a huge beak, as thick, and nearly as long as a man's middle finger; while his
teeth are sharp and numerous, and his head, from the shrinking of the shoulders,
appears disproportionally large. His skin also is slimy and disagreeable to
handle, and, in fact, scarcely a more repulsive creature in appearance exists.
Arrived on the spawning-ground the female, then called a baggit, alone proceeds
to form the nest, or ' redd ' as it is termed. This she effects by a sort of wriggling
motion of the lower part of her body working on the loose gravel. Many authors
state that this is effected by the action of the tail, but I think the convex
formation of the body at that period would prevent the tail touching the gravel,
unless the fish stood at an angle of 45, in which case the stream would carry
her down. The redd, a deep trench, being formed, the female proceeds, attended
by the male fish frequently by two kippers, as they are then called to deposit
her eggs. This she does, not all at once, but in small quantities at intervals,
frequently returning to the redd for the purpose. The eggs are at once fecundated
by the milt of the kipper ; this process going on for two or three days, the fish
sinking down occasionally into the pool below to rest and recover their strengtl
The effect of the fertilisation of the ova is to add greatly to their specific gravity
the eggs sink, and are at once covered with gravel by a similar motion on tht
part of the baggit to that used in the formation of the redd. Here, the proces
being completed, the eggs remain during a period of from one hundred and twenty
to one hundred and forty days, according to the temperature of the water. At
the expiration of that time, the little fish come into existence, and, after a few days
wriggle out of their gravelly, bed and seek refuge under an adjacent rock 01
stone, where they remain in safety for some twelve or fourteen days longer.
The appearance of the young fish at that time gives little promise of the beautiful




A SALMON LEAP.



SALMON TRIBE.



497



form to which they subsequently attain. They are indeed shapeless little
monsters, more like tadpoles than fish, each furnished with a little bag of
nutriment forming a portion of the abdomen. On this, for two or three weeks,
they subsist, until it is absorbed, when they take the form of fishes. They arc then
about 1 inch in length, and are known as salmon-fry or samlets. A portion of
the eggs are washed down the stream during the process of spawning, and become
the prey of trout and other fish which attend the redds for the purpose of feeding
on them. In this they do no harm whatever, for these eggs, being uncovered and
unfecundated, could never arrive at maturity. The kippers, when not actually
engaged in the spawning process, swim rapidly about the redd, fighting fiercely
with one another. The use of the beak appears then to come into operation.
Many authors erroneously describe this beak either as a weapon of offence, or as
a sort of pickaxe used in digging out the redd ; but it seems to me that nature
has provided this singular excrescence as a protection and safeguard against the
savage attacks made on each other. So large is its size, and so closely does it fit
into the hole or socket formed in the upper jaw, that it would appear almost
impossible for the fish even to open his mouth ; but he does so, to some extent at
least, and with its cat-like teeth inflicts deep, and sometimes dangerous wounds
on his antagonists. As to its alleged use as a digging implement, the substance
of the beak is cartilaginous, not horny, and by no means hard ; it would be worn
down in the process of digging in ten minutes, and, moreover, the female alone
prepares the redd. After leaving the stone or rock under which it has sought
protection, the young fish grows very rapidly, as is natural in one destined to
attain such huge dimensions as the salmon. In the course of a month or six
weeks the fry have attained to the length of 4 inches, and are then called ' parr ' ;
when they bear conspicuously on their bodies transverse marks or bars, which
are common to the young of every member of the salmon family. Unfortunately,
there is another little fish, a humble relation of the lordly salmon, also barred, very
similar in appearance, which too is called a parr, and the identity in name and
similarity in appearance has occasioned great confusion and controversy, especially
as they are inhabitants of the same waters, and affect to some extent each other's
company. The time of their remaining in the parr stage is also a subject of
dispute ; and while some say two, three, or sometimes four years, my opinion is
that they remain one year only. In the second April of their existence a change
in the appearance of the parr occurs, which assumes the silvery scales of the adult
fish, wearing his new apparel over his old barred coat. He is now called a ' smolt,'
and perhaps, with a wish to exhibit himself in his new and beautiful apparel,
evinces a daily increasing restlessness and desire to quit his home. With the
first floods in May myriads of these lovely little fishes start on their downward
journey toward the sea. It is a beautiful sight to watch their movements when
descending ; and for many days the river teems with them, not a square foot of
water being without one when the stream is at all rapid. As fry the smolts were
exposed to many dangers, but they were nothing to those which beset them as
parrs on their journey towards the sea. Their enemies are legion. Trout and
pike devour them; gull swoop down and swallow them wholesale. Herons,
standing mid-leg deep in the water, pick them out as they pass ; and even their

VOL. V. 32



498 TUBE-BLADDERED GROUP.

own kindred devour them without scruple. Unluckily, too, for them, a certain
number of great, hungry kelts (as the fish are called after spawning), having
recovered to a great extent their condition, accompany them on their seaward
journey, and prey upon their young companions as they travel; and I believe
that a hungry kelt will devour upwards of forty or fifty smolts in a day. Arrived
at the sea, the little fish are met by a fresh array of enemies. The army of gulls
is always with them, and these are reinforced by cormorants, divers, and other
sea-birds, besides which shoals of ravenous fish await their arrival, and assist in
thinning their ranks. It is wonderful that any should escape, and, but for the
extraordinary fecundity of the salmon, they would speedily be annihilated; but
such is their prolific nature that a remnant always survives to return to the
spawning-beds and keep up the supply. Buckland calculated that the number of
eggs laid by a salmon was about one thousand to the pound weight, a fish of
15 Ibs. therefore producing fifteen thousand eggs. The food of the smolt during
his sojourn in the sea is abundant, consisting chiefly of sand-eels, molluscs, and
marine insects. The smolts increase accordingly very rapidly in size, and in three
or four months the fish that came down 5 or 6 ounces in weight returns to the
river from whence he came, a grilse of from 4 to 6 Ibs. ; the grilse being the fifth
stage of the salmon's existence. Unless accidentally prevented the grilse always
returns to the river from whence it came, and after spending the autumn and
winter at home, and providing for the continuance of the family by spawning, as
already described, returns as a kelt to the sea in the following year, reappearing
the next as a salmon of at least 10 or 12 Ibs. weight. It should be added, that,
after spawning, the fish speedily recover their colour, and to a great extent their
condition ; the baggit at once losing her dark complexion, and the kipper discarding
his hideous livery, his great beak being rapidly absorbed, his sides becoming
silvery, and his back assuming a dark bluish tinge."

With reference to the statement in this account that salmon always return to
the river of their birth, it may be observed that although this is generally the
case, the circumstance that salmon occasionally make their appearance at the mouth
of the Thames and other rivers which they have ceased to inhabit, shows that
there are exceptions to the rule. The obstacles that salmon will surmount in
their ascent of rivers during the return frcm the sea are too well-known to require
notice; but it is probable that the height to which they can leap has been
exaggerated. The period of spawning varies with the country, taking place in
the south of Sweden and North Germany at the latter part of October or early
in November; while in Denmark it may be deferred till February or the
beginning of March ; November and December being the usual spawning-months
in Scotland.

Trout ^ n s P^ e ^ *heir diversity of habitat, and likewise of coloration

and structure, Day is of opinion that the migratory sea-trout, or
salmon-trout (8. trutta}, and the stationary river-trout (S. fario), as well as the
various forms from the British lakes, are nothing more than varieties of a single
variable race ; and it must be confessed that no one has hitherto been able to define
all the nominal British species with anything like definiteness. Still, however, in
the modern sense of the words there is no possibility of drawing a hard-and-fast



SALMON TRIBE.



499



line between a species and a variety; and the question is accordingly of no very
great importance one way or another. Some of the characters distinguishing the
salmon from the trout have been already indicated on p. 494; and it will suffice to
note very shortly some of the reasons given by Day for regarding all the British
trout as referable to a single species. It is well known that sea-trout as
represented not only by the typical form, but likewise by the so-called sewen
(S. cambncus) of the Welsh rivers-are silvery in colour, with black spots during
their sojourn m the sea; when, however, they enter the rivers for the purpose of
spawning, an orange margin appears on the upper and lower edges of the caudal,





MAY-TROUT AND HUCHO (^ 5 liat. size).

and likewise on the fatty, fin ; while spots of the same colour show themselves on
the body. On the other hand, the nonmigratory forms may be arranged under
two types of coloration, some loch-trout (which may have been originally migratory,
but are now landlocked) being mainly silvery during the smolt-stage. and subse-
quently golden and spotted ; while the estuarine, lake, and river-trout are all
golden, with purplish reflections, and more or less fully marked with black and
vermilion spots. It appears, indeed, that a long residence in fresh water generally
leads to the disappearance of the silvery sheen characteristic of the salmonoids
while in the sea (and which is probably their primitive type of coloration), and to
the promotion of colour. As a partially transitional type between sea-trout and



5 oo TUBE-BLADDERED GROUP.

river-trout may be taken the Lochleven trout, which is somewhat silvery during
the smolt-stage, with the spots generally black, and no orange border to the fatty
fin, but at a later stage assumes the general coloration of the river-trout, although
lacking the white black-based front margin to the dorsal, anal, and pelvic fins
characteristic of the latter. Silvery trout do, however, occasionally occur in fresh
waters, where there is no possibility of their having migrated from the sea. In
concluding his observations concerning the coloration of trout, Day writes that
" reasons have been shown for admitting that sea-trout might breed in fresh waters
without descending to the sea. That they can be traced step by step, and link by
link, into the brook-trout, and vice-versa ; that the Lochleven trout, which normally
possesses a smolt- or grilse - stage, passes into the brook-trout; and also that
breeding any of these two forms together sets up no unusual phenomena," Later
on, he observes that some of the chief distinctions between the sea- and fresh-water
forms of trout consist in the comparatively more complete system of dentition in
the fresh-water races, their generally longer head, blunter muzzle, and stronger
upper-jaw, irrespective of the smaller number of blind appendages to the intestine.
The dentition is, however, excessively variable ; and specimens with the coloration
and form of the river-trout taken in estuaries, or even in the sea, usually have the
small number of vomerine teeth characteristic of the migratory forms ; while, on
the other hand, fresh-water examples with the coloration of the migratory type,
may have a dentition of the nonmigratory type. " It has been asserted that
brook-trout invariably have a double row of teeth along the body of the vomer,
and some authors have gone so far as to assert that these teeth are not deciduous.
Doubtless it is not uncommon to find trout up to 2 Ibs. weight, or even more, with
all the vomerine teeth thus remaining intact when a double row is present ; but
it is by no means rare to see only one irregularly-placed row, while in very large
specimens these teeth (unless they have entirely disappeared) are always in a
single row, and the vomer may be found toothless, or with only one or two teeth
at the hinder edge of the head. Equally incorrect is the statement that the teeth
disappear differently in different forms, for in all they first assume a single row,
and then fall out, first commencing from behind. But in the rapidly growing
sea-trout the vomerine teeth are shed sooner than in the brook-trout." The limits
of our space preclude our entering further into the consideration of this interesting
subject. The ordinary sea-trout, which is essentially a North-European fish, much
more common in Scotland than in England, and grows to a length of 3 feet, is
depicted in the lower figure of the illustration on p. 493 ; while, as an example of
a spotted form, we take a variety of the Continental lake-trout (8. ku-iiKfri*\
shown in the upper figure of the illustration on p. 499. Known on the Continent
as the maiforelle (May-trout), this fish has the sides of the body marked with
irregular angular or X-shaped black spots, between which are red spots, tlu-sr
spots becoming less numerous beneath the lateral line, while the under surface
may be tinged with red. On the gill-cover the spots are larger and more rounded.
In the typical variety of this trout, from the Lake of Constance, the spots do not
extend below the lateral line ; this form being known as the scJnrcl^nrUfl. The
migrations of the sea- trout are very similar to those of the salmon; in Sutherland
the great run of these fish to the sea taking place in June, while they reasocinl



SALMON TRIBE.



5 01



the rivers in autumn to spawn. Jardine writes that " in approaching the entrance
of rivers, or in seeking out, as it were, some one they preferred, shoals of this fish
may be seen coasting the bays and headlands, leaping and sporting in great
numbers, from 1 to 3 or 4 Ibs. in weight ; and in some of the smaller bays the
shoals can be traced several times circling it, and apparently feeding." On the
other hand, the Continental May-trout spends the colder months in the deepest
waters of the mountain-lakes, only coming to the surface in May. During the
summer these trout may be seen swimming round the shoals of small fishes on
which they prey until they get them well together, when they make a sudden rush
among them.

Much the same difference of opinion as obtains with regard
to the number of species of trout exists in the case of charr,



Charr.




GRAYLING AND CHARR (J Hat. size).

Dr. Giinther recognising five British lacustrine species, which he regards as distinct
from 8. umbla of the Swiss lakes'; while Day includes the whole of these under
the latter, which is also taken to embrace the sibling (8. salvdinus) of the
mountain-lakes of Bavaria and Austria, as well as the migratory northern charr
(8. alpinus), ranging from Lapland and Scandinavia to Iceland and the northern
parts of Scotland. All charr differ from salmon and trout in having the teeth at
all ages confined to the head of the vomer, instead of being distributed over its
whole length; and all the forms mentioned above, which have a very uniform



5 o2 TUBE-BLADDERED GROUP.

type of coloration, agree in having median teeth on the hyoid bone. Without
committing ourselves definitely, we confess that we are inclined to agree with
Day as to the specific identity of the whole of them. To illustrate the group, we
have the sibling depicted in the lower figure of the illustration on p. 501.
In the spawning-season the upper-parts of this fish are brownish green, and the
sides lighter ; the under surface passing through all shades of orange to vermilion,
from the throat to the pelvic fins, where the colour attains its greatest intensity.
The sides are ornamented with rounded spots varying from white to red in colour ;
the dorsal fin has dark markings, and the pectoral and pelvic fins are brilliant red.
This form commonly grows to a length of 8 or 9 inches, but the northern charr
attains much larger dimensions. Day writes that "the colours of the British
charr do not vary to so great an extent as in the trout, owing to their residing in
deeper waters, and usually merely ascending towards the surface at night-time to
feed, while other changes in tint are consequent upon the breeding-season. In
the Lakes of Cumberland, Westmoreland, and Lancashire this fish in its ordinary
state is the case-charr of Pennant ; when exhibiting the bright crimson belly
which it assumes before spawning, it is called the red charr; when out of season,
the spawn having been shed, it is distinguished by the name of the gilt charr. . . .
Charr are a more delicate and apparently shorter-lived fish than trout, requiring
deeper and stiller pieces of water, and a colder temperature ; they have even been
recorded as residing in lochs where the sun never reaches the surface of the water.
They are readily destroyed by poisonous substances ; while attempts to introduce
them to fresh localities have not been so uniformly successful as with the trout."

The North American charr (S. fontinalis), whicli has been successfully intro-
duced into British waters, together with the hucho (S. hucho) of the Danube, differ
from the foregoing in the absence of median teeth on the hyoid bone ; the latter
fish being shown in the lower figure of the illustration on p. 499. The general
colour of the American charr is greenish, lighter above than beneath, beautifully
shot with purple and gold, ornamented with numerous dark spots above, and fewer
below the lateral line, many of which in front of the dorsal fin coalesce into
streaks, and also with red spots above the aforesaid line. Most of the fins have,
dark markings ; and in the breeding-season the male assumes a black line along
the under surface. These fish usually range in size from 2 to 3 Ibs., although
they may be larger. The hucho, on the other hand, which is readily characterised
by its elongated, slender, and almost cylindrical form, attains dimensions equal to
those of the salmon.

Many-Rayed A group of migratory salmonoids (Onchorhynchus) inhabiting the

Salmon. North American and Asiatic rivers flowing into the Pacific differ
from the typical genus in having more than fourteen rays in the anal fin ; while
their kelts are remarkable for the degree to which the jaws are hooked, and the
humping of the back. An early writer in describing the hordes in which these
salmon annually visit Kamschatka, states that they " come from the sea in such
numbers that they stop the course of the rivers, and cause them to overflow the
banks; and when the waters fall there remains a surprising quantity of dead fish
upon the shore, which produces an incomparable stink ; and at this time the bears
and dogs catch more fish with their paws than people do at other places with their



Online LibraryRichard LydekkerThe new natural history (Volume 5) → online text (page 53 of 62)